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1
Zakrevska, M. V., and A. M. Tybinka. "Histological characteristics of accessory adrenal glands of rabbits with different types of autonomous tonus." Scientific Messenger of LNU of Veterinary Medicine and Biotechnology 21, no. 93 (April 2, 2019): 125–30. http://dx.doi.org/10.32718/nvlvet9322.
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For the purposes of the adrenal gland’s study, 27 four months old male rabbits (Oryctolagus cuniculus) of Termond White breed were selected. Based on electrocardiography and variation pulsometry results, three types of autonomous tonus were determined in animals: sympathicotonia (ST), normotonia (NT) and parasympathicotonia (PS), which formed the basis for the division of animals into three groups. All rabbits were subjected to euthanasia and histological preparations were made from their adrenal glands. Apart from the main adrenal gland, accessory adrenal gland was detected in five purposes animals, including three ST rabbits, one NT rabbit and one PS rabbit. Also, four accessory adrenal glands were revealed in one ST rabbit simultaneously. In fact, these accessory adrenal glands became the main object of the further morphological research. The obtained historical indicators accessory adrenal glands were compared to the ones from various animal groups (CT with NT and CT with PS), as well as to the indicators of the main adrenal gland in each group. Statistical analysis of the received data was performed only in the group of ST animals. Accessory adrenal gland of ST rabbits is represented by two zones: zona glomerulosa and zona fasciculata, the area of which is 52% and 48% respectively. In PS and NT rabbits, the glands are formed by zona glomerulosa only. Investigating the accessory adrenal gland’s cellular component, it was found that NT rabbits have the largest cell area in zona glomerulosa, while PS rabbits have the smallest one. At the same time, the area of nucleus has the largest values in ST animals and the smallest ones in PS animals likewise. Сomparing zona glomerulosa and zona fasciculata in ST rabbits, it was found that cell size differs significantly, while the area of nucleus is almost identical. The nuclear-cytoplasmic ratio in zona glomerulosa cells is the largest for PS rabbits. The smallest ratio values were detected among the NT rabbits. Obviously, ST rabbits occupy an intermediate position. Unlike the main adrenal gland, the cells of accessory adrenal gland are of a smaller size and а denser location of cells in all groups of animals. The conducted studies allow concluding that the typological features of the autonomous tonus affect the morphology of accessory adrenal gland.
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Crossley, David A. "Animal salivary glands." Journal of Small Animal Practice 41, no. 9 (September 2000): 427. http://dx.doi.org/10.1111/j.1748-5827.2000.tb03238.x.
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Spencer, Thomas E., Andrew M. Kelleher, and Frank F. Bartol. "Development and Function of Uterine Glands in Domestic Animals." Annual Review of Animal Biosciences 7, no. 1 (February 15, 2019): 125–47. http://dx.doi.org/10.1146/annurev-animal-020518-115321.
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All mammalian uteri contain glands that synthesize or transport and secrete substances into the uterine lumen. Uterine gland development, or adenogenesis, is uniquely a postnatal event in sheep and pigs and involves differentiation of glandular epithelium from luminal epithelium, followed by invagination and coiling morphogenesis throughout the stroma. Intrinsic transcription factors and extrinsic factors from the ovary and pituitary as well as the mammary gland (lactocrine) regulate uterine adenogenesis. Recurrent pregnancy loss is observed in the ovine uterine gland knockout sheep, providing unequivocal evidence that glands and their products are essential for fertility. Uterine gland hyperplasia and hypertrophy during pregnancy are controlled by sequential actions of hormones from the ovary and/or pituitary as well as the placenta. Gland-derived histotroph is transported by placental areolae for fetal growth. Increased knowledge of uterine gland biology is expected to improve pregnancy outcomes, as well as the health and productivity of mothers and their offspring.
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Grundmann, O., G. C. Mitchell, and K. H. Limesand. "Sensitivity of Salivary Glands to Radiation: from Animal Models to Therapies." Journal of Dental Research 88, no. 10 (September 25, 2009): 894–903. http://dx.doi.org/10.1177/0022034509343143.
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Radiation therapy for head and neck cancer causes significant secondary side-effects in normal salivary glands, resulting in diminished quality of life for these individuals. Salivary glands are exquisitely sensitive to radiation and display acute and chronic responses to radiotherapy. This review will discuss clinical implications of radiosensitivity in normal salivary glands, compare animal models used to investigate radiation-induced salivary gland damage, address therapeutic advances, and project future directions in the field.
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Dworzyńska, Agnieszka, Katarzyna Paduszyńska, and Lech Pomorski. "Autogenous transplants of adrenal fragments in an animal model." Polish Journal of Surgery 90, no. 4 (June 13, 2018): 23–28. http://dx.doi.org/10.5604/01.3001.0011.8178.
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Introduction Adrenal insufficiency is a typical complication after surgical treatment of adrenal tumors, especially after the removal of both adrenal glands. Human beings are not able to survive without adrenal glands and without proper hormonal substitution. Autotransplantation of a fragment of the adrenal gland may prevent this complication. This can be done by transplanting the entire adrenal glands or its fragment, such as the adrenal cortex cells. In the case of adrenal tumors, the entire adrenal gland can not be transplanted. However, it is possible to transplant cells from the tumor-free part. Succesful adrenal autografts may result in a new treatment of adrenal insufficiency. Materials and Methods: Autograft transplantation was performed on 3 groups of Sprague Dawley rats. In the first group, physiological corticosterone concentrations were determined. These animals were not operated. In the second group, both adrenal glands were removed. Corticosterone concentrations were determined after bilateral adrenalectomy. The third group was divided into two parts. In the first subgroup, bilateral adrenalectomy was performed simultaneosly with adrenal transplant into the omentum. In the second subgroup, right adrenalectomy was performed simultaneosly with and adrenal transplant into the omentum followed a month later by left adrenalectomy. During the experiment, corticosterone concentrations were measured at 4 time points. Results. The statistical difference between corticosterone concentrations in rats after two timed adrenalectomies and rats after bilateral adrenalectomy was statistically different, but these results were far from physiological concentrations.
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Cowan, F. Brian M. "Does the lachrymal salt gland of Malaclemys terrapin have a significant role in osmoregulation?" Canadian Journal of Zoology 68, no. 7 (July 1, 1990): 1520–24. http://dx.doi.org/10.1139/z90-225.
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Several reptiles possess glands capable of secreting fluids with sodium chloride as the major solute. Almost all studies have measured total sodium chloride secreted by these glands, not the concentration of ions. Thus, it has been difficult to evaluate the role of these glands in osmoregulation. The results reported herein on a large sample of Malaclemys terrapin indicate the lachrymal gland is capable of secreting tears with concentrations of sodium chloride exceeding 500 mM. However, the absolute amount of sodium chloride secreted and the generation of "free water" is relatively low, and the response to salt loading is somewhat inconsistent. Furthermore, the lachrymal gland responds consistently to the presence of irritating fumes not apparently related to osmo- or iono-regulation. The ionic and organic contents of the tears resulting from ionic and nonionic stimuli are similar, suggesting that the lachrymal gland is not a dedicated salt gland, but a gland differentiated to serve some other role, as in many other animals. The gland may be adapted to carry out that role with minimal water loss, as expected in euryhaline animal. The evidence indicates that the control of the lachrymal gland in M. terrapin is considerably more complex than that of other known salt glands.
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Wang, Yanli, Sihai Zhao, Liang Bai, Jianglin Fan, and Enqi Liu. "Expression Systems and Species Used for Transgenic Animal Bioreactors." BioMed Research International 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/580463.
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Transgenic animal bioreactors can produce therapeutic proteins with high value for pharmaceutical use. In this paper, we compared different systems capable of producing therapeutic proteins (bacteria, mammalian cells, transgenic plants, and transgenic animals) and found that transgenic animals were potentially ideal bioreactors for the synthesis of pharmaceutical protein complexes. Compared with other transgenic animal expression systems (egg white, blood, urine, seminal plasma, and silkworm cocoon), the mammary glands of transgenic animals have enormous potential. Compared with other mammalian species (pig, goat, sheep, and cow) that are currently being studied as bioreactors, rabbits offer many advantages: high fertility, easy generation of transgenic founders and offspring, insensitivity to prion diseases, relatively high milk production, and no transmission of severe diseases to humans. Noticeably, for a small- or medium-sized facility, the rabbit system is ideal to produce up to 50 kg of protein per year, considering both economical and hygienic aspects; rabbits are attractive candidates for the mammary-gland-specific expression of recombinant proteins. We also reviewed recombinant proteins that have been produced by targeted expression in the mammary glands of rabbits and discussed the limitations of transgenic animal bioreactors.
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González-León, Ezequiel, and Martha Patricia Ramírez-Pinilla. "The mental gland of Bolitoglossa nicefori (Caudata: Plethodontidae)." Amphibia-Reptilia 30, no. 4 (2009): 561–69. http://dx.doi.org/10.1163/156853809789647013.
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AbstractThe mental gland of the plethodontid salamander Bolitoglossa nicefori was examined by macroscopic observation and light microscopy and compared with morphological descriptions of other species of Plethodontidae. The mental gland is an oval shaped pad which develops exclusively in reproductive males. It is composed of 255 to 710 simple glands of merocrine secretion arranged in a dorso-ventral disposition. The outlets of the glands are spindle-shaped or fusiform. Negative stain reaction for AB and PAS is consistent with results of the glandular components of mental glands from other Plethodontidae. Males of this species produce sperm continuously throughout the year: all examined adult males showed conspicuous mental glands. However, an evident and significant increase in the surface area of the mental gland pad, in the density of the glands, and in the number of tubular glands was observed in the males collected during the breeding season. At the histological level, a slight variation was observed among males in the height and diameter of the simple tubular glands, and significant variation was found in the diameter of the secretory granules. This variation may reflect the fact that, although males potentially can mate during all months of the year, females oviposit seasonally. During this defined season, the hypertrophy of the mental gland is the greatest.
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Ness, Anthony, Doris Zeng, Alsu Kuznetsova, Alicia Otero, Chiye Kim, Kelsey Saboraki, Susan Lingle, et al. "Chronic wasting disease prions in mule deer interdigital glands." PLOS ONE 17, no. 10 (October 3, 2022): e0275375. http://dx.doi.org/10.1371/journal.pone.0275375.
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Chronic wasting disease (CWD) is a geographically expanding, fatal neurodegenerative disease in cervids. The disease can be transmitted directly (animal-animal) or indirectly via infectious prions shed into the environment. The precise mechanisms of indirect CWD transmission are unclear but known sources of the infectious prions that contaminate the environment include saliva, urine and feces. We have previously identified PrPC expression in deer interdigital glands, sac-like exocrine structures located between the digits of the hooves. In this study, we assayed for CWD prions within the interdigital glands of CWD infected deer to determine if they could serve as a source of prion shedding and potentially contribute to CWD transmission. Immunohistochemical analysis of interdigital glands from a CWD-infected female mule deer identified disease-associated PrPCWD within clusters of infiltrating leukocytes adjacent to sudoriferous and sebaceous glands, and within the acrosyringeal epidermis of a sudoriferous gland tubule. Proteinase K-resistant PrPCWD material was amplified by serial protein misfolding cyclic amplification (sPMCA) from soil retrieved from between the hoof digits of a clinically affected mule deer. Blinded testing of interdigital glands from 11 mule deer by real-time quake-induced conversion (RT-QuIC) accurately identified CWD-infected animals. The data described suggests that interdigital glands may play a role in the dissemination of CWD prions into the environment, warranting future investigation.
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Luna, María Celeste, Carlos Roberto Vásquez-Almazán, Julian Faivovich, and Andrés Eduardo Brunetti. "Gland composition in sexually dimorphic skin structures of two species of Hylid frogs: Plectrohyla guatemalensis and Ptychohyla hypomykter." Amphibia-Reptilia 40, no. 4 (2019): 523–29. http://dx.doi.org/10.1163/15685381-20191221.
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Abstract Secondary sexual characters form a diverse group of traits widely spread in amphibians. Within anurans, the Hylini tribe represents an interesting group to examine the evolution of this type of characters because it has different skin structure modifications, including ventrolateral glands, nuptial pads, and unique swollen upper lips. We analysed the skin gland composition in the upper lip of Plectrohyla guatemalensis and the ventrolateral gland of Ptychohyla hypomykter (Hylidae: Hylinae: Hylini). Each of these species is characterized by a different type of sexually dimorphic skin gland; specialized mucous glands (SMGs) in Pl. guatemalensis and specialized serous glands (SSGs) in Pt. hypomykter. The SMGs conform to the general type of sexually dimorphic skin glands in amphibians, whereas SSGs are very rare. Because SMGs are likely involved in the production of sexual pheromones, their distinctive location and their co-occurrence with other secondary sexual characters like long and pointed maxillary and premaxillary teeth in Pl. guatemalensis suggests that the system used for their delivery may be a distinguishing behavioral feature in this species. The presence of both types of glands in Pt. hypomykter (SMGs in nuptial pads, and SSGs in ventrolateral glands) suggests a different or, at least, a complementary role of these two types of glands during reproduction.
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Brito, Pedro, Cíntia P. Targueta, Walquíria Arruda, Fernanda Santos, and Rogério Bastos. "The sexual dimorphic inguinal glands of the frog species Ololygon centralis (Anura: Hylidae) at light and transmission electron microscopy." Zoologia 36 (July 5, 2019): 1–9. http://dx.doi.org/10.3897/zoologia.36.e29356.
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The anuran skin characteristically has different types of glands, most of which are microscopic and are spread throughout the skin. Some species have specialized regions where glands agglomerate, forming macroglands. The description of the external morphology of Ololygoncentralis (Pombal & Bastos, 1996) revealed the presence of an inguinal gland. Ololygoncentralis is the only species of the genus that has a macrogland. The present study found these inguinal macroglands to be present only on male specimens, thus characterizing it as a sexually dimorphic skin gland. Microscopic analysis revealed that these glands are composed of many syncytial units involved by myoepithelial cells. The center of the syncytium is full of a proteinaceous secretion with a basic pH and the absence of sugar residues. Similar glands observed in other anuran species have been associated with pheromone production, suggesting that the inguinal glands described for O.centralis males may have a similar function.
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Hidayat, Rachmat, and Patricia Wulandari. "Anatomy and Physiology of Animal Model Rats in Biomedical Research." Biomedical Journal of Indonesia 7, no. 2 (March 12, 2021): 265–69. http://dx.doi.org/10.32539/bji.v7i2.287.
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A distinguishing feature of rodents, including rats, is the absence of canines and thepresence of prominent incisors. Rats are monophydontic, meaning they grow one setof teeth in their lifetime. The enamel of the rodent incisor contains iron, which givesit its yellow-orange color. Rats are mammals and as such, possess many similaritieswith other mammals. Only the peculiarities of the rat’s anatomy are addressed. Malerats reach puberty at 40 - 60 days of age. Descent of the testes usually occursbetween days 30 - 60. Sperm counts vary by strain. The male rat has an os penis.Male rats have the following accessory sexual organs: ampulla, seminal vesicles,prostate, bulbourethral glands, coagulating glands, and preputial glands. Thecoagulating gland and prostatic and vesicular secretions are responsible for thecopulation plug, a firm plug deposited in the vagina of the female after copulation.(This plug, when found outside the female rat, is capsuleshaped and approximately5 mm long.) The male rat has no nipples. The adult male rat has a prominentscrotum and a longer anogenital distance than the female rat.
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Sakulsak, Natthiya, Tomohiko Wakayama, Wiphawi Hipkaeo, Miyuki Yamamoto, and Shoichi Iseki. "Cloning and Characterization of a Novel Animal Lectin Expressed in the Rat Sublingual Gland." Journal of Histochemistry & Cytochemistry 53, no. 11 (June 13, 2005): 1335–43. http://dx.doi.org/10.1369/jhc.5a6618.2005.
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We cloned a rat gene that is expressed primarily in the sublingual gland and named the predicted 503 amino-acid protein SLAMP (sublingual acinar membrane protein). SLAMP has 63% homology with human ERGIC-53-like protein, a member of the family of animal L-type lectins. Using a cDNA probe for SLAMP mRNA and rabbit antisera against SLAMP, we examined the expression and localization of SLAMP in major rat organs and tissues. With both Northern and Western blot analyses, abundant expression of SLAMP was demonstrated predominantly in the sublingual gland, with single sizes of the mRNA and protein 1.8 kb and 50 kDa, respectively, but not in other organs or tissues, including the parotid and submandibular glands. With immunohistochemistry, SLAMP was localized to the mucous acinar cells, but not to the serous demilunes or the duct system. With immunoelectron microscopy, SLAMP was localized predominantly to regions corresponding to the ER-Golgi intermediate compartment. Besides the sublingual gland, SLAMP immunore-activity was also demonstrated in mucous cells of the minor salivary glands in oral cavity and of Brunner's glands in the duodenum. These results suggested that rat SLAMP plays a specific role in the early secretory pathway of glycoproteins in specific types of mucous cells.
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de Almeida, Pablo G., Flavia A. Felsemburgh, Rodrigo A. Azevedo, and Lycia de Brito-Gitirana. "Morphological re-evaluation of the parotoid glands of Bufo ictericus (Amphibia, Anura, Bufonidae)." Contributions to Zoology 76, no. 3 (2007): 145–52. http://dx.doi.org/10.1163/18759866-07603001.
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Multicellular glands in the amphibian integument represent a significant evolutionary advance over those of fishes. Bufonids have parotoid glands, symmetrically disposed in a post-orbital position. Their secretion may contribute to protection against predators and parasites. This study provides a re-evaluation of the morphology of the Bufo ictericus parotoid glands. The parotoid gland integument of the medial surface shows rounded depressions with small pores that connect with the duct openings of the larger granular glands. Under light microscopic evaluation the integument is constituted by typical epidermis, supported by dermis subdivided into a spongious dermis, a reticular dermis, and a compact dermis. The Eberth-Katschenko layer is identified as a basophilic material scattered throughout the superficial spongious dermis. The parotoid gland is an integument region, in which three exocrine glandular types occur: mixed glands, smaller granular glands and larger granular glands. The mixed gland is formed by mucous and serous cells while the small granular glands contain a homogene acidophilic intake. The larger granular glands produce a basophilic and alcianophilic material, and are responsible for the macroscopic protuberances designed as parotoid glands. Thus, the end product released by the parotoid glands is a mix of secretions produced by the three glands.
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Mouton, le Fras, Alexander Flemming, Michael Bates, and Chris Broeckhoven. "The relationship between generation gland morphology and armour in Dragon Lizards (Smaug): a reassessment of ancestral states for the Cordylidae." Amphibia-Reptilia 39, no. 4 (2018): 457–70. http://dx.doi.org/10.1163/15685381-20181032.
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Abstract To substantiate the claim of a relationship between generation gland morphology and degree of body armour in cordylid lizards, we studied the nine species in the genus Smaug. We predicted that well armoured species in this clade will have multi-layer generation glands, and lightly armoured species two-layer glands. Gland type was determined using standard histological techniques after sectioning a glandular patch of one adult male per species. A total of 133 specimens were examined for data on tail and occipital spine lengths (which were used as indicators of armour). We found that species with multi-layer generation glands (S. giganteus, S. breyeri, and S. vandami) have relatively long tail and occipital spines, while species with two-layer glands (S. mossambicus, S. regius, S. barbertonensis, S. warreni, and an undescribed species) have relatively short spines. Smaug depressus possesses both multi-layer and two-layer glands, and this variation was linked to regional variation in spine length. An ancestral state reconstruction for the Cordylidae showed that the two-layer state always results from the reduction of layers from a multi-layer precursor, and that reduction always culminates in two-layer glands and not in one-layer glands. This finding suggests that the one-layer state in the Ninurta-Chamaesaura-Pseudocordylus clade is most probably plesiomorphic, and therefore the ancestral state at the Cordylidae and Cordylinae nodes. Given the observed relationship between type of generation gland and body armour, this finding would suggest that the most recent common ancestor of the Cordylidae was lightly armoured.
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Wada, Yasuhiro, Shigemi Nakajima, Ryoji Kushima, Shizuki Takemura, Naoko Mori, Hiroshi Hasegawa, Takahisa Nakayama, et al. "Pyloric, pseudopyloric, and spasmolytic polypeptide-expressing metaplasias in autoimmune gastritis: a case series of 22 Japanese patients." Virchows Archiv 479, no. 1 (January 30, 2021): 169–78. http://dx.doi.org/10.1007/s00428-021-03033-5.
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AbstractThere are two types of pyloric gland-like metaplasia in the corpus of stomach: pyloric and pseudopyloric metaplasias. They show the same morphology as the original pyloric glands in H&E staining. Pseudopyloric metaplasia is positive for pepsinogen (PG) I immunohistochemically, whereas pyloric metaplasia is negative. Recently, spasmolytic polypeptide-expressing metaplasia (SPEM) is proposed for pyloric gland-like metaplasia mainly in animal experiments. SPEM expresses trefoil factor family 2 (TFF2) and is often considered synonymous with pseudopyloric metaplasia. We reviewed consecutive 22 Japanese patients with autoimmune gastritis (AIG) to investigate TFF2 expression in pyloric and pseudopyloric metaplasias by counting all pyloric gland-like glands in biopsy specimens taken from greater curvature of the middle corpus according to the Updated Sydney System. Pyloric metaplasia was seen in all the 22 cases, and pseudopyloric metaplasia was found in 15 cases. Of 1567 pyloric gland-like glands in all the cases, 1381 (88.1%) glands were pyloric metaplasia glands, and the remaining 186 (11.9%) glands were pseudopyloric metaplasia glands. TFF2 expression was observed in pyloric or pseudopyloric metaplasia glands in 20 cases. TFF2 expression was recognized in 409 of 1381 (26.9%) pyloric metaplasia glands and 27 of 186 (14.5%) pseudopyloric metaplasia glands (P<0.01, chi-square test). In conclusion, SPEM was not always the same as pseudopyloric metaplasia in human AIG, and the majority of metaplasia in AIG was not pseudopyloric but pyloric metaplasia.
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Booth, W. D., E. Diane Williamson, and R. L. S. Patterson. "16-androstene steroids in the submaxillary salivary gland of the boar in relation to measures of boar taint in carcasses." Animal Science 42, no. 1 (February 1986): 145–52. http://dx.doi.org/10.1017/s0003356100017839.
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ABSTRACTFifteen Large White boars were randomly allocated to three groups of five pigs. The boars were slaughtered over a period of time at one of three live weights: group 1 (pork weight), 63 to 68 kg (mean age 141 days), group 2 (bacon weight), 90 to 97 kg (mean age 203 days) and group 3 (heavy weight), 121 to 133 kg (mean age 268 days). Testes, bulbourethral glands, submaxillary salivary glands, blood and thoracic fat were taken from each pig and the glands weighed and steroids determined in extracts of the submaxillary glands, blood plasma and fat. Testosterone and the boar taint steroid, 5a-androstenone (5a-androst-16-en-3-one) were measured in plasma by radioimmunoassay (RIA). 3a-androstenol (5a-androst-16-en-3a-ol) and 5a-androstenone were determined separately in submaxillary glands by gas-liquid chromatography and together semi-quantitatively by a colour reaction. 5a-androstenone was also determined in submaxillary glands by RIA and in fat by enzyme-linked immunosorbent assay. Mean somatic characteristics differed significantly between the groups, but due to the wide variation in steroid concentrations between individual boars, mean differences for steroid concentrations between groups were not significant.Significant positive correlations were found in boars between bulbourethral gland weight, submaxillary gland weight, concentrations of 3a-androstenol and 5a-androstenone in the submaxillary gland and concentrations of free plasma 5a-androstenone and fat 5a-androstenone (P < 0·05). The application of a simple colour reaction to detect readily extractable 16-androstene steroids (16-androstenes) in submaxillary gland tissue is discussed in relation to other methods for determining boar taint.
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da Cruz-Landim, Carminda, and Silvana Beani Poiani. "Cephalic salivary gland ultrastructure of worker and queen eusocial bees (Hymenoptera, Apidae)." Animal Biology 59, no. 3 (2009): 299–311. http://dx.doi.org/10.1163/157075609x454935.
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AbstractEusocial bees present a pair of functional salivary glands in head, the cephalic salivary glands. These glands from workers and queens of two eusocial bee species, Apis mellifera and Scaptotrigona postica, were examined at different life stages using routine transmission electron microscopy techniques to correlate morphology and gland functions. Ultrastructural features of worker and queen glands ducts and secretory units were descriptively compared between species. The duct cells present basal plasma membrane invaginations reaching the apical region. Intercellular space and invaginations contain material of similar electron-density to the basal lamina, suggesting that substances might be directly absorbed from the hemolymph to the gland lumen. The secretory cells are rich in smooth endoplasmic reticulum, mitochondria, Golgi, and vesicles typical of lipid secretion. Secretory cells in S. postica become flattened with age in contrast to A. mellifera, where cells remained cuboidal. Mitochondria are associated with secretory vesicles and may become lipid deposits. A possible role of worker and queen secretion is discussed, taking changes in caste gland morphology and their function in the colony into account.
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Rehorek, S. J., M. N. Hutchinson, and B. T. Firth. "Testing the orbital lubrication hypothesis: the Harderian glands in burrowing skinks (Reptilia: Squamata)." Canadian Journal of Zoology 87, no. 4 (April 2009): 356–65. http://dx.doi.org/10.1139/z09-021.
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The Harderian gland is an orbital gland thought to be a source of corneal lubricant, supplementary to the other orbital glands. This study investigated the possible role of skink Harderian glands in corneal lubrication. It was hypothesized that if these glands play a role in corneal lubrication, then the structure of these glands would be affected by structural orbital modifications. We examined the Harderian and lacrimal glands of five species of Australian skinks (Lygosominae), two of which possessed orbital modifications in the form of a transparent immoveable eyelid (spectacle) and skull reduction. All species possessed well-developed posterior lacrimal glands, but no anterior lacrimal glands. Anatomically, the Harderian glands were smaller in the burrowing species relative to the nonburrowing species. No other obvious species-specific differences were observed. The absence of any differentiation at the microscopic level suggests that although there is some change in the relative amount of secretant produced, the nature of the secretion studied by classical histochemistry remains essentially unchanged. However, at higher taxonomic levels, the size and structure of the Harderian gland may be taxon-specific and unrelated to the orbital environment. Thus, orbital lubrication may not necessarily be the sole function of the Harderian gland.
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Brizzi, R., C. Calloni, and G. Delfino. "Tail base glands in European plethodontid salamanders with some comments on their biological and phylogenetic significance." Amphibia-Reptilia 12, no. 4 (1991): 357–72. http://dx.doi.org/10.1163/156853891x00013.
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AbstractBoth the males and females of Speleomantes flavus, S. genei, S. imperialis and S. supramontis possess gland clusters in the dorsal skin of the tail base, consisting of large, closely contiguous, serous or mixed units. Structural and ultrastructural investigations revealed consistent homogeneous features in the glands from the four species and obvious homologies between these and the serous and mixed cutaneous glands of the back skin. Seasonal changes were not observed in the secretory activity of the tail base glands. It is suggested on the basis of these findings that tail base glands play a role possibly involving defensive strategies or, alternatively, the production of pheromone-like substances which may help the animals to recognize each other. The occurrence of tail base glands in both plethodontid subfamilies and respective tribes, found in the present study and bibliographical data, is regarded as a symplesiomorphy. Further suggestions on the phylo. genetic significance of this anatomical character may, however, be derived from its distinctive occurrence and functional role in the various plethodontid groups. Present findings suggest that tail base glands represent a plesiomorphous character in the Speleomantes species observed, whereas the condition of these gland clusters, described in some New World Plethodontidae, is assumed as a synaphomorphy.
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Carvalho, Thaís Isabela, Julia Klaczko, and Veronica Slobodian. "Pectoral-fin glands and delivery apparatus in the catfish genus Brachyrhamdia Myers, 1927 (Siluriformes: Heptapteridae)." Papéis Avulsos de Zoologia 61 (August 24, 2021): e20216174. http://dx.doi.org/10.11606/1807-0205/2021.61.74.
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The Siluriformes, popularly known as catfishes, are probably the vertebrate group with the highest diversity of venomous animals, even though only approximately a hundred venomous catfishes are reported to date. Venomous catfishes might present a delivery system apparatus, formed by an unbranched ray at the leading edge of pectoral and dorsal fins (spine), which can be stiffened and pungent, while venom glands can be present at the surface of such spines and/or the axillary region. This work investigated the presence, morphology and distribution of glands and pectoral-fin delivery apparatus in the heptapterid Brachyrhamdia genus. Pectoral-fin spine external morphology was compared across all valid species in the genus, histological sections of the pectoral-fin spine and axillary regions of B. heteropleura and B. marthae were produced, and dissections of the pectoral girdle region of the mentioned species were analyzed. The histological sections confirmed the presence of pectoral-fin glands at the surface of the pectoral-fin spine of Brachyrhamdia species, and cellular morphology indicates these glands are probably venomous. Also, we found a piriform gland at the axillary region, whose cell morphology is like the reported for other catfishes. However, we cannot currently confirm or deny axillary gland participation in the venom delivery apparatus. This work constitutes the first report of venom glands in Brachyrhamdia, and the first description of Heptapteridae axillary glands.
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DILEK, OMER GURKAN, ROSEN STEFANOV DIMITROV, KAMELIA DIMCHEVA STAMATOVA-YOVCHEVA, DAVID GOSPODINOV YOVCHEV, and RADOSLAV MIHAYLOV. "Importance for experiments in human medicine of imaging modalities for macroanatomical and histological study of rabbit suprarenal glands." Medycyna Weterynaryjna 75, no. 08 (2019): 6286–2019. http://dx.doi.org/10.21521/mw.6286.
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The morphological characteristics of the rabbit adrenal glands are currently investigated using routine imaging modalities. The aim of the study was to collect and interpret major findings and information in the literature on the rabbit as an animal model for investigations in humans. The suprarenal glands of thirty-four mature, clinically healthy New Zealand rabbits were studied using anatomical, routine histology, radiology, computed tomography, ultrasonography, and magnetic resonance imaging methods. The results demonstrated that the rabbit suprarenal glands are paired ellipsoid organs. The right gland was close to the right kidney, whereas the left gland was located at a distance from the left kidney. The capsule was composed of dense connective tissue. The parenchyma consisted of three zones: zona glomerulosa, zona fasciculate, and zona reticularis. The medulla was in the center of the glandular parenchyma. The glands’ radiological and CT features defined their position relative to the right and left kidneys. The right suprarenal gland was with normal attenuation. The left suprarenal gland was located at a distance from the left kidney. The US features of the glands demonstrated variability in darkness and contrast, revealing specific histological features. The MRI peculiarities of the glands defined them as well visible findings
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Staddon, BW, MJ Thorne, and DW Knight. "The Scent Glands and Their Chemicals in the Aposematic Cotton Harlequin Bug, Tectocoris-Diophthalmus (Heteroptera, Scutelleridae)." Australian Journal of Zoology 35, no. 3 (1987): 227. http://dx.doi.org/10.1071/zo9870227.
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In describing differences in morphology, developmental fate and secretion composition in the scent glands of the cotton harlequin bug Tectocoris diophthalmus we have sought to extend comparative knowledge of the scent gland system in the pentatomoid families within the Hemiptera-Heteroptera. Chemical investigation of the secretions was undertaken by coupled gas chromatography-mass spectrometry (GC-MS). The following volatiles were detected: 2-hexenal, 2-hexenyl acetate and 2- octenyl acetate from the metathoracic scent gland (an adult gland); nonanal from the abdominal dorsal first gland (the divided dorsal gland) in the adults; 2-hexenal, 2-octenal, 4-oxohex-2-enal, dodecane and tridecane from the abdominal dorsal second and third glands (the undivided dorsal glands) in fifth-instar nymphs. Secretory units are sparse, opener muscles absent, and secretion scarcely, if at all, present in the second and third dorsal abdominal scent glands in the adults. T. diophthalmus is an addition to the small but growing list of pentatomoids in which biochemical divergence of the abdominal dorsal first gland from the abdominal dorsal second and third glands has been reported. The metathoracic scent gland in T. diophthalmus is comparatively small, as it is in many other aposematic species within the Hemiptera-Heteroptera.
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Martínez-Alós, S., P. García-Corrales, and B. Cifrian. "Ultrastructural study of frontal glands in Bothromesostoma personatum (Platyhelminthes, Typhloplanoida)." Canadian Journal of Zoology 72, no. 4 (April 1, 1994): 707–11. http://dx.doi.org/10.1139/z94-095.
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The frontal glands of Bothromesostoma personatum were examined using transmission electron microscopy. These glands have two types of rhabdoid gland cells; one type produces rhabdites and the other a different type of rod secretion (rhabdoids). The ultrastructure of the latter type is described, together with their origin. Long necks containing the rhabdoids emerge from the rhabdoid gland cell bodies and extend to the anterior end of the animal, where they release the rhabdoids. The rhabdoids are compared with the rhammites of other rhabditophoran species on the basis of their dye affinities, formation mechanism, and ultrastructure.
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Salisbury, S., and M. S. Bauer. "Reconstruction of Distal Hind Limb Injuries in Cats Using the Caudal Superficial Epigastric Skin Flap." Veterinary and Comparative Orthopaedics and Traumatology 08, no. 02 (1995): 98–101. http://dx.doi.org/10.1055/s-0038-1632436.
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SummaryFour cats were admitted for treatment of traumatic wounds distal to the tarsus. The caudal superficial epigastric skin flap was used to reconstruct each wound. In two cats, an initial flap that included all four mammary glands was attempted, but the segment of the flap that incorporated the first mammary gland underwent necrosis. Caudal superficial epigastric flaps that included mammary glands ## 2, 3 and 4 survived completely in three cats. In one cat the distal 3.0 cm, including the second mammary gland, underwent necrosis after a seroma formed. These flaps covered defects that extended beyond the tarsus in all cats and to the digits in two cats.Four cats with traumatic wounds distal to the tarsus underwent reconstructive surgery. Caudal superficial epigastric flaps that included mammary glands ## 2, 3 and 4 were used to reconstruct the wounds. In two cats, all four mammary glands were initially included with the flap. In these two cats, the distal portions of the flaps including the first mammary gland underwent necrosis. The necrotic areas were debrided and the flaps were repositioned to cover the defects. The remainder of these flaps and one flap that included mammary glands ## 2–4 survived completely. All flaps covered defects that extended beyond the tarsus in all cats and to the digits in two cats.
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Delfino, Giovanni, Gianfranco Tanteri, and Rossana Brizzi. "Cloacal anatomy of the palmate newt, Triturus helveticus (Amphibia, Salamandridae)." Amphibia-Reptilia 25, no. 3 (2004): 233–45. http://dx.doi.org/10.1163/1568538041975152.
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AbstractThe cloacal anatomy of the palmate newt, Triturus helveticus, was studied in both sexes using light and scanning electron microscopes. The female cloaca is characterized by the occurrence of rugae and folds. Two folds are especially prominent in the region where the spermathecal tubules open into the cloaca. In addition to sperm storage structures, vent glands are obvious in the connective tissue around the cloacal orifice. Their pores occur externally to the cloacal borders, thus suggesting that these glands are a possible source of mating pheromones. Typical features of the male cloaca are: a ciliated epithelium; a cloacal tube dorsal and separate from the anterior cloacal chamber; a broad pseudopenis and wide lateral recesses in the cloacal chamber. Four main types of cloacal glands are recognized in males (dorsal, pelvic, Kingsbury's, and ventral gland). Quite unusual is the occurrence of two distinct types of dorsal glands, possibly related to the production of different pheromonal substances. These glands in the male, together with the occurrence of vent glands in the female, are proposed as cloacal specializations for the production of unequivocal species-specific sex attractants.
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Zeng, Fang, Sha Liao, Zhe Kuang, Qingchun Zhu, Hengxi Wei, Junsong Shi, Enqin Zheng, et al. "Genetically Engineered Pigs as Efficient Salivary Gland Bioreactors for Production of Therapeutically Valuable Human Nerve Growth Factor." Cells 11, no. 15 (August 2, 2022): 2378. http://dx.doi.org/10.3390/cells11152378.
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Farm animal salivary glands hold great potential as efficient bioreactors for production of human therapeutic proteins. Nerve growth factor (NGF) is naturally expressed in animal salivary glands and has been approved for human clinical treatment. This study aims to employ transgenic (TG) pig salivary gland as bioreactors for efficient synthesis of human NGF (hNGF). hNGF-TG pigs were generated by cloning in combination with piggyBac transposon-mediated gene transfer. These hNGF-TG pigs specifically expressed hNGF protein in their salivary glands and secreted it at high levels into saliva. Surgical and nonsurgical approaches were developed to efficiently collect saliva from hNGF-TG pigs. hNGF protein was successfully purified from collected saliva and was verified to be biologically active. In an additional step, the double-transgenic pigs, where the endogenous porcine NGF (pNGF) gene was replaced by another copy of hNGF transgene, were created by cloning combined with CRISPR/Cas9-mediated homologous recombination. These double-transgenic pigs expressed hNGF but not pNGF, thus avoiding possible “contamination” of hNGF with pNGF protein during purification. In conclusion, TG pig salivary glands can be used as robust bioreactors for a large-scale synthesis of functional hNGF or other valuable proteins. This new animal pharming method will benefit both human health and biomedicine.
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Epstein, M. S., and D. G. Blackburn. "Histology and histochemistry of androgen-stimulated nuptial pads in the leopard frog, Rana pipiens, with notes on nuptial gland evolution." Canadian Journal of Zoology 75, no. 3 (March 1, 1997): 472–77. http://dx.doi.org/10.1139/z97-057.
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Nuptial pads are digital specializations of male frogs that cycle with the reproductive season and are considered to function in mating. Glandular secretions of the nuptial pads were analyzed histochemically in androgen-stimulated overwintering leopard frogs, Rana pipiens, to provide information on gland function and physiological control. In castrated and sham-operated male frogs treated with testosterone cypionate, the secretory product of the nuptial gland epithelium stained positive for carbohydrates and proteins, yet negative for lipids and glycogen. Secretions also stained positive for tyrosine residues and negative for acidic mucosubstances, sulphated mucosubstances, tryptophan, and cystine. Castration prior to hormone treatment had no effect on gland staining properties, and glands of cholesterol-treated castrates and intact controls appeared to be inactive cytochemically. Nuptial glands of frogs treated with 5-α-dihydrotestosterone were histologically similar to those of frogs treated with testosterone cypionate. Nuptial glands share structural and functional characteristics with integumentary mucous glands, and may have been modified evolutionary from that parent gland population.
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Fang, Rendong, Jingchun Cui, Tengteng Cui, Haiyong Guo, Hisaya Ono, Chun-Ho Park, Masashi Okamura, Akio Nakane, and Dong-Liang Hu. "Staphylococcal Enterotoxin C Is an Important Virulence Factor for Mastitis." Toxins 11, no. 3 (March 2, 2019): 141. http://dx.doi.org/10.3390/toxins11030141.
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Staphylococcus aureus is an important bacterial pathogen causing bovine mastitis, but little is known about the virulence factor and the inflammatory responses in the mammary infection. Staphylococcal enterotoxin C (SEC) is the most frequent toxin produced by S. aureus, isolated from bovine mastitis. To investigate the pathogenic activity of SEC in the inflammation of the mammary gland and the immune responses in an animal model, mouse mammary glands were injected with SEC, and the clinical signs, inflammatory cell infiltration, and proinflammatory cytokine production in the mammary glands were assessed. SEC induced significant inflammatory reactions in the mammary gland, in a dose-dependent manner. SEC-injected mammary glands showed a severe inflammation with inflammatory cell infiltration and tissue damage. In addition, interleukin (IL)-1β and IL-6 production in the SEC-injected mammary glands were significantly higher than those in the PBS control glands. Furthermore, the SEC-induced inflammation and tissue damage in the mammary gland were specifically inhibited by anti-SEC antibody. These results indicated, for the first time, that SEC can directly cause inflammation, proinflammatory cytokine production, and tissue damage in mammary glands, suggesting that SEC might play an important role in the development of mastitis associated with S. aureus infection. This finding offers an opportunity to develop novel treatment strategies for reduction of mammary tissue damage in mastitis.
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Kuzniak, Nataliya B., Roman R. Dmytrenko, Larysa Ya Fedoniuk, Svitlana I. Boitsaniuk, Liudmyla V. Kuzniak, Andrii V. Yavorskyi, and Stepan V. Tkachyk. "DEVELOPMENT OF THE INNER NASAL CAVITY IN ANIMALS IN PHYLO- AND ONTOGENESIS: FUNCTIONAL ANATOMIC SIGNIFICANCE IN THE DEVELOPMENT PERIOD." Wiadomości Lekarskie 72, no. 3 (2019): 432–35. http://dx.doi.org/10.36740/wlek201903121.
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Іntroduction: Main functions of the inner nose in humans are respiration and olfaction. Therefore, human needs a large surface of inhalable and exhalable air contact, warming and moistening. Importance of these organs in animals in phylogenesis before and after the secondary palate development can explain their anatomic and functional designation. The aim is to find out the functional significance of some anatomic formations of the inner nose and their development peculiarities in phylo-and ontogenesis. Materials and methods: We used a comparative anatomy method where we compared well-known facts of different animals’ development before and after secondary palate formation in phylo- and ontogenesis. Review: Olfactory organ in lower vertebrates develops as canal with two openings through which as a result of water penetration the olfactory ability increases. Sinuses formation in animals happens after secondary palate formation. Secondary palate in embryo develops by second month of development, and sinuses’ development begins on the 3-4 month. As a result, upper jaws and facial skull became stronger. Importance of mucous and lacrimal glands of the nose cavity and mucous glands of mouth received new functions of animal and vegetable food digestion. Conclusions: development of the secondary palate in warm-blooded vertebrates changed (limited) functional applicability of the lacrimal gland and nasolacrimal canal, mucous glands of nose and vegetative innervation. Groups of lacrimal, mucous glands of nose and mouth are unified system of primary, neurosecretory reaction to environment.
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STELWAGEN, K., B. W. McBRIDE, D. G. GRIEVE, and R. A. TOWNER. "NUCLEAR MAGNETIC RESONANCE IMAGING AND PROTON SPECTROSCOPY USED AS A TECHNIQUE TO ASSESS MAMMARY GLAND COMPOSITION IN HOLSTEIN HEIFERS." Canadian Journal of Animal Science 70, no. 4 (December 1, 1990): 1151–54. http://dx.doi.org/10.4141/cjas90-141.
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Mammary glands of eight nonpregnant, nulliparous Holstein heifers (416 ± 11 d) were used to study the potential for nuclear magnetic resonance (NMR) imaging and proton spectroscopy as a technique to assess mammary gland composition. It was concluded that the NMR technique has the potential to quantitate mammary gland composition in heifers. Key words: Nuclear magnetic resonance imaging and spectroscopy, mammary composition, Holstein heifers
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Anderson, Matthew J., and Alan F. Dixson. "Sexual selection affects the sizes of the mammalian prostate gland and seminal vesicles." Current Zoology 55, no. 1 (February 1, 2009): 1–8. http://dx.doi.org/10.1093/czoolo/55.1.1.
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Abstract The accessory reproductive glands of male mammals contribute the bulk of the secretions in which spermatozoa are transported to the female tract during copulation. Despite their morphological diversity, and the chemical complexity of their products, little is known about the possible effects of sexual selection upon these glands in mammals. Here we consider the seminal vesicles and prostate glands in a sample of 89 species and 60 genera representing 8 Orders of mammals. The sizes of the accessory glands are analysed in relation to body weight and testes weight. Both the seminal vesicles size and prostate size (corrected for body weight) correlate positively with relative testes size in this sample; this finding remains highly significant after application of procedures to correct for possible phylogenetic biases in the data set. The accessory reproductive glands are also significantly larger in those mammals which have large relative testes sizes, and in which the likelihood of sperm competition is greatest. These results support the hypothesis that sexual selection has played an important role in the evolution of the mammalian prostate gland and seminal vesicles.
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Palin, M. F., D. Beaudry, C. Roberge, and C. Farmer. "Expression levels of STAT5A and STAT5B in mammary parenchymal tissue from Upton-Meishan and Large White gilts." Canadian Journal of Animal Science 82, no. 4 (December 1, 2002): 507–18. http://dx.doi.org/10.4141/a01-091.
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The implication of STAT5A and STAT5B in mammary gland development and maintenance of lactation is well documented in rodents and humans. However, little is known regarding their roles in mammary gland development during gestation in pigs. We identified and analyzed the complete coding sequences of swine STAT5A and STAT5B and evaluated their mRNA levels in mammary glands of gestating gilts (day 110) in two different breeds, Upton-Meishan and Large White. Sequence analysis revealed a new APASA insertion in the STAT5A amino acid sequence that is in close proximity to residue Tyr 699 and whose phosporylation leads to the activation of target genes’ transcription. STAT5A mRNA levels were higher in Upton-Meishan than in Large White. In both breeds, STAT5B mRNA levels were higher than those of STAT5A , which is contrary to what was found in other mammals. A correlation between circulating IGF-I levels and STAT5B mRNA levels in the mammary gland was noticed in the Upton-Meishan breed only. STAT5B mRNA levels in mammary tissue of Large White gilts were highly correlated with extra-parenchymal tissue weight, parenchymal tissue weight, total parenchymal DNA, RNA and RNA/DNA ratio. In Upton-Meishan gilts, correlations were observed only between extra-parenchymal weight and STAT5A and STAT5B mRNA levels. These results indicate that there are significant differences in mRNA levels of STAT5A and STAT5B in the mammary glands of pregnant gilts when compared to other mammals, and between swine breeds. Key words: Mammary glands, signal transducers, pregnancy, kinases, pig, expression
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D’Ambrosio, Mariaelena, Cátia Gonçalves, Mariana Calmão, Maria Rodrigues, and Pedro M. Costa. "Localization and Bioreactivity of Cysteine-Rich Secretions in the Marine Gastropod Nucella lapillus." Marine Drugs 19, no. 5 (May 15, 2021): 276. http://dx.doi.org/10.3390/md19050276.
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Marine biodiversity has been yielding promising novel bioproducts from venomous animals. Despite the auspices of conotoxins, which originated the paradigmatic painkiller Prialt, the biotechnological potential of gastropod venoms remains to be explored. Marine bioprospecting is expanding towards temperate species like the dogwhelk Nucella lapillus, which is suspected to secrete immobilizing agents through its salivary glands with a relaxing effect on the musculature of its preferential prey, Mytilus sp. This work focused on detecting, localizing, and testing the bioreactivity of cysteine-rich proteins and peptides, whose presence is a signature of animal venoms and poisons. The highest content of thiols was found in crude protein extracts from the digestive gland, which is associated with digestion, followed by the peribuccal mass, where the salivary glands are located. Conversely, the foot and siphon (which the gastropod uses for feeding) are not the main organs involved in toxin secretion. Ex vivo bioassays with Mytilus gill tissue disclosed the differential bioreactivity of crude protein extracts. Secretions from the digestive gland and peribuccal mass caused the most significant molecular damage, with evidence for the induction of apoptosis. These early findings indicate that salivary glands are a promising target for the extraction and characterization of bioactive cysteine-rich proteinaceous toxins from the species.
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Lauteri, Eleonora, Jole Mariella, Francesca Beccati, Ellen Roelfsema, Carolina Castagnetti, Marco Pepe, Tanja Peric, et al. "Adrenal Gland Ultrasonographic Measurements and Plasma Hormone Concentrations in Clinically Healthy Newborn Thoroughbred and Standardbred Foals." Animals 11, no. 6 (June 19, 2021): 1832. http://dx.doi.org/10.3390/ani11061832.
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Adrenal hormones, ACTH plasma concentrations and the ultrasonographic evaluation of the adrenal glands are considered complementary in clinical evaluations of the hypothalamic–pituitary–adrenal (HPA) axis function in several species. In dogs, age, size and weight have a significant effect on the ultrasonographic size of the adrenal glands. In neonatal foals, ultrasonographic evaluation and measurements of the adrenal glands have been demonstrated to be reliable; however, the effect of individual variables on ultrasonographic features has not been investigated, and the clinical usefulness of adrenal gland ultrasonography is still not known. The aims of this study were: (i) to provide and compare adrenal glands ultrasound measurements in healthy newborn Thoroughbred and Standardbred foals, and assess any effect of age, weight and sex on them; (ii) to assess and compare ACTH and steroid hormone concentrations in healthy neonatal foals of the two breeds. Venous blood samples and ultrasonographic images of the adrenal glands were collected from 10 healthy neonatal Thoroughbred and 10 healthy neonatal Standardbred foals. Ultrasonographic measurements of the adrenal glands were obtained and adrenocorticotropin (ACTH), cortisol, dehydroepiandrosterone (DHEA), progesterone (P4) and aldosterone plasma concentrations were assessed. The ACTH/cortisol, ACTH/progesterone, ACTH/aldosterone, ACTH/DHEA and cortisol/DHEA ratios were calculated. A significant positive correlation was found between the height of the right adrenal gland and the foal’s weight; the width of the right and left adrenal gland and the medulla was significantly lower in Thoroughbreds than in Standardbreds. Cortisol and ACTH plasma concentrations were significantly higher and lower, respectively, in Thoroughbreds compared with Standardbreds. The cortisol/DHEA ratio was significantly higher in Thoroughbreds. This study provides reference ranges for neonatal Thoroughbred and Standardbred foals, and suggests the presence of breed-related differences in ultrasonographic adrenal gland measurements, plasmatic cortisol and ACTH concentrations. The higher cortisol/DHEA ratio detected in Thoroughbred foals could suggest a different response to environmental stimulation in the two breeds.
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Park, M. K., R. C. Garrad, G. A. Weisman, and J. T. Turner. "Changes in P2Y1 nucleotide receptor activity during the development of rat salivary glands." American Journal of Physiology-Cell Physiology 272, no. 4 (April 1, 1997): C1388—C1393. http://dx.doi.org/10.1152/ajpcell.1997.272.4.c1388.
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Experiments that used dispersed salivary gland cells from 1-day-old rats indicated the presence of the P2Y nucleotide receptor subtype, P2Y1, based on the agonist potency profile for mobilization of intracellular free Ca2+ [2-methylthio-ATP > ADP > adenosine 5'-O-(2-thiodiphosphate) > ATP, with UTP ineffective] and sequence analysis of reverse transcription-polymerase chain reaction (RT-PCR) products obtained with P2Y1 receptor-specific primers. P2Y1 receptor activity appears to be developmentally regulated, since Ca2+ mobilization in response to the P2Y1-selective agonist, 2-methylthio-ATP, decreased as animal age increased, with the maximal response of 129 +/- 23 nM obtained in 1-day-old animals, decreasing to 30 +/- 3 nM in 4-wk-old animals. However, the abundance of P2Y1 receptor mRNA, assessed by semiquantitative RT-PCR, did not change over this time period, suggesting that receptor activity is regulated by some mechanism other than changes in steady-state levels of P2Y1 receptor mRNA. These findings indicate that functional P2Y1 nucleotide receptors are expressed in immature salivary glands and that receptor activity decreases as the glands mature, suggesting that P2Y1 receptors may have an important role during salivary gland development.
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Bell, S., J. E. Bron, and C. Sommerville. "The distribution of exocrine glands in Lepeophtheirus salmonis and Caligus elongatus (Copepoda: Caligidae)." Contributions to Zoology 69, no. 1-2 (2000): 9–20. http://dx.doi.org/10.1163/18759866-0690102001.
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The morphology, function and distribution of exocrine glands of copepods have rarely been studied in detail and almost nothing is known about them in the sea lice species L. salmonis and C. elongatus. This study utilised a novel application of a light-microscopy staining technique to reveal a variety of glands m nauplius, copepodid, chalimus, preadult and adult stages. The stain, 3’,3-diaminobenzidine tetrahydrochloride (DAB), applied to fresh material, differentiated a population of exocrine glands and enabled a study of their distribution. The stain was successful in highlighting the ducts and pores associated with the larger glands. The locations of gland sub-populations were conserved in all life-stages, although glands in the swimming legs were found to be better represented in mobile and free-swimming stages i.e. copepodids, preadults and adults. Glands associated with the mouth-tube were also located. Other, non-glandular, peroxidase-positive regions were also highlighted by the stain. These regions were found mainly in preadult and adult stages where they formed characteristic bi-symmetrical patterns on the cuticle of the dorsal surface. A study of some calanoid copepods suggested that peroxidase-positive glands are a feature peculiar to caligid copepods. This staining technique has proven useful for elucidating the ontogeny of gland populations in caligids.
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Cao, W., Y. Su, N. Liu, Y. Peng, C. Diao, and R. Cheng. "Location and Vascular Classification of 188 parathyroid glands in New Zealand White Rabbits." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 73, no. 2 (March 2021): 377–82. http://dx.doi.org/10.1590/1678-4162-11760.
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ABSTRACT The function and protection of the parathyroid glands are increasingly popular research topics. New Zealand white rabbits are the most commonly used animal model of parathyroid ischemia. However, information on the vasculature of their parathyroid glands is limited. We used 94 healthy New Zealand white rabbits, 3-4 months of age and 2-3kg in weight, for exploration of the parathyroid glands, which were stained using hematoxylin and eosin (HE) after removal. The following types were classified according to the relationship between the position of the inferior parathyroid gland and the thyroid: Type A, Close Type, Type B, and Distant Type. There were 188 cases, 4 where the inferior parathyroid glands were located near the dorsal side of thyroid (2.13%), 8 where the inferior parathyroid glands were located superior to the upper pole of the thyroid (4.26%), 20 where the inferior parathyroid glands were located parallel to the thyroid (10.64%), and 155 cases where the inferior parathyroid glands were located inferior to the lower pole of thyroid (82.45%). Identifying the location and classifying the vasculature of the parathyroid glands in New Zealand white rabbits will provide an anatomical model to assist in future research.
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Franklin, Craig E., Greg Taylor, and Rebecca L. Cramp. "Cholinergic and adrenergic innervation of lingual salt glands of the estuarine crocodile, Crocodylus porosus." Australian Journal of Zoology 53, no. 6 (2005): 345. http://dx.doi.org/10.1071/zo05001.
Full textAbstract:
Many marine reptiles and birds possess extrarenal salt glands that facilitate the excretion of excess sodium and chloride ions accumulated as a consequence of living in saline environments. Control of the secretory activity of avian salt glands is under neural control, but little information is available on the control of reptilian salt glands. Innervation of the lingual salt glands of the salt water crocodile, Crocodylus porosus, was examined in salt water-acclimated animals using histological methods. Extensive networks of both cholinergic and adrenergic nerve fibres were identified close to salt-secreting lobules and vasculature. The identification of both catecholamine-containing and cholinergic neurons in the salt gland epithelium and close to major blood vessels in the tissue suggests the action of the neurotransmitters on the salt-secreting epithelium itself and the rich vascular network of the lingual salt glands.
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Gray, David R., Peter F. Flood, and Janice E. Rowell. "The structure and function of muskox preorbital glands." Canadian Journal of Zoology 67, no. 5 (May 1, 1989): 1134–42. http://dx.doi.org/10.1139/z89-163.
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The preorbital gland of the muskox is a relatively large pear-shaped structure lying rostral to the eye between the skin and the lacrimal bone. It surrounds a narrow tubular invagination of the skin, which conveys the largely aqueous secretion to the surface of the face. This tube, which enters the gland at its rostrolateral extremity and runs caudodorsally, is partially filled with stiff hairs that arise from follicles in its wall. Most of the gland consists of tightly packed apocrine sweat glands, but large sebaceous glands are associated with the hair follicles of the central tube. The myoepithelium of the sweat glands is highly developed but the facial muscles overlying the gland are very thin and probably do not contribute significantly to the expulsion of secretion. Secretion is mechanically expressed when the animal rubs the area of the gland on something firm such as its own foreleg (gland rubbing) or a prominent object in the environment (rubbing). The gland is functional in both sexes throughout the year but is much larger in males. In the wild, scent marking and gland rubbing occur during aggressive encounters between individuals within a herd, between herds, and between muskoxen and other species. Gland rubbing in females and subadults is usually restricted to interspecific encounters but in males it occurs in most intense agonistic situations. Wild calves performed the self-marking behaviour as early as 1 week of age when play fighting. Captive muskoxen did not rub their preorbital gland on the foreleg but commonly rubbed it on objects. The authors believe that the principal function of the preorbital gland is to provide an olfactory component of the threat behaviour pattern.
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Maya, S., A. R. Sreeranjini, C. Leena, N. S. Sunil Kumar, K. B. Sumena, and Irshad A. "Histology, lectin histochemistry and ultrastructure of interdigital gland in crossbred sheep." Issue 2 (November - December) 1, no. 2 (December 20, 2020): 112–16. http://dx.doi.org/10.51128/jfas.2020.a020.
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Abstract: Histology, lectin histochemistry and ultrastructure of interdigital gland in sheep was studied using six adult cross bred sheep of either sex collected from the Meat Technology Unit, College of Veterinary and Animal Sciences, Mannuthy. The manus and pes were detached from the rest of limbs and after recording the gross observations, the interdigital glands were fixed in 10 per cent neutral buffered formalin and processed for histological examinations. Stratified squamous epithelium with a prominent keratin layer lined the lumen, similar to the skin over the dorsal surface of manus and pes. The epidermis presented mucosal folds, which projected into the lumen. The dermis contained small sebaceous glands, hair follicles of different sizes, arrector pili muscles and apocrine sweat glands. The secretory epithelium of sweat glands was lined with a simple layer of cuboidal and relatively flattened cells. The excretory ducts of these glands were lined by cuboidal cells, with darker appearance than its secretory portion. The fibrous capsule was composed of dense connective tissue with collagen, adipose cells, blood vessels and nerve fibers. Glandular secretion and the granules in the stratum granolosum of the surface squamous epithelium showed positive reaction for lectin Ulex europaeus (UEA-I). The apocrine nature of sweat glands was revealed in the ultrastructural studies by scanning electron microscope. Keywords: Interdigital gland, sheep, histology, lectin histochemistry and ultrastructure
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Wierenga, Pieter K., Isabelle Lombaert, Willy Visser, Harm H. Kampinga, Gerald de Haan, and Rob P. Coppes. "Bone Marrow-Derived Stem Cells Reduce Radiation-Induced Damage to Salivary Glands." Blood 104, no. 11 (November 16, 2004): 1194. http://dx.doi.org/10.1182/blood.v104.11.1194.1194.
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Abstract The salivary glands are often included in the field of irradiation during radiotherapy of head and neck cancer. This can result in severe side-effects that reduces the quality of life of the patient and may even limit the treatment dose. Late damage to the salivary glands is mainly caused by exhaustion of the tissue specific stem cells. Post-irradiation replacement of salivary gland stem cells with donor stem cells may ameliorate radiation-induced complications. Bone marrow-derived stem cells (BMSC) have been shown to be multipotent and thereby able to engraft in many tissues after injury. In this study, we assessed the potential of BMSC to reduce irradiation-induced salivary gland damage. C57BL/6 mice were transplanted with bone marrow from eGFP transgenic animals. After two months the salivary glands of these chimeric mice were locally irradiated with 15 Gy. BMSC were mobilized 10, 30 and/or 60 days after irradiation by s.c. injection of rHu-PEG-G-CSF. Saliva secretion (μl/15 minutes) was measured up to 90 days after irradiation by pilocarpine induction. Hereafter, the glands were extirpated and examined for eGFP-expression. From every individual animal one parotid and one submandibular gland was used to prepare single cell suspensions in order to detect eGFP-positve cells by flow cytometry. The other parotid and submandibular glands were analyzed using confocal laser fluorescence scanning microscopy and light microscopy. G-CSF treatment yielded in an increase of saliva flow for all time points. The optimal time-point for mobilization, however, was 30 days after irradiation as is demonstrated by an improvement of salivary flow from 5 to 30% when compared to radiation alone. FACS analysis showed that up to 10% of the isolated cells were eGFP-positive. Microscopic analysis revealed a similar amount of positive cells and an improved morphology. Immuno-histochemistry using anti-SM-actin antibodies showed the close vicinity of actin and eGFP within the cells, demonstrating the occurence of BMSC derived myoepithelial cells in irradiated salivary glands. Furthermore, using cell-type specific antibodies, the meyoepethilial nature of the eGFP positive was revealed. In conclusion, the results show that BMSC home to severely damaged salivary glands after mobilization. Hence, BMSC mobilization could become a promising modality to ameliorate radiation-induced complications in salivary glands after radiotherapy.
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Haneji, N., H. Hamano, K. Yanagi, and Y. Hayashi. "A new animal model for primary Sjögren's syndrome in NFS/sld mutant mice." Journal of Immunology 153, no. 6 (September 15, 1994): 2769–77. http://dx.doi.org/10.4049/jimmunol.153.6.2769.
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Abstract In this study, we report an established and characterized animal model for primary Sjögren's syndrome in NFS/sld mutant mice bearing an autosomal recessive gene with sublingual gland differentiation arrest. Significant inflammatory changes develop spontaneously in both the salivary and lacrimal glands of NFS/sld mutant mice thymectomized 3 days after birth without any immunization, whereas no significant inflammatory lesions were found in other organs or in nonthymectomized mice. This pathology resembles primary Sjögren's syndrome in humans, which involves the parotid, submandibular salivary, and lacrimal glands. A significantly higher incidence of autoimmune lesions was found in female mice, and the anti-salivary duct autoantibodies were detected in sera from mice with autoimmune lesions but not in control mice. The inflammatory infiltration into the salivary and lacrimal glands consisted mainly of CD3+ and CD4+ T cells, and a lesser proportion of CD8+ T cells and B220+ B cells during the course of disease. When the repertoire of TCR V beta genes transcribed and expressed within the inflammatory infiltrates was analyzed in mice with autoimmune lesions, a considerable preferential use of TCR V beta gene (V beta 8 predominant) was detected in these lesions from the onset of disease. Thus, we can propose a newly established animal model for primary Sjögren's syndrome developing in this mutant strain of mice. Moreover, the predominant patterns of TCR transcript expression in an animal model may be somewhat restricted, suggesting that TCR-based immunotherapy of Sjögren's syndrome is possible.
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Bezman, Dror, Liubov Lemberskiy-Kuzin, Gil Katz, Uzi Merin, and Gabriel Leitner. "Influence of intramammary infection of a single gland in dairy cows on the cow's milk quality." Journal of Dairy Research 82, no. 3 (July 2, 2015): 304–11. http://dx.doi.org/10.1017/s002202991500031x.
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Intramammary infection (IMI), comprises a group of costly diseases affecting dairy animals worldwide. Many dairy parlours are equipped with on-line computerised data acquisition systems designed to detect IMI. However, the data collected is related to the cow level, therefore the contribution of infected glands to the recorded parameters may be over estimated. The present study aimed at evaluating the influence of single gland IMI by different bacteria specieson the cow's overall milk quality. A total of 130 cows were tested 239 times; 79 cows were tested once and the others were examined 2–8 times. All of the analysed data refer to the number of tests performed, taking into account the repeated testing of the same cows. Of the cows tested ~50% were free of infection in all 4 glands and the others were infected in one gland with different coagulase negative staphylococci (CNS), Streptococcus dysgalactiae, or were post infected with Escherichia coli (PIEc), i.e., free of bacterial infection at the time of sampling but 1–2 months after clinical infection by E. coli. Overall, infection with bacteria had significant effects on somatic cell count (SCC) and lactose concentration. Examining each bacterium reveals that the major influence on those parameters was the sharp decrease in lactose in the PIEc and curd firmness in PIEc and Strep. Individual gland milk production decreased ~20% in Strep. dysgalactiae- and ~50% in PIEc-infected glands with respect to glands with no bacterial findings. Significant differences were found in lactose, SCC, rennet clotting time and curd firmness in the milk of infected glands and among those, these parameters were significantly higher in Strep. dysgalactiae and PIEc than in CNS infected cows. The current results using quarter-milking reinforces the importance of accurate IMI detection in relation to economic and welfare factors, and moreover, emphasises the need for technical sensing and constant reporting to the farmer about changes in the milk quality of every animal.
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Billman, Zachary P., Annette M. Seilie, and Sean C. Murphy. "Purification of Plasmodium Sporozoites Enhances Parasite-Specific CD8+T Cell Responses." Infection and Immunity 84, no. 8 (May 23, 2016): 2233–42. http://dx.doi.org/10.1128/iai.01439-15.
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Malaria infection caused byPlasmodiumparasites continues to cause enormous morbidity and mortality in areas where it is endemic, and there is no licensed vaccine capable of inducing sterile protection. Hyperimmunization with attenuated whole sporozoites can induce sterile protective immune responses targeting preerythrocytic antigens. Most animal models of hyperimmunization rely on sporozoites dissected from mosquito salivary glands and injected without further purification. In BALB/c mice, repeated small doses ofP. yoeliisporozoites progressively expand the population of sporozoite-specific CD8+T cells. In this study, large secondary doses of unpurified sporozoites unexpectedly led to contraction of sporozoite-specific CD8+T cell responses in sporozoite-primed mice. While sporozoite-primed CD8+T cells alternatively can be expanded by secondary exposure toListeria monocytogenesexpressing recombinantPlasmodiumantigens, such expansion was potently inhibited by coinjection of large doses of unpurified sporozoites and by uninfected salivary glands alone. Purification of sporozoites away from mosquito salivary gland debris by density gradient centrifugation eliminated salivary gland-associated inhibition. Thus, the inhibitory effect appears to be due to exposure to uninfected mosquito salivary glands rather than sporozoites. To further assess the effect of salivary gland exposure on later sporozoite vaccinations, mice were immunized with uninfected salivary glands from a single mosquito. Compared to naive mice, salivary gland presensitization reduced subsequent liver burdens by 71%. These data show that a component(s) in mosquito salivary glands reduces liver infection, thereby limiting antigen dose and contributing to lower-magnitude T cell responses. These findings suggest that sporozoite immunogenicity studies be performed using purified sporozoites whenever feasible.
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Hughes, Maryanne R., and Darin C. Bennett. "Effects of saline intake, sex, and season on Pekin duck osmoregulatory organ masses and comparison with wild Mallards." Canadian Journal of Zoology 82, no. 1 (January 1, 2004): 30–40. http://dx.doi.org/10.1139/z03-206.
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Osmoregulatory organ masses of freshwater Mallards (Anas platyrhynchos) do not differ between the sexes, but drinking saline induces changes that are sexually disparate in some organs. We examined relative size of organ masses of male and female Pekin ducks (that were domesticated from Mallards) and compared their responses to saline intake with those of Mallards. Organ masses of male and female Mallards do not differ in size. The liver and kidneys are heavier in female Pekin ducks and their digestive tract (except for the proventriculus and duodenum) is longer and heavier; male Pekin ducks have heavier salt glands. Mallards acclimated to saline drinking water have enlarged salt glands but not kidneys, adrenal glands, or Harderian glands, their proventriculus tends to be shorter and lighter, the jejunum longer in males, and the ileum longer and heavier in both sexes. In Pekin ducks that drink saline, the salt and Harderian glands are larger and their kidneys (but not adrenal glands) tend to be larger; the proventriculus is unaffected, but the small intestine is lighter, but not shorter, in females. Body, salt gland, Harderian gland, ventriculus, and duodenum masses vary seasonally in Pekin ducks. Discussion considers the effects of season and sex on relative organ masses and how saline-induced changes in them reflect domestication and may influence salt tolerance.
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Liu, Ying-Juan, Da-Wei Wang, Lixing Sun, Jin-Hua Zhang, and Jian-Xu Zhang. "Flank gland-secreted putative chemosignals pertaining to photoperiod, endocrine states, and sociosexual behavior in golden hamsters." Current Zoology 56, no. 6 (December 1, 2010): 800–812. http://dx.doi.org/10.1093/czoolo/56.6.800.
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Abstract Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Using gas chromatography- mass spectrometry, we detected compounds from the flank glands of males, only eight of which were also produced in females. Based on these chemical data we performed a number of further experiments. By manipulating light we found that males exposed to short-photoperiods developed smaller flank glands than those exposed to long-photoperiods. Six flank gland volatiles reduced in relative abundance, which possibly coded for reproductive status of males of this seasonally breeding hamster species. Through dyadic encounters, we were able to induce the formation of dominant-subordinate relationships and show that two glandular compounds became high in relative abundance and may function as dominance pheromones. Castration eliminated all male-specific compounds resulting from flank glands, but bilateral ovariectomies only affected one compound in females. Once these ovariectomized females were treated with testosterone, their glandular compounds resembled those of males, suggesting these compounds are under the main control of androgen. Two female putative pheromones, tetradecanoic acid and hexadecanoic acid, were used in binary choice tests and were both found to attract males over females. Applying a solution of these pheromone compounds to adult males also suppressed their agonistic behavior.
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Wang, Wenjing, Xupeng Zang, Yonglun Liu, Yunyi Liang, Gengyuan Cai, Zhenfang Wu, and Zicong Li. "Dynamic miRNA Landscape Links Mammary Gland Development to the Regulation of Milk Protein Expression in Mice." Animals 12, no. 6 (March 14, 2022): 727. http://dx.doi.org/10.3390/ani12060727.
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Mammary gland morphology varies considerably between pregnancy and lactation status, e.g., virgin to pregnant and lactation to weaning. Throughout these critical developmental phases, the mammary glands undergo remodeling to accommodate changes in milk production capacity, which is positively correlated with milk protein expression. The purpose of this study was to investigate the microRNA (miRNA) expression profiles in female ICR mice’s mammary glands at the virgin stage (V), day 16 of pregnancy (P16d), day 12 of lactation (L12d), day 1 of forced weaning (FW1d), and day 3 of forced weaning (FW3d), and to identify the miRNAs regulating milk protein gene expression. During the five stages of testing, 852 known miRNAs and 179 novel miRNAs were identified in the mammary glands. Based on their expression patterns, the identified miRNAs were grouped into 12 clusters. The expression pattern of cluster 1 miRNAs was opposite to that of milk protein genes in mammary glands in all five different stages. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that the predicted target genes of cluster 1 miRNAs were related to murine mammary gland development and lactation. Furthermore, fluorescence in situ hybridization (FISH) analysis revealed that the novel-mmu-miR424-5p, which belongs to the cluster 1 miRNAs, was expressed in murine mammary epithelial cells. The dual-luciferase reporter assay revealed that an important milk protein gene—β-casein (CSN2)—was regarded as one of the likely targets for the novel-mmu-miR424-5p. This study analyzed the expression patterns of miRNAs in murine mammary glands throughout five critical developmental stages, and discovered a novel miRNA involved in regulating the expression of CSN2. These findings contribute to an enhanced understanding of the developmental biology of mammary glands, providing guidelines for increasing lactation efficiency and milk quality.
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Scheib, Holger, K. Anne-Isola Nekaris, Johanna Rode-Margono, Lotten Ragnarsson, Kate Baumann, James S. Dobson, Wirdateti Wirdateti, et al. "The Toxicological Intersection between Allergen and Toxin: A Structural Comparison of the Cat Dander Allergenic Protein Fel d1 and the Slow Loris Brachial Gland Secretion Protein." Toxins 12, no. 2 (January 28, 2020): 86. http://dx.doi.org/10.3390/toxins12020086.
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Slow lorises are enigmatic animal that represent the only venomous primate lineage. Their defensive secretions have received little attention. In this study we determined the full length sequence of the protein secreted by their unique brachial glands. The full length sequences displayed homology to the main allergenic protein present in cat dander. We thus compared the molecular features of the slow loris brachial gland protein and the cat dander allergen protein, showing remarkable similarities between them. Thus we postulate that allergenic proteins play a role in the slow loris defensive arsenal. These results shed light on these neglected, novel animals.
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Radice, Glenn L., M. Celeste Ferreira-Cornwell, Stephen D. Robinson, Helen Rayburn, Lewis A. Chodosh, Masatoshi Takeichi, and Richard O. Hynes. "Precocious Mammary Gland Development in P-Cadherin–deficient Mice." Journal of Cell Biology 139, no. 4 (November 17, 1997): 1025–32. http://dx.doi.org/10.1083/jcb.139.4.1025.
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To investigate the functions of P-cadherin in vivo, we have mutated the gene encoding this cell adhesion receptor in mice. In contrast to E- and N-cadherin– deficient mice, mice homozygous for the P-cadherin mutation are viable. Although P-cadherin is expressed at high levels in the placenta, P-cadherin–null females are fertile. P-cadherin expression is localized to the myoepithelial cells surrounding the lumenal epithelial cells of the mammary gland. The role of the myoepithelium as a contractile tissue necessary for milk secretion is clear, but its function in the nonpregnant animal is unknown. The ability of the P-cadherin mutant female to nurse and maintain her litter indicates that the contractile function of the myoepithelium is not dependent on the cell adhesion molecule P-cadherin. The virgin P-cadherin–null females display precocious differentiation of the mammary gland. The alveolar-like buds in virgins resemble the glands of an early pregnant animal morphologically and biochemically (i.e., milk protein synthesis). The P-cadherin mutant mice develop hyperplasia and dysplasia of the mammary epithelium with age. In addition, abnormal lymphocyte infiltration was observed in the mammary glands of the mutant animals. These results indicate that P-cadherin–mediated adhesion and/or signals derived from cell–cell interactions are important determinants in negative growth control in the mammary gland. Furthermore, the loss of P-cadherin from the myoepithelium has uncovered a novel function for this tissue in maintaining the undifferentiated state of the underlying secretory epithelium.