Journal articles: 'Bovine retina'

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Saari, John C., Robert J. Champer, Mary Ann Asson-Batres, Gregory G. Garwin, Jing Huang, John W. Crabb, and Ann H. Milam. "Characterization and localization of an aldehyde dehydrogenase to amacrine cells of bovine retina." Visual Neuroscience 12, no. 2 (March 1995): 263–72. http://dx.doi.org/10.1017/s095252380000794x.

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AbstractAn enzyme of bovine retina that catalyzes oxidation of retinaldehyde to retinoic acid was purified to homogeneity and a monoclonal antibody (mAb H-4) was generated. MAb H-4 recognized a single component (Mr = 55,000) in extracts of bovine retina and other bovine tissues. The antibody showed no cross-reactivity with extracts of rat, monkey, or human retinas. A 2067 bp cDNA was selected from a retina cDNA expression library using mAb H-4. The cDNA hybridized with a similarly sized, moderately abundant mRNA prepared from bovine retina. Nucleotide sequence analysis indicated that the cDNA contained a single open reading frame encoding 501 amino acids that have 88% sequence identity with the amino-acid sequence of human hepatic Class 1 aldehyde dehydrogenase. Amino-acid sequence analysis of purified enzyme demonstrated that the cDNA encodes the isolated enzyme. MAb H-4 specifically labeled the somata and processes of a subset of amacrine cells in bovine retinal sections. Labeled amacrine somata were located on both sides of the inner plexiform layer, and their processes ramified into two laminae within the inner plexiform layer. The inner radial processes of Müller (glial) cells were weakly reactive with mAb H-4. Weak immunostaining of amacrine cells was found in monkey retina with mAb H-4, but no signal was detected in rat or human retina. The results provide further evidence for metabolism and function of retinoids within cells of the inner retina and define a novel class of retinal amacrine cells.

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Sitaramayya, Ari, Lorraine Lombardi, and Alexander Margulis. "Influence of dopamine on cyclic nucleotide enzymes in bovine retinal membrane fractions." Visual Neuroscience 10, no. 6 (November 1993): 991–96. http://dx.doi.org/10.1017/s0952523800010099.

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AbstractDopamine is a major neurotransmitter and neuromodulator in vertebrate retina. Although its pharmacological and physiological actions are well understood, the biochemical mechanisms of its signal transduction are less clear. Acting via D1 receptors, dopamine was shown to increase cyclic AMP levels in intact retina and to activate adenylate cyclase in retinal homogenates. The action via activation of D2 receptors is controversial: it was reported to decrease cyclic AMP levels in intact retina but inhibition of cyclase could not be demonstrated in retinal homogenates; also it was reported to activate rod outer segment cyclic GMP phosphodiesterase in vitro but did not decrease cyclic GMP levels in aspartate-treated retinas. We made an attempt to fractionate bovine retinal membranes and to investigate the effects of dopamine, via Dl and D2 receptors, on the synthesis and hydrolysis of cyclic AMP and cyclic GMP. Activation of cyclic AMP synthesis was noted in all fractions, but no effects were evident on cyclic nucleotide hydrolysis or cyclic GMP synthesis in any fraction. Also, D2 agonist did not inhibit cyclic AMP synthesis. These observations suggest that D2 receptors may not be directly coupled to cyclic nucleotide metabolizing enzymes in bovine retina.

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Yan, Qi, E. Helene Sage, and Anita E. Hendrickson. "SPARC Is Expressed by Ganglion Cells and Astrocytes in Bovine Retina." Journal of Histochemistry & Cytochemistry 46, no. 1 (January 1998): 3–10. http://dx.doi.org/10.1177/002215549804600102.

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SPARC (secreted protein, acidic and rich in cysteine)/osteonectin is a matricellular, counteradhesive glycoprotein that disrupts cell-matrix interactions, interacts with growth factors and components of extracellular matrix, and modulates the cell cycle, but appears to subserve only minor structural roles. SPARC is expressed in a variety of tissues during embryogenesis and remodeling and is believed to regulate vascular morphogenesis and cellular differentiation. Although usually limited in normal adult tissues, SPARC is expressed at significant levels in the adult central nervous system. Using a monoclonal antibody against bovine bone osteonectin, we have determined the localization of SPARC in newborn (3-day-old) and adult (4–8-year-old) normal bovine retinas. SPARC was present in the soma of ganglion cells and strong reactivity was found in ganglion cell axons. Muller cells displayed no immunoreactivity, but SPARC was present in retinal astrocytes that were identified by the astrocyte marker glial fibrillary acidic protein (GFAP). Newborn calf retina showed a staining pattern similar to that of adult retina but exhibited significantly reduced levels of SPARC. Minimal levels of SPARC protein were also detected in some capillaries of the inner retina of both newborn and adult animals, whereas large vessels were negative. The presence of SPARC in the retina was confirmed by Western blotting of retinal extracts. These data indicate that SPARC originating from both neurons and glia of the inner retina may be an important modulator of retinal angiogenesis. The increased expression of SPARC in adult relative to newborn retinal tissue also indicates that SPARC has an ongoing role in the maintainance of retinal functions.

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Koscielniak, A., M. Serafin, M. Duda, T. Oles, A. Zadlo, A. Broniec, O. Berdeaux, et al. "Oxidation-Induced Increase In Photoreactivity of Bovine Retinal Lipid Extract." Cell Biochemistry and Biophysics 75, no. 3-4 (November 2, 2017): 443–54. http://dx.doi.org/10.1007/s12013-017-0832-3.

