Journal articles: 'Rats – Reproduction – Endocrine aspects'

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Badger, Thomas M., Martin J. J. Ronis, and Reza Hakkak. "Developmental Effects and Health Aspects of Soy Protein Isolate, Casein, and Whey in Male and Female Rats." International Journal of Toxicology 20, no. 3 (May 2001): 165–74. http://dx.doi.org/10.1080/109158101317097755.

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Dietary factors other than the traditional nutrients are found in the so-called functional foods. They are becoming increasingly recognized as potentially important for maintaining good health. Soybeans are rich in such factors thought to help prevent certain chronic diseases. Soy protein isolate (SPI) is one of the three major proteins used in infant formulas sold in the United States, with casein (CAS) and whey (WPH) proteins being the others. We have been studying the health effects of these proteins. Safety concerns have developed over the consumption of soy-based infant formula, partly because of the high circulating levels of the total isoflavones (phytoestrogens) during “critical periods of infant development.” There is a paucity of data on developmental, physiological, neurophysiological, behavioral, metabolic, or molecular effects of soy phytochemicals in humans, especially during pregnancy and infancy. We have studied the effects of CAS, SPI, and WPH in short-term, long-term, and multigenerational studies in rats. Aside from minor differences in body weight gain profiles, CAS-, SPI-or WPH-fed rats did not differ in development, organ weights, in vitro hepatic metabolism of testosterone (T), or reproductive performance. However, some endocrine-related functions differed between rats fed these proteins. We found that SPI accelerated puberty in female rats ( p <.05) and WPH delayed puberty in males and females, as compared with CAS ( p <.05). Gender differences were also found in gonadectomy-induced steroid responses. Male rats had normal serum T levels, but female rats fed SPI had reduced serum 17β-estradiol concentrations and a blunted 17β-estradiol response to ovariectomy, as compared to rats fed CAS or WHP ( p <.05). Female rats fed SPI or WHP or treated with genistein had reduced incidence of chemically induced mammary cancers ( p <.05) compared to CAS controls, with WHP reducing tumor incidence by as much as 50%, findings that replicate previous results from our laboratory. Together, these results suggest gender-specific differences in development and certain endocrine responses among rats fed diets composed of a single protein source such as those used in infant formulas. Whether similar developmental effects occur in human infants is unknown, but unlikely because (1) most infants do not consume such diets throughout life as these rats did, and (2) no such effects have been reported in millions of American infants fed infant formula containing these proteins. The long-term health consequence implications of early diet exposure to SPI and WPH, such as reduced breast cancer incidence, are likely to be very positive.

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Gerardin, Daniela C. C., Renata C. Piffer, Patrícia C. Garcia, Estefânia G. Moreira, and Oduvaldo C. M. Pereira. "Effects of maternal exposure to an aromatase inhibitor on sexual behaviour and neurochemical and endocrine aspects of adult male rat." Reproduction, Fertility and Development 20, no. 5 (2008): 557. http://dx.doi.org/10.1071/rd07213.

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The present study examined the effects of letrozole exposure during brain sexual differentiation on endocrine, behavioural and neurochemical parameters in male rat descendants. Pregnant female rats received 1 mg kg–1 day–1 letrozole or vehicle by oral gavage on gestational Days 21 and 22. Exposure to letrozole reduced anogenital distance in males on postnatal Day (PND) 22. At adulthood (PND 75), plasma testosterone levels and hypothalamic dopaminergic activity were increased, but sexual competence was impaired, because fewer successful sexual behaviours (mount, intromission and principally ejaculation) were observed. The impairment of reproductive function by prenatal exposure to an aromatase inhibitor reinforces the importance of adequate oestrogenic activity during perinatal sexual differentiation for complete masculinisation of the hypothalamus.

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Valentim, Jean Kaique, Janaína Palermo Mendes, Bruna Barreto Przybulinski, Felipe Cardoso Serpa, Deivid Kelly Barbosa, Vivian Aparecida Rios Castilho, and Rita Therezinha Rolim Pietramale. "Fatores Nutricionais Aplicados à Reprodução de Ruminantes." UNICIÊNCIAS 23, no. 2 (December 4, 2019): 77. http://dx.doi.org/10.17921/1415-5141.2019v23n2p77-82.

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Os animais de produção estão sendo modificados através de um intenso melhoramento genético, buscando intensificar seu desempenho para atender a demanda mundial em quesitos de alimentação. Essa maximização de desempenho demanda um acréscimo nutricional, e este por sua vez pode afetar as funções reprodutivas. Vários estudos mostram que a reprodução pode ser comprometida se as necessidades nutricionais dos animais não forem atendidas. Esta demanda nutricional afeta diretamente a função dos órgãos reprodutivos e o funcionamento do sistema endócrino, podendo interferir na taxa de fertilidade destes animais. A nutrição tem influência na fertilidade, diretamente por meio do fornecimento de nutrientes específicos, que são necessários para os processos de desenvolvimento do folículo, de ovulação, de maturação oocitária, de fertilização, de sobrevivência embrionária e o estabelecimento da gestação e, indiretamente, atuando sobre as concentrações circulantes dos hormônios e outros metabólitos sensíveis aos nutrientes que são requeridos para o sucesso destes processos. O objetivo do presente trabalho é obter uma revisão de literatura atualizada sobre o contexto recente da influência de fatores nutricionais sobre os aspectos reprodutivos de animais ruminantes. Palavras-chave: Nutrição. Metabolismo. Fertilidade. Ruminantes. AbstractThe farm animals are being modified through an intensive genetic improvement seeking to increase their performance to meet the global demand on power issues. This performance maximization demands an extra nutritional and this in turn can affect the reproductive functions. Several studies show that the reproduction can be compromised if the animal’s nutritional needs are met. This nutritional demand directly affects the function of the reproductive organs and the functioning of the endocrine system and may interfere with fertility rate of these animals. Nutrition affects fertility, directly through the provision of specific nutrients that are required for the processes of development of follicle maturation, ovulation, oocyte , fertilization, embryo survival and the establishment of pregnancy; and, indirectly, acting on circulating concentrations of hormones and other metabolites sensitive to nutrients that are required for the success of these processes. The goal of this work was to obtain an updated literature review with recent studies related to nutritional aspects involved in the ruminant animals reproduction. Keywords: Nutrition. Metabolism. Fertility. Ruminants.

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Nurdiana, Nurdiana, Pradnyawati Chania, Rifzi Nurvitasari, Azmiatun Nisa, Styan Wahyu Diana, Evalina Izzatur Rochmah, Elly Mayangsari, et al. "The Effect of Soy Milk on Mounting Latency, Mounting Frequency, and Reproductive Development in Male Wistar Rats (Rattus Norvegicus)." Open Access Macedonian Journal of Medical Sciences 9, B (August 17, 2021): 670–78. http://dx.doi.org/10.3889/oamjms.2021.6416.

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AIM: This research aims to examine the effects of soy milk on mounting latency (ML), mounting frequency (MF), estrogen levels, androgen-binding protein (ABP) expression, and spermatogenesis in male rats (Rattus norvegicus). METHODS: Twenty-four male wistar rats (Rattus norvegicus) aged 4 weeks were divided into four groups. Control group (given a normal diet), P1; P2; P3 (given the normal diet and soy milk powder at doses of 7.1; 14.2; 21.3 g/KgBW/day, respectively) for 6 weeks. Observation of ML and MF were performed at 9 weeks 5 days of age, and rat surgery was performed at 10 weeks of age. Analysis of estrogen hormone levels was conducted by enzyme-linked immunosorbent assay (ELISA), ABP staining was using immunohistochemistry method, testicular spermatogenesis was observed using histopathological methods, and observation of spermatozoa was performed under the microscope. RESULTS: The results showed no significant reduction of ML and MF, estrogen levels, and ABP expression (p ≤ 0.256; 0.865; 0.959, respectively) in male rat, but there was a significant decrease in the number, morphology, motility of spermatozoa, and testicular histophatology, (p ≤ 0.000, 0.003, 0.008, 0.000, respectively). CONCLUSION: The administrassion of soy milk in various doses (7.1;14.2;21.3 g/KgBW/day) in male Wistar rats (Rattus norvegicus) had showed significantly difference on histopathological evaluation using Johnson’s scoring system, sperm quantity and quality, while on mounting latency and frequency, estrogen levels, and ABP expressions did not show significantly difference between groups. That describe of isoflavone in soy milk can affect several aspects related to male endocrine and reproductive development.

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Klowden, Marc J. "Endocrine aspects of mosquito reproduction." Archives of Insect Biochemistry and Physiology 35, no. 4 (1997): 491–512. http://dx.doi.org/10.1002/(sici)1520-6327(1997)35:4<491::aid-arch10>3.0.co;2-5.

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Seliukova, N. Yu, K. V. Misyura, and G. V. Storozhenko. "EXPERIMENTAL MODELS OF FETOPLACEENTAL INSUFFICIENCY IN ANIMALS (LITERATURE REVIEW AND OWN OBSERVATIONS)." Актуальні проблеми сучасної медицини: Вісник Української медичної стоматологічної академії 20, no. 4 (December 30, 2020): 225–31. http://dx.doi.org/10.31718/2077-1096.20.4.225.

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This literature review is devoted to experimental models of placental disorders in animals. Today, our knowledge of the structure and function of the placenta during pregnancy is remaining limited. The use of new technologies and imaging methods in animals that can provide safe monitoring of the growth and function of the placenta in vivo requires preclinical studies and trials in appropriately developed animal models that can be easily translated into a clinical setting. All this, of course, requires the use of test animals for modelling placental pathologies. The review considers the positive and negative aspects of various animals and methods of modelling the pathological conditions during pregnancy. In the experiment, models of fetoplacental insufficiency are very often used, arising from oxidative stress and activation of free radical oxidation. To simulate the experimental fetoplacental insufficiency caused by histotoxic hypoxia, the xenobiotic tetrachloromethane is used. Women of very young and mature reproductive age have a high risk of fetoplacental insufficiency. It is not known exactly how placental insufficiency in mothers will affect the sexual development of pubertal offspring. That is why we conducted a comprehensive experimental study on this issue at the base of V. Danilevsky Institute of Endocrine Pathology Problems, NAMS of Ukraine. To solve this problem, our institute has developed and proposed a new pharmaceutical composition that should not only contribute to the correction of placental insufficiency, but also has a certain prophylactic value for maintaining reproductive potential in adulthood. The study was carried out on Wistar rats of two age groups. We modelled experimental fetoplacental insufficiency and then corrected it with this pharmaceutical composition. Our study made it possible to establish that fetoplacental insufficiency has a different effect on the formation of the reproductive system in male and female rats in puberty. Prophylactic adding of the composition to the food for pregnant female rats with modelled placental insufficiency leads to the decrease in reproductive diseases of their offspring in puberty. Research on animal models provides important insight into the molecular and functional mechanisms underlying fetoplacental insufficiency and intrauterine growth retardation, as it enables to carry out studies, which are not possible in pregnant women.

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Tomatis, Veronica, Christian Battipaglia, and Alessandro D. Genazzani. "Thyroid, Adrenal, PRL Impairments and Ovarian Function." Endocrines 2, no. 3 (July 27, 2021): 212–25. http://dx.doi.org/10.3390/endocrines2030021.

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Endocrine axes (prolactin, thyroid and adrenal axes) directly and indirectly modulate and drive human female central functions, mainly behavior and reproduction. Though having distinct abilities, they greatly act both at peripheral as well as at neuroendocrine levels, so as to participate in the control of reproduction. Any event that changes these balanced activities produces specific peripheral signals that induce abnormal functions centrally, thus triggering menstrual disorders such as oligomenorrhea or amenorrhea. It is clear that the knowledge of the relationships that exist between the different endocrine axes becomes essential for the choice of therapeutical approach. This review aims to focus on the main aspects of the physiopathology of the endocrine diseases that might be at the basis of that interference with female reproductive capacity.

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Chen, Hao, Zhaoping Liu, Xiaopeng Zhang, Xudong Jia, Qian Li, Qing Su, and Wei Wang. "Assessment of synergistic thyroid disrupting effects of a mixture of EDCs in ovariectomized rats using factorial analysis and dose addition." Toxicology Research 5, no. 6 (2016): 1585–93. http://dx.doi.org/10.1039/c6tx00193a.

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Phillips-Farfán, Bryan V., and Alonso Fernández-Guasti. "Endocrine, neural and pharmacological aspects of sexual satiety in male rats." Neuroscience & Biobehavioral Reviews 33, no. 3 (March 2009): 442–55. http://dx.doi.org/10.1016/j.neubiorev.2008.11.003.

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van der Ven, Leo T. M., Ton van de Kuil, Pim E. G. Leonards, Wout Slob, Hellmuth Lilienthal, Sabina Litens, Maria Herlin, et al. "Endocrine effects of hexabromocyclododecane (HBCD) in a one-generation reproduction study in Wistar rats." Toxicology Letters 185, no. 1 (February 2009): 51–62. http://dx.doi.org/10.1016/j.toxlet.2008.12.003.

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Chetrite, Gérard S., and Bruno Fève. "Preface to special issue on Peripheral and Central Control of Human Reproduction: Endocrine Aspects – Part 1." Hormone Molecular Biology and Clinical Investigation 24, no. 1 (January 1, 2015): 1–3. http://dx.doi.org/10.1515/hmbci-2015-0059.

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Chetrite, Gérard S., and Bruno Fève. "Preface to special issue on Peripheral and Central Control of Human Reproduction: Endocrine Aspects – Part 2." Hormone Molecular Biology and Clinical Investigation 25, no. 1 (January 1, 2016): 1–3. http://dx.doi.org/10.1515/hmbci-2016-0011.

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De Rensis, Fabio, Giorgio Morini, Irina Garcia-Ispierto, and Fernando López-Gatius. "To What Extent Does Photoperiod Affect Cattle Reproduction? Clinical Perspectives of Melatonin Administration – A Review." Annals of Animal Science 20, no. 3 (July 1, 2020): 797–809. http://dx.doi.org/10.2478/aoas-2020-0012.

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AbstractThe seasonality of reproduction in most mammals is dictated by photoperiod, temperature and nutrition. Melatonin, mainly synthesized in the pineal gland, is generally accepted as the active mediator of photoperiod responses including reproduction. While non-pregnant heifers and cows show continuous sexual activity and are therefore not seasonal breeders, it has been suggested that photo-periodicity may influence the appearance of puberty in heifers and the onset of parturition. Further, the light/dark ratio may influence endocrine patterns of gestation and a shorter light period correlates with the incidence of twin pregnancies. This review considers specific aspects of the effects of photoperiod and melatonin on reproduction in dairy cattle and discusses the clinical applications of melatonin.

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Ortega, Hugo H., Belkis E. Marelli, Florencia Rey, Ayelen N. Amweg, Pablo U. Díaz, Matías L. Stangaferro, and Natalia R. Salvetti. "Molecular aspects of bovine cystic ovarian disease pathogenesis." REPRODUCTION 149, no. 6 (June 2015): R251—R264. http://dx.doi.org/10.1530/rep-14-0618.

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Cystic ovarian disease (COD) is one of the main causes of reproductive failure in cattle and causes severe economic loss to the dairy farm industry because it increases both days open in the post partum period and replacement rates due to infertility. This disease is the consequence of the failure of a mature follicle to ovulate at the time of ovulation in the estrous cycle. This review examines the evidence for the role of altered steroid and gonadotropin signaling systems and the proliferation/apoptosis balance in the ovary with cystic structures. This evidence suggests that changes in the expression of ovarian molecular components associated with these cellular mechanisms could play a fundamental role in the pathogenesis of COD. The evidence also shows that gonadotropin receptor expression in bovine cystic follicles is altered, which suggests that changes in the signaling system of gonadotropins could play a fundamental role in the pathogenesis of conditions characterized by altered ovulation, such as COD. Ovaries from animals with COD exhibit a disrupted steroid receptor pattern with modifications in the expression of coregulatory proteins. These changes in the pathways of endocrine action would trigger the changes in proliferation and apoptosis underlying the aberrant persistence of follicular cysts.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/149/6/R251/suppl/DC1.

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Santos, Jadson Pinheiro, Simone de Jesus Melo Almeida, Claryce Cunha Costa, Erick Cristofore Guimarães, Erivânia Gomes Teixeira, and Raimunda Nonata Fortes Carvalho-Neta. "Reproductive aspects of freshwater fishes exposed to pesticide-contamined environments: A systematic review." Revista Brasileira de Gestão Ambiental e Sustentabilidade 8, no. 19 (2021): 1155–68. http://dx.doi.org/10.21438/rbgas(2021)081935.

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Fish are the predominant group of vertebrates in aquatic environments, and they are directly affected by the presence of contaminants in water bodies, which undergo changes in the structure and function of communities and dynamics of the populations. The aim of the present study was to conduct a systematic review of studies that analyze the reproductive aspects of freshwater teleosts in environments contaminated by pesticides. A systematic search for scientific articles was carried out from 2000 to 2019 using the "Web of Science" database, using the descriptors "fish reproduction", "contamination", "toxicology", "ecotoxicity" and "biomonitoring", combined with the use of boolean operators "AND" and "OR". The content analysis was performed based on the titles and the summary, with a first screening. Then, 98 articles were read in full, with 40 being selected. 24 species of fish were recorded, with a predominance of Danio rerio (17.5%). Insecticides were present in 78% of the studies, mainly Endosulfan (35%) and Cypermethrin (13%). Reproductive endocrine disorders were the most reported pathways of action (57.5%). The effects of pesticides on the reproduction of freshwater teleosts are evident, requiring studies on structural changes in gonads and a decrease in the quality of gametes.

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Ingaramo, Paola I., Jorgelina Varayoud, María M. Milesi, Marlise Guerrero Schimpf, Mónica Muñoz-de-Toro, and Enrique H. Luque. "Effects of neonatal exposure to a glyphosate-based herbicide on female rat reproduction." Reproduction 152, no. 5 (November 2016): 403–15. http://dx.doi.org/10.1530/rep-16-0171.

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In this study, we investigated whether neonatal exposure to a glyphosate-based herbicide (GBH) alters the reproductive performance and the molecular mechanisms involved in the decidualization process in adult rats. Newborn female rats received vehicle or 2 mg/kg/day of a GBH on postnatal days (PND) 1, 3, 5 and 7. On PND90, the rats were mated to evaluate (i) the reproductive performance on gestational day (GD) 19 and (ii) the ovarian steroid levels, uterine morphology, endometrial cell proliferation, apoptosis and cell cycle regulators, and endocrine pathways that regulate uterine decidualization (steroid receptors/COUP-TFII/Bmp2/Hoxa10) at the implantation sites (IS) on GD9. The GBH-exposed group showed a significant increase in the number of resorption sites on GD19, associated with an altered decidualization response. In fact, on GD9, the GBH-treated rats showed morphological changes at the IS, associated with a decreased expression of estrogen and progesterone receptors, a downregulation of COUP-TFII (Nr2f2) and Bmp2 mRNA and an increased expression of HOXA10 and the proliferation marker Ki67(Mki67) at the IS. We concluded that alterations in endometrial decidualization might be the mechanism of GBH-induced post-implantation embryo loss.

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Schuenemann, G. M., J. L. Edwards, F. M. Hopkins, N. R. Rohrbach, H. S. Adair, F. N. Scenna, J. C. Waller, J. W. Oliver, A. M. Saxton, and F. N. Schrick. "Fertility aspects in yearling beef bulls grazing endophyte-infected tall fescue pastures." Reproduction, Fertility and Development 17, no. 4 (2005): 479. http://dx.doi.org/10.1071/rd05005.

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During a 2-year study, yearling beef bulls were used to determine the effects of grazing on endophyte-infected tall fescue on endocrine profiles, semen quality and fertilisation potential. Bulls were allotted to graze tall fescue pastures infected with Neotyphodium coenophialum (E+; n = 20 per year) or Jesup/MaxQTM (Pennington Seed, Atlanta, GA, USA; NTE; n = 10 per year). Bulls were grouped by scrotal circumference (SC), bodyweight (BW), breed composites and age to graze tall fescue pastures from mid-November until the end of June (within each year). Blood samples, BW, SC and rectal temperatures (RT) were collected every 14 days. Semen was collected from bulls every 60 days by electroejaculation and evaluated for motility and morphology. The developmental competence of oocytes fertilised in vitro with semen from respective treatments was determined. Bulls grazing E+ pastures had decreased BW gain (P < 0.01), increased overall RT (P < 0.01) and decreased prolactin (P < 0.01) compared with animals grazing NTE pastures. Neither percentage of normal sperm morphology nor motility differed between bulls grazed on the two pasture types. Semen from E+ bulls demonstrated decreased cleavage rates (P = 0.02) compared with semen from NTE bulls. However, development of cleaved embryos to the eight-cell and blastocyst stages did not differ between the two groups. In conclusion, semen from bulls grazing E+ tall fescue resulted in decreased cleavage rates in vitro, which may lower reproductive performance owing to reduced fertilisation ability.

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Ungerfeld, R., M. Forsberg, and E. Rubianes. "Overview of the response of anoestrous ewes to the ram effect." Reproduction, Fertility and Development 16, no. 4 (2004): 479. http://dx.doi.org/10.1071/rd04039.

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The present review summarises knowledge of the reproductive response of anoestrous ewes to the introduction of rams – in other words, the ram effect. The ovarian and endocrine response, the factors that determine whether ewes will respond or not (associated with both the stimulus and the receptivity of the ewes) and some aspects of practical management are discussed. Information on the use of the ram effect to stimulate post-partum, prepubertal and cyclic ewes is also given. New insights are provided on ovarian response patterns, including recently collected information on luteal responses. The existence of delayed ovulation (5–7 days after the introduction of the rams) followed by luteal phases of normal or short length, luteal cysts and luteinised follicles is reported after scanning the ovaries with ultrasound. Endocrine parameters for depth of anoestrus, such as LH pulsatility and FSH concentrations, and how the concentrations of these hormones should be considered are discussed. Particular attention is paid to the observation of spontaneous, higher LH pulsatility and higher FSH concentrations in anoestrous ewes that respond to rams with luteal phases than in those that fail to respond. The use of progestogen priming and single progestogen administration and the possible advantages for synchronisation of oestrus are also discussed. Other factors that should be considered before the ram effect is applied, such as the strength of the stimulus and some practical considerations, are also included.

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Mikolić, Anja, and Irena Brčić Karačonji. "Imidacloprid as reproductive toxicant and endocrine disruptor: investigations in laboratory animals." Archives of Industrial Hygiene and Toxicology 69, no. 2 (June 1, 2018): 103–8. http://dx.doi.org/10.2478/aiht-2018-69-3144.

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AbstractImidacloprid, a neonicotinoid insecticide, has been used worldwide due to its selective toxicity for insects. Its residues may enter the food chain, which is why it is important to investigate the potential adverse effects of imidacloprid exposure. This review summarises current knowledge of the reproductive toxicity and disruptive endocrine effects of imidacloprid in laboratory animals. Investigations, conducted mostly on laboratory rats, have shown adverse effects of imidacloprid on the reproductive ability in both parental and offspring generation as well as on the development of the offspring. Like many pesticides, imidacloprid may also act as endocrine disrupting chemical (EDC). It may disrupt the metabolic homeostasis, contribute to obesity, and disrupt steroidogenesis by inhibiting cytochrome P450 (CYP) enzyme activities. All these adverse effects of imidacloprid may pose a serious risk for reproduction and development with long-term consequences in adulthood.

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Masubuchi, Yoshiko, Masami Tanaka, Toshio Kumai, Taiichiro Ohno, Minoru Watanabe, Mitsuko Suetsuna, and Masanao Hirai. "Endocrine pharmacology of reproduction (Report 41): Influence of uterine extracts from intact and indomethacin-treated rats on ovarian steroidogenesis." Japanese Journal of Pharmacology 40 (1986): 74. http://dx.doi.org/10.1016/s0021-5198(19)58977-6.

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Manservisi, Fabiana, Kalpana Gopalakrishnan, Eva Tibaldi, Albana Hysi, Manuela Iezzi, Luca Lambertini, Susan Teitelbaum, Jia Chen, and Fiorella Belpoggi. "Effect of maternal exposure to endocrine disrupting chemicals on reproduction and mammary gland development in female Sprague-Dawley rats." Reproductive Toxicology 54 (July 2015): 110–19. http://dx.doi.org/10.1016/j.reprotox.2014.12.013.

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Whitlock, BK, JA Daniel, RR Wilborn, TH Elsasser, JA Carroll, and JL Sartin. "Comparative Aspects of the Endotoxin- and Cytokine-Induced Endocrine Cascade Influencing Neuroendocrine Control of Growth and Reproduction in Farm Animals." Reproduction in Domestic Animals 43 (July 2008): 317–23. http://dx.doi.org/10.1111/j.1439-0531.2008.01180.x.

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Tetel, Marc J., Diane C. Celentano, and Jeffrey D. Blaustein. "Intraneuronal Convergence of Tactile and Hormonal Stimuli Associated with Female Reproduction in Rats." Journal of Neuroendocrinology 6, no. 2 (April 1994): 211–16. http://dx.doi.org/10.1111/j.1365-2826.1994.tb00574.x.

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Guo, Hai-Xiang, Bao Yuan, Meng-Ting Su, Yi Zheng, Jin-Yu Zhang, Dong-Xu Han, Hao-Qi Wang, Yi-Jie Huang, Hao Jiang, and Jia-Bao Zhang. "Identification of Circular RNAs in the Anterior Pituitary in Rats Treated with GnRH." Animals 11, no. 9 (August 31, 2021): 2557. http://dx.doi.org/10.3390/ani11092557.

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The pituitary gland, an important endocrine organ, can secrete a variety of reproductive hormones under the action of hypothalamus-secreted gonadotropin-releasing hormone (GnRH) and plays important roles in animal reproduction. Circular RNAs (circRNAs) are a class of RNA molecules with stable covalently closed circular structures. CircRNAs are equipped with miRNA response elements (MREs), which can regulate the expression of target genes by competitively binding miRNAs. However, whether the expression levels of circRNAs in the pituitary gland change under the action of GnRH and whether such changes can further affect the secretion of reproductive hormones are still unclear. In this study, we performed RNA sequencing (RNA-Seq) of GnRH-treated rats to identify differentially expressed circRNAs. The results revealed 1433 related circRNAs, 14 of which were differentially expressed. In addition, we randomly selected five differentially expressed circRNAs and tested their relative expression levels by RT-qPCR, the results of which were consistent with the RNA sequencing results. Finally, we predicted targeted relationships between the differentially expressed circRNAs and FSHb-LHb-associated miRNAs. In all, a total of 14 circRNAs were identified that may act on the secretion and regulation of reproductive hormones in GnRH-treated rats. Our expression profiles of circRNAs in the anterior pituitaries of rats treated with GnRH can provide insights into the roles of circRNAs in mammalian development and reproduction.

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Freud, A., and U. A. Sod-moriah. "Changes in the Endocrine System Controlling Reproduction in Mature Female Rats Neonatally Exposed to A low Dose of Gamma Irradiation." Endocrine Research 15, no. 3 (January 1989): 323–38. http://dx.doi.org/10.3109/07435808909042744.

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Masubuchi, Yoshiko, Taiichiro Ohno, Toshio Kumai, Masami Tanaka, Minoru Watanabe, and Masanao Hirai. "Endocrine Pharmacology of Reproduction (Report 48) : Abnormal testicular and adrenal steroidogenesis and their response to tropic hormones in hypercholesterolemic rats." Japanese Journal of Pharmacology 43 (1987): 151. http://dx.doi.org/10.1016/s0021-5198(19)58259-2.

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Toufexis, D. J., D. Kyriazis, and B. Woodside. "Chronic Neuropeptide Y Y5 Receptor Stimulation Suppresses Reproduction in Virgin Female and Lactating Rats." Journal of Neuroendocrinology 14, no. 6 (May 29, 2002): 492–97. http://dx.doi.org/10.1046/j.1365-2826.2002.00805.x.

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Roselli, C. E., E. Cross, H. K. Poonyagariyagorn, and H. L. Stadelman. "Role of aromatization in anticipatory and consummatory aspects of sexual behavior in male rats." Hormones and Behavior 44, no. 2 (August 2003): 146–51. http://dx.doi.org/10.1016/s0018-506x(03)00123-5.

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Meier, Ursula, and Axel M. Gressner. "Endocrine Regulation of Energy Metabolism: Review of Pathobiochemical and Clinical Chemical Aspects of Leptin, Ghrelin, Adiponectin, and Resistin." Clinical Chemistry 50, no. 9 (September 1, 2004): 1511–25. http://dx.doi.org/10.1373/clinchem.2004.032482.

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Abstract Background: Recent studies point to the adipose tissue as a highly active endocrine organ secreting a range of hormones. Leptin, ghrelin, adiponectin, and resistin are considered to take part in the regulation of energy metabolism. Approach: This review summarizes recent knowledge on leptin and its receptor and on ghrelin, adiponectin, and resistin, and emphasizes their roles in pathobiochemistry and clinical chemistry. Content: Leptin, adiponectin, and resistin are produced by the adipose tissue. The protein leptin, a satiety hormone, regulates appetite and energy balance of the body. Adiponectin could suppress the development of atherosclerosis and liver fibrosis and might play a role as an antiinflammatory hormone. Increased resistin concentrations might cause insulin resistance and thus could link obesity with type II diabetes. Ghrelin is produced in the stomach. In addition to its role in long-term regulation of energy metabolism, it is involved in the short-term regulation of feeding. These hormones have important roles in energy homeostasis, glucose and lipid metabolism, reproduction, cardiovascular function, and immunity. They directly influence other organ systems, including the brain, liver, and skeletal muscle, and are significantly regulated by nutritional status. This newly discovered secretory function has extended the biological relevance of adipose tissue, which is no longer considered as only an energy storage site. Summary: The functional roles, structures, synthesis, analytical aspects, and clinical significance of leptin, ghrelin, adiponectin, and resistin are summarized.

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Rojas, Joselyn, Mervin Chávez-Castillo, Luis Carlos Olivar, María Calvo, José Mejías, Milagros Rojas, Jessenia Morillo, and Valmore Bermúdez. "Physiologic Course of Female Reproductive Function: A Molecular Look into the Prologue of Life." Journal of Pregnancy 2015 (2015): 1–21. http://dx.doi.org/10.1155/2015/715735.

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The genetic, endocrine, and metabolic mechanisms underlying female reproduction are numerous and sophisticated, displaying complex functional evolution throughout a woman’s lifetime. This vital course may be systematized in three subsequent stages: prenatal development of ovaries and germ cells up untilin uteroarrest of follicular growth and the ensuing interim suspension of gonadal function; onset of reproductive maturity through puberty, with reinitiation of both gonadal and adrenal activity; and adult functionality of the ovarian cycle which permits ovulation, a key event in female fertility, and dictates concurrent modifications in the endometrium and other ovarian hormone-sensitive tissues. Indeed, the ultimate goal of this physiologic progression is to achieve ovulation and offer an adequate environment for the installation of gestation, the consummation of female fertility. Strict regulation of these processes is important, as disruptions at any point in this evolution may equate a myriad of endocrine-metabolic disturbances for women and adverse consequences on offspring both during pregnancy and postpartum. This review offers a summary of pivotal aspects concerning the physiologic course of female reproductive function.

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Dziendzikowska, K., M. Oczkowski, M. Stachoń, J. Wilczak, T. Królikowski, R. Mruk, J. Gromadzka-Ostrowska, et al. "Inhalation of diesel engine exhaust from combustion of 1st generation biodiesel fuel (B20) affects endocrine regulation of reproduction in male rats." Toxicology Letters 258 (September 2016): S182. http://dx.doi.org/10.1016/j.toxlet.2016.06.1675.

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Comninos, Alexander N., and Waljit S. Dhillo. "Emerging Roles of Kisspeptin in Sexual and Emotional Brain Processing." Neuroendocrinology 106, no. 2 (August 31, 2017): 195–202. http://dx.doi.org/10.1159/000481137.

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The emergence of kisspeptin as a crucial regulator of the hypothalamo-pituitary-gonadal (HPG) axis over the last 14 years has answered many questions as to the control of reproductive hormone secretion from the hypothalamus. More recently, the role of kisspeptin outside the HPG axis has received increasing attention in the hope of delineating the pathways linking various sensory and social behaviours to reproduction. These studies, in a range of species from zebrafish to humans, have identified a role for kisspeptin in behavioural networks related to reproduction including olfaction, audition, fear, anxiety, mood, and sexual arousal. The available evidence suggests that extrahypothalamic kisspeptin signalling encourages positive aspects of emotional and sexual brain processing in a presumed drive towards reproduction and ultimately maintenance of the species at a population level. In this review, we examine these studies, which collectively propose that kisspeptin may integrate sexual and emotional brain processing with the control of the HPG axis.

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Zoltán, Kun Imre, Kun Ildikó, and Kolcsár Melinda. "Current aspects of polycystic ovary syndrome I: definition, pathophysiology, clinical manifestations, diagnosis and complications." Bulletin of Medical Sciences 91, no. 1 (July 1, 2018): 5–18. http://dx.doi.org/10.2478/orvtudert-2018-0011.

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Abstract Polycystic ovary syndrome (PCOS) is the most frequent endocrine disease among women with childbearing potential, the best-known cause of hirsutism, with a hypothesized prevalence of 8-22%. The first part of the paper discusses the conceptional evolution of the syndrome, from its description in 1935 by Stein and Leventhal till today. It describes the changes in the criteria systems, emphasizing that the Rotterdam criteria, proposed in 2003 by the European Society for Human Reproduction and Embryology/American Society for Reproductive Medicine, are still valid today. This system basically differs from earlier (1990) NIH-criteria in one aspect: it introduced two newer phenotypes, one without hyperandrogenism and the other with ovulatory cycles, so it distinguishes 4 phenotypes. The etiology and pathogenesis of PCOS is heterogeneous, multifactorial, poorly understood. We present the 3 leading hypotheses (1 - hypothalamo-hypophyseal disturbances, 2 – primary enzyme disorders in ovarian, or ovarian/adrenal steroidogenesis, resulting primarily in hyperactivity of 17alpha-hydroxylase/17,20-lyase, 3 – insulin resistance-hyperinsulinism and other metabolic dysfunctions). We emphasize the role of genetically determined hyperandrogenism, that of insulin resistance-hyperinsulinism and the importance of reinforcing each other. Subsequently, the aggravating aspects of the frequently associated metabolic syndrome are discussed, and then the effects of the mentioned pathological processes on the endocrine and other organ structures participating in the regulation of sexual functions. We stress the hypothetical role of perinatal and pubertal androgen exposition in the pathogenesis of PCOS. The mechanisms of anovulation and those of the endometrial lesions are discussed, too. The clinical manifestations, the paraclinical and laboratory examinations, the positive and differential diagnosis and the complications are also presented. We intend to deal with the therapeutic aspects of PCOS in an upcoming paper.

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Fukushima, S., and A. Freyberger. "Simple, rapid assays for conventional definite testing of endocrine disruptor hazard: Summary and recommendations." Pure and Applied Chemistry 75, no. 11-12 (January 1, 2003): 2479–82. http://dx.doi.org/10.1351/pac200375112479.

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Study protocols for the characterization of endocrine active compounds presented in Workshop 4 included the enhanced Organization for Economic Cooperation and Development (OECD) test guideline (TG) 407, the medium-term rat liver and rat multi-organ carcinogenicity assays, and an enhanced one-generation reproduction study. The outcome of rat studies on flutamide and ethinylestradiol indicated that these strongly active compounds can readily be detected even with a low animal number using the enhanced OECD TG 407. Both newly added (such as male accessory sex organ weights, histology of pituitary, vagina and male mammary gland) and already included parameters contributed to the detection of endocrine effects. Thorough evaluation of the results of 20 studies conducted with 10 compounds thought to interfere with the endocrine system by different mechanisms will identify the most appropriate enhancements to the current OECD TG 407. Medium-term rat liver and rat multi-organ carcinogenicity assays are well recognized in the International Conferences on Harmonization for Pharmaceutical Chemicals. They have been successfully used to detect carcinogenic and modifying potentials of new chemicals within a relatively short time and can be applied to endocrine active compounds. Dose-response studies on nonylphenol, bisphenol A, and styrene using the rat liver carcinogenicity assay did not reveal effects of any of these compounds on the development of preneoplastic lesions in rat liver. The enhanced one-generation reproduction study protocol included treatment of pregnant female rats from gestation day 0 through to lactation day 21, and examination of all offspring. Half of the animals were necropsied at weaning, the remaining animals were examined for vaginal opening, preputial separation, estrous cyclicity, and sperm characteristics and were necropsied at adulthood. In a pilot study ethinylestradiol inhibited maternal fertility at dose levels similar to those effective in the uterotrophic assay. It is recommended to rapidly evaluate the conducted enhanced OECD TG 407 studies and to enhance the current OECD TG 407 appropriately. Further compounds with different mechanisms of action should be studied in the one-generation reproduction study to further investigate the usefulness of this protocol. The established medium-term carcinogenicity assays can be used to study carcinogenic potential rapidly. Use of female animals and inclusion of carcinogens targeting at breast and uterus should be considered in order to explore further the predictibility of this model.

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Fernandez-Novo, Aitor, Sonia S. Pérez-Garnelo, Arantxa Villagrá, Natividad Pérez-Villalobos, and Susana Astiz. "The Effect of Stress on Reproduction and Reproductive Technologies in Beef Cattle—A Review." Animals 10, no. 11 (November 11, 2020): 2096. http://dx.doi.org/10.3390/ani10112096.

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Researchers have contributed by increasing our understanding of the factors affecting reproduction in beef, mainly physical health and nutrition aspects, which have been main concerns during decades. Animal welfare is of outmost relevance in all animal production systems and it is strongly associated to stress. Stress responses involve endocrine, paracrine and neural systems and the consequences of this stress on the reproductive efficiency of specifically, beef cattle and bulls, need to be highlighted. We, therefore, describe the fundamentals of stress and its quantification, focusing in beef herds, reviewing the highly valuable pieces of research, already implemented in this field. We examine major factors (stressors) contributing to stress in beef cattle and their effects on the animals, their reproductive performance and the success of reproductive biotechnologies. We include terms such as acclimatization, acclimation or temperament, very relevant in beef systems. We examine specifically the management stress due to handling, social environment and hierarchy or weaning effects; nutritional stress; and thermal stress (not only heat stress) and also review the influence of these stressors on reproductive performance and effectiveness of reproductive biotechnologies in beef herds. A final message on the attention that should be devoted to these factors is highlighted.

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Fregly, MJ, and NE Rowland. "Hormonal and Neural Mechanisms of Sodium Appetite." Physiology 1, no. 2 (April 1, 1986): 51–54. http://dx.doi.org/10.1152/physiologyonline.1986.1.2.51.

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A strong appetite for salt seems to be a normal link in the complex mechanisms that serve to maintain a normal sodium content of the organism. Experiments with rats have helped to unravel many aspects of the endocrine mechanisms that are involved in regulating sodium balance and salt appetite, but more work is needed to understand the mechanisms that induce salt appetite in different species.

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Ali, Badreldin H., Intisar Al-Lawati, Sumyia Beegam, Amal Ziada, Suhail Al salam, Abderrahim Nemmar, and Gerald Blunden. "Effect of Hibiscus sabdariffa and its Anthocyanins on Some Reproductive Aspects in Rats." Natural Product Communications 7, no. 1 (January 2012): 1934578X1200700. http://dx.doi.org/10.1177/1934578x1200700115.

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An aqueous extract of Hibiscus sabdariffa L. is a common beverage in many parts of the world. Reports on its effect on reproduction are conflicting, with anecdotal evidence that the plant is an aphrodisiac, while others report that it is estrogenic, and adversely affects spermatogenesis in rats. We have studied the effect of different concentrations of aqueous extracts of H. sabdariffa calyces (10%, 15% and 20%) used as drinking water for 10 consecutive weeks, and its anthocyanins (50, 100, 200 mg/kg for 5 days, orally) on the weight and histology of the testis, and on some biochemical constituents in testicular homogenates, in addition to the plasma concentrations of testosterone, luteinizing hormone and estradiol. The possible presence of an estrogenic effect of the extract and anthocyanins on the uteri of immature female rats was also tested. Neither the H. sabdariffa extract nor the anthocyanins significantly altered either testicular weight and histology, or uterus weight. Plasma concentrations of the three hormones studied, the testicular concentrations of protein, reduced glutathione and total cholesterol, and superoxide dismutase activity were all insignificantly affected by either the extract or the anthocyanins, except for a slight, but statistically significant, decrease in testicular protein concentration caused by the 15% aqueous extract when compared with controls. These results suggest that H. sabdariffa exerts no adverse effect on the male reproductive system. Consumption of H. sabdariffa aqueous extract inhibited the growth of the rats compared with the controls.

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Van der Ven, Leo T. M., Ton Van de Kuil, Aart Verhoef, Cynthia M. Verwer, Hellmuth Lilienthal, Pim E. G. Leonards, Ute M. D. Schauer, et al. "Endocrine effects of tetrabromobisphenol-A (TBBPA) in Wistar rats as tested in a one-generation reproduction study and a subacute toxicity study." Toxicology 245, no. 1-2 (March 2008): 76–89. http://dx.doi.org/10.1016/j.tox.2007.12.009.

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Kim, Joshua, Sheila J. Semaan, Donald K. Clifton, Robert A. Steiner, Sangeeta Dhamija, and Alexander S. Kauffman. "Regulation of Kiss1 Expression by Sex Steroids in the Amygdala of the Rat and Mouse." Endocrinology 152, no. 5 (March 1, 2011): 2020–30. http://dx.doi.org/10.1210/en.2010-1498.

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Kisspeptin (encoded by the Kiss1 gene) is an important regulator of reproduction. In rodents, Kiss1 is expressed in two hypothalamic regions, the arcuate nucleus and anteroventral periventricular/ periventricular continuum, where it is regulated by sex steroids. However, the distribution, regulation, and functional significance of neural kisspeptin outside of the hypothalamus have not been studied and are poorly understood. Here, we report the expression of Kiss1 in the amygdala, predominantly in the medial nucleus of the amygdala (MeA), a region implicated in social and emotional behaviors as well as various aspects of reproduction. In gonadally intact rats and mice, Kiss1-expressing neurons were identified in the MeA of both sexes, with higher Kiss1 expression levels in adult males than females in diestrus. In rats, Kiss1 expression in the MeA changed as a function of the estrous cycle, with highest levels at proestrus. Next, we tested whether Kiss1 in the MeA is regulated by the circulating sex steroid milieu. Kiss1 levels in the MeA were low in gonadectomized mice and rats of both sexes, and treatment with either testosterone or estradiol amplified Kiss1 expression in this region. Testosterone's inductive effect on Kiss1 expression in the MeA likely occurs via estrogen receptor-dependent pathways, not through the androgen receptor, because dihydrotestosterone (a nonaromatizable androgen) did not affect MeA Kiss1 levels. Thus, in rodents, Kiss1 is expressed and regulated by sex steroids in the MeA of both sexes and may play a role in modulating reproduction or brain functions that extend beyond reproduction.

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Koreneva, E., N. Philimonova, N. Brechka, E. Chistyakova, N. Smolyenko, I. Belkina, and N. Karpenko. "Modeling of chronic prostatitis. Abacterial prostatitis in the aspects of reproduction of experimental hypofertility (review)." Problems of Endocrine Pathology 67, no. 1 (March 4, 2019): 104–15. http://dx.doi.org/10.21856/j-pep.2019.1.13.

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There is a problem of modeling of prostatitis in animals despite of the progress at the creation of prostatic protectors capable of correcting hypofertility. In this regard, modeling prostate gland pathology, monitoring its development and finding out factors causing a decrease in the generative function in prostatitis are topical issues. In this review, the important role of experimental modeling of prostatitis have been shown, the etiology, pathogenesis and clinical manifestations of prostatitis, the epidemiology of reproductive impairment in conditions of abacterial inflammatory process of the prostate gland have been reviewed, and data about methods of prostatitis modelling in laboratory animals. Such modeling of chronic abacterial prostatitis in rats has been reviewed: by rectal administration of dimexide and turpentine; by cryotrauma; piercing (traumatic) prostatitis; prostatitis after hypokinetic stress; autoimmune prostatitis; acute aseptic inflammation of the prostate gland; chronic prostatitis by applying metaxylene; as well as experimental models of prostatitis associated with hormonal effects. Summarizing the literature data, the authors conclude that the experimental modeling of chronic prostatitis is an issue of importance not only for the study of the course of this common disease, but also for the development of new methods and measures for the treatment of prostatitis and reproductive health disorders that occur on the background or accompanied by inflammation.

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Kumbhar, Umesh B., Bhushan Kumar Charpe, and Sarbjeet Kumar. "Bovine Embryonic Mortality with Special Reference to Mineral Deficiency, Heat Stress and Endocrine Factors: A Review." International Journal of Bio-resource and Stress Management 12, no. 1 (February 28, 2021): 047–58. http://dx.doi.org/10.23910/1.2021.2139a.

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Embryonic Mortality is the major cause of reproductive and economic loss in cattle and Buffaloes. Embryonic Mortality is more common during the early than the late embryonic period, i.e., from day 8th to 16th at the hatching of blastocysts and initiation of elongation and commencement of implantation without affecting cycle lengths. Early embryonic mortality is a major source of embryonic and economic loss with mortality rate up to 40%. Embryonic mortality is also reported due to mineral deficiency and heat stress in cattle and buffaloes. Physical modifications of animal environment, nutritional management with Antioxidant, trace minerals and genetic development of breeds that are less sensitive to heat stress should be best solution. Embryonic death occurs at the time of maternal recognition of pregnancy, probably related to a failure of the Interferon tau (IFNι) secretory mechanism along with progesterone deficiency and luteal insufficiency. Recent research, both in terms of physiological mechanisms and pharmacological treatments has mostly focused on the period of maternal recognition of pregnancy or the anti-luteolytic effect. hCG/ GnRH /Progesterone supplementation have shown positive results. Supplementation of interferon as anti-luteolytic agent and supplementing Omega-3 has shown encouraging results. Ovarian examination, Animal history, blood/milk progesterone levels, PAG test and ultrasound appear to be the only practical tool presently available for diagnosis of embryonic mortality. This present review article is covering all the aspects of embryonic mortality with special reference totrace minerals, heat stress, hormonal impact and interferon tau.

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Ferasyi, Teuku R., P. Hugh R. Barrett, Dominique Blache, and Graeme B. Martin. "Modeling the Male Reproductive Endocrine Axis: Potential Role for a Delay Mechanism in the Inhibitory Action of Gonadal Steroids on GnRH Pulse Frequency." Endocrinology 157, no. 5 (February 24, 2016): 2080–92. http://dx.doi.org/10.1210/en.2015-1913.

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Abstract We developed a compartmental model so we could test mechanistic concepts in the control of the male reproductive endocrine axis. Using SAAM II computer software and a bank of experimental data from male sheep, we began by modeling GnRH-LH feed-forward and LH-T feedback. A key assumption was that the primary control signal comes from a hypothetical neural network (the PULSAR) that emits a digital (pulsatile) signal of variable frequency that drives GnRH secretion in square wave-like pulses. This model produced endocrine profiles that matched experimental observations for the testis-intact animal and for changes in GnRH pulse frequency after castration and T replacement. In the second stage of the model development, we introduced a delay in the negative feedback caused by the aromatization of T to estradiol at the brain level, a concept supported by empirical observations. The simulations showed how changes in the process of aromatization could affect the response of the pulsatile signal to inhibition by steroid feedback. The sensitivity of the PULSAR to estradiol was a critical factor, but the most striking observation was the effect of time delays. With longer delays, there was a reduction in the rate of aromatization and therefore a decrease in local estradiol concentrations, and the outcome was multiple-pulse events in the secretion of GnRH/LH, reflecting experimental observations. In conclusion, our model successfully emulates the GnRH-LH-T-GnRH loop, accommodates a pivotal role for central aromatization in negative feedback, and suggests that time delays in negative feedback are an important aspect of the control of GnRH pulse frequency.

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Fusani, Leonida, Daniele Della Seta, Francesco Dessì-Fulgheri, and Francesca Farabollini. "Altered reproductive success in rat pairs after environmental-like exposure to xenoestrogen." Proceedings of the Royal Society B: Biological Sciences 274, no. 1618 (April 24, 2007): 1631–36. http://dx.doi.org/10.1098/rspb.2007.0064.

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Endocrine-disrupting compounds (EDCs) have the capacity of altering the normal function of the endocrine system. EDCs have shown dramatic effects on the reproductive biology of aquatic wildlife and may affect human reproduction as well. Studies on EDCs in mammalian species have often investigated the effects of short-term, high doses on male and female reproductive physiology. However, it is difficult to predict from such studies the effects of EDC on populations that are exposed to very low doses throughout their life via contaminated food and water. We studied the effects of EDC on mammalian reproduction with an environmental-like protocol where the endpoint is the reproductive success of exposed pairs. We focused on a subclass of EDC, the xenoestrogens, which mimic the action of natural oestrogen hormones. Male and female rats were exposed to low doses of the pure oestrogen, ethynyloestradiol, during development, by oral administration to their mothers during pregnancy and lactation, and to them until puberty. We evaluated the effects of the exposure on development and reproductive physiology of individuals, and on fertility and fecundity of pairs in which both members had been exposed to the same treatment. We found that low doses caused major reproductive deficits in the experimental animals. Very low, environmentally relevant doses did not have evident effects on exposed animals; however, the fecundity of exposed pairs was substantially altered. Environmentally relevant doses of xenoestrogens which have no evident physiological effects can alter the reproductive success of exposed pairs in natural populations.

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Khomyn, N. M., A. R. Mysak, S. V. Tsisinska, V. V. Pritsak, N. V. Nazaruk, and Yu M. Lenjo. "Some aspects of the occurrence and development of chronic aseptic pododermatitis in highly pregnant cows." Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 22, no. 99 (October 28, 2020): 45–52. http://dx.doi.org/10.32718/nvlvet9907.

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Pododermatitis in tall cows that occur on the background of secondary osteodystrophy can lead to significant economic losses, consisting of forced culling of animals, reduced milk yield, reproductive function and not enough receiving of calves. Therefore, the question of studying the peculiarities of origin and development, in particular chronic aseptic pododermatitis in these animals is quite actual. It is defined that with the same type of highly concentrated feeding, hypodynamics and insufficient insolation in the organism of highly pregnant cows, the process of assimilation of feed minerals is disrupted (develops, as is known, for dysfunction of the endocrine glands due to prolonged ketosis), which is appeared by resorption of the hoof bone, low rates of mass-volume extraction analysis of bone biopsy and testifies a systemic violation of mineral metabolism in animals and is confirmed by biochemical parameters, in particular, the concentration in the hoof horn of individual macro-and trace elements, as well as biophysical parameters of the epidermis of the hooves. Thus, the concentration of Calcium in the hoof horn is 16.8 % lower than in clinically healthy animals, Sulfur – by 20.3 %, Copper – by 16.2, Zinc – by 15.0, Cobalt – by 13.0 with increasing concentration of sulfhydryl groups by 34.3 % and moisture, respectively – by 5.5 %, which causes a decrease in the density and hardness of the epidermis of the hooves by 5.4 % and 19.0 %, respectively, and contributes to the deterioration of the quality of the hooves of highly pregnant cows. Such changes lead to deformation of the hooves, violation of the uniform load on their soles and the development of aseptic inflammation of the skin base of the hooves of a chronic nature, because the process of metabolic disorders occurs over a long period of time.

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Fu, Houju, Yuanqiao He, Ying Gao, Yicun Man, Wukun Liu, and Hua Hao. "Acupuncture on the Endometrial Morphology, the Serum Estradiol and Progesterone Levels, and the Expression of Endometrial Leukaemia-inhibitor Factor and Osteopontin in Rats." Evidence-Based Complementary and Alternative Medicine 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/606514.

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Although it is well known that acupuncture has beneficial effects on a variety of medical conditions especially in pain relief, nausea, and vomiting, it remains controversial whether it has positive impact on the female reproduction. The present study aimed to evaluate whether the following endometrial receptivity factors: the endometrial morphology, the hormone concentrations, and the protein expression of endometrial leukaemia-inhibitory factor (LIF) and osteopontin (OPN) could be improved by the acupuncture in clomiphene citrate(CC)-induced rat model during implantation period. Results showed that, compared with the CC group, glandular development advanced, the serum estradiol levels decreased significantly, and the glandular area and endometrial LIF and OPN expression were significantly higher in acupuncture group. There were no significant differences in serum progesterone levels, endometrial thickness, and stromal area between groups. These results suggest that acupuncture can improve certain aspects of endometrial receptivity in CC-induced rat model during implantation period, which might result in endometrial state better to female reproduction.

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Molenda-Figueira, Heather A., Casey A. Williams, Andreana L. Griffin, Eric M. Rutledge, Jeffrey D. Blaustein, and Marc J. Tetel. "Nuclear receptor coactivators function in estrogen receptor- and progestin receptor-dependent aspects of sexual behavior in female rats." Hormones and Behavior 50, no. 3 (September 2006): 383–92. http://dx.doi.org/10.1016/j.yhbeh.2006.04.005.

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Kuzmina, I. U., and M. V. Zhulikova. "PATHOGENETIC ASPECTS OF THE INTERMITTENT OF THE DEVELOPMENT OF THE POLYCYSTIC OVARY SYNDROME WITH PROLONGED COLD INFLUENCES IN THE EXPERIMENT." Problems of Endocrine Pathology 66, no. 4 (December 3, 2018): 44–51. http://dx.doi.org/10.21856/j-pep.2018.4.05.

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The aim of the research was to study the effect of intermittent cold effects (ICE) on the experimentally induced polycystic ovary syndrome (PCOS) in female rats to prevent the development of polycystic ovaries and elaboration the pathogenesis of its development. Simulation of PCOS was performed by subcutaneous injection of dehydroepiandrosterone acetate (DHEA) in rats for 25 days. A ICE was carried out by daily keeping the animals for 4 hours in a chamber in which the light regime and a temperature of + 4 °C were maintained. As a result of the experiments, it has been proved that after intracellular adaptive-compensatory reactions are activated in the ovarian tissue, which helps prevent the development of PCOS. In addition, ICE leads to an increase in the level of adipocytokines (adiponectin and leptin), which can indirectly affect the secretion of reproduction hormones and inhibit the development of cystic changes in the ovary. Stimulation of adaptive physiological reactions against the background of ICE blocks the development of signs of PCOS in rats.

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Yoshikawa, Tomoko, Michael Sellix, Pinar Pezuk, and Michael Menaker. "Timing of the Ovarian Circadian Clock Is Regulated by Gonadotropins." Endocrinology 150, no. 9 (June 11, 2009): 4338–47. http://dx.doi.org/10.1210/en.2008-1280.

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Abstract The timing of ovulation is critically important to the success of reproduction. Current thinking attributes the timing of ovulation to LH secretion by the pituitary, itself timed by signals from the hypothalamus. The discovery of an internal circadian timer in the ovary raises the possibility that ovulation is in fact timed by an interaction between clocks in the hypothalamus/pituitary and those in the ovary. We asked whether ovarian clocks were influenced by signals from the brain and pituitary. Ovaries of Period1-luciferase transgenic rats display circadian rhythms in vitro. To determine whether the phase of these rhythms is set by neural or endocrine signals, we surgically denervated or heterotopically transplanted ovaries with or without encapsulation in dialysis membranes. Animals’ light-dark cycles were phase advanced or delayed 6 h, and the resetting of the ovarian clock was tracked by culturing ovaries at intervals over the next 12 d. Resetting trajectories of control, surgically denervated, and encapsulated ovaries were similar, demonstrating that endocrine signals are sufficient to transmit phase information to the ovary. We next evaluated LH and FSH as potential endocrine signals. Using the phase of Per1-luc expression in granulosa cell cultures, we demonstrated that both of these pituitary hormones caused large phase shifts when applied to the cultured cells. We hypothesize that the ovarian circadian clock is entrained by hormonal signals from the pituitary and that ovulation depends, in part, on the phase in the ovarian circadian cycle at which these signals occur.

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Handgraaf, Sandra, and Jacques Philippe. "The Role of Sexual Hormones on the Enteroinsular Axis." Endocrine Reviews 40, no. 4 (May 10, 2019): 1152–62. http://dx.doi.org/10.1210/er.2019-00004.

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AbstractSex steroid estrogens, androgens, and progesterone, produced by the gonads, which have long been considered as endocrine glands, are implicated in sexual differentiation, puberty, and reproduction. However, the impact of sex hormones goes beyond these effects through their role on energy metabolism. Indeed, sex hormones are important physiological regulators of glucose homeostasis and, in particular, of the enteroinsular axis. In this review, we describe the roles of estrogens, androgens, and progesterone on glucose homeostasis through their effects on pancreatic α- and β-cells, as well as on enteroendocrine L-cells, and their implications in hormonal biosynthesis and secretion. The analysis of their mechanisms of action with the dissection of the receptors implicated in the several protective effects could provide some new aspects of the fine-tuning of hormonal secretion under the influence of the sex. This knowledge paves the way to the understanding of transgender physiology and new potential therapeutics in the field of type 2 diabetes.

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van der Veen, Daan R., Sjaak J. Riede, Paul D. Heideman, Michaela Hau, Vincent van der Vinne, and Roelof A. Hut. "Flexible clock systems: adjusting the temporal programme." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1734 (October 9, 2017): 20160254. http://dx.doi.org/10.1098/rstb.2016.0254.

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Under natural conditions, many aspects of the abiotic and biotic environment vary with time of day, season or even era, while these conditions are typically kept constant in laboratory settings. The timing information contained within the environment serves as critical timing cues for the internal biological timing system, but how this system drives daily rhythms in behaviour and physiology may also depend on the internal state of the animal. The disparity between timing of these cues in natural and laboratory conditions can result in substantial differences in the scheduling of behaviour and physiology under these conditions. In nature, temporal coordination of biological processes is critical to maximize fitness because they optimize the balance between reproduction, foraging and predation risk. Here we focus on the role of peripheral circadian clocks, and the rhythms that they drive, in enabling adaptive phenotypes. We discuss how reproduction, endocrine activity and metabolism interact with peripheral clocks, and outline the complex phenotypes arising from changes in this system. We conclude that peripheral timing is critical to adaptive plasticity of circadian organization in the field, and that we must abandon standard laboratory conditions to understand the mechanisms that underlie this plasticity which maximizes fitness under natural conditions. This article is part of the themed issue ‘Wild clocks: integrating chronobiology and ecology to understand timekeeping in free-living animals’.

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Journal articles on the topic 'Rats – Reproduction – Endocrine aspects'

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