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Abstract The mammalian retina contains a high level of polyunsaturated fatty acids, including docosahexaenoic acid (22:6) (DHA), which are highly susceptible to oxidation. It has been shown that one of the products of DHA oxidation—carboxyethylpyrrole (CEP), generated in situ, causes modifications of retinal proteins and induces inflammation response in the outer retina. These contributing factors may play a role in the development of age-related macular degeneration (AMD). It is also possible that some of the lipid oxidation products are photoreactive, and upon irradiation with blue light may generate reactive oxygen species. Therefore, in this work we analysed oxidation-induced changes in photoreactivity of lipids extracted from bovine neural retinas. Lipid composition of bovine neural retinas closely resembles that of human retinas making the bovine tissue a convenient model for studying the photoreactivity and potential phototoxicity of oxidized human retinal lipids. Lipid composition of bovine neural retinas Folch’ extracts (BRex) was determined by gas chromatography (GC) and liquid chromatography coupled to an electrospray ionization source-mass spectrometer (LC-ESI-MS) analysis. Liposomes prepared from BRex, equilibrated with air, were oxidized in the dark at 37 °C for up to 400 h. The photoreactivity of BRex at different stages of oxidation was studied by EPR-oximetry and EPR-spin trapping. Photogeneration of singlet oxygen (1O2, 1Δg) by BRex was measured using time-resolved detection of the characteristic phosphorescence at 1270 nm. To establish contribution of lipid components to the analysed photoreactivity of Folch’ extract of bovine retinas, a mixture of selected synthetic lipids in percent by weight (w/w %) ratio resembling that of the BRex has been also studied. Folch’s extraction of bovine neural retinas was very susceptible to oxidation despite the presence of powerful endogenous antioxidants such as α-tocopherol and zeaxanthin. Non-oxidized and oxidized BRex photogenerated singlet oxygen with moderate quantum yield. Blue-light induced generation of superoxide anion by Folch’ extract of bovine neural retinas strongly depended on the oxidation time. The observed photoreactivity of the studied extract gradually increased during its in vitro oxidation.

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Rodriguez, K. A., and A. T. Tsin. "Retinyl esters in the vertebrate neuroretina." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 256, no. 1 (January 1, 1989): R255—R258. http://dx.doi.org/10.1152/ajpregu.1989.256.1.r255.

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High-performance liquid chromatography (HPLC) was employed to measure retinyl esters in the vertebrate retina. Both retina and retinal pigment epithelium (RPE) from frog, chicken, and bovine eyes were studied. In comparison to the RPE, the retina possessed a significant level of 11-cis and all trans retinyl palmitate. Using a sensitive radioassay, we also detected the presence of retinyl ester hydrolase (REH) activity in homogenates prepared from both retina and RPE. The rate of retinyl ester hydrolysis in these retinas was sufficiently high to supply retinal chromophores for the metabolic renewal and for the regeneration of visual pigments. In comparison to retinyl esters in the RPE, retinyl esters in the retina are located much closer to the sites of visual pigment synthesis and regeneration. Hence it is possible that these retinyl esters play a more important role in the visual cycle than those in the RPE.

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Milam, Ann H., Daniel E. Possin, Jing Huang, Robert N. Fariss, John G. Flannery, and John C. Saari. "Characterization of aldehyde dehydrogenase-positive amacrine cells restricted in distribution to the dorsal retina." Visual Neuroscience 14, no. 3 (May 1997): 601–8. http://dx.doi.org/10.1017/s0952523800012256.

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AbstractA class 1 aldehyde dehydrogenase (ALDH) catalyzes oxidation of retinaldehyde to retinoic acid in bovine retina. We used immunocytochemistry and in situ hybridization to localize this enzyme in adult and fetal bovine retinas. Specific ALDH immunoreactivity was present in the cytoplasm of wide-field amacrine cells restricted in distribution to the dorsal part of the adult retina. The somata diameters ranged from ∼8 μ to ∼15 μ, and the cells increased in density from ∼125 cells/mm2 near the horizontal meridian to ∼425 cells/mm2 in the superior far periphery. The ALDH-positive cells had somata on both sides of the inner plexiform layer (IPL) and processes in two IPL strata. The majority of ALDH-positive cells were unreactive with antibodies against known amacrine cell enzymes and neurotransmitters, including GABA and glycine. The ALDH-positive amacrine cells also did not react with anti-cellular retinoic acid-binding protein, which was present in a subset of GABA-positive amacrine cells. In flat-mounted retinas processed by in situ hybridization, the larger ALDH-positive amacrine cells tended to be more heavily labeled. In addition to amacrine cells, Müller cell processes in the inner retina were weakly immunoreactive for ALDH; however, these glial cells did not contain ALDH mRNA. The pattern of ALDH expression in fetal bovine retinas was documented by immunocytochemistry. No ALDH reactivity was found before 5.5 months; for the remainder of the fetal period, ALDH immunoreactivity was present in amacrine cells similar to those in adult retina. The ALDH-positive amacrine cells in bovine retina are novel, being limited in distribution to the dorsal retina and unlabeled with other amacrine cell-specific markers. Identification of ALDH in amacrine cells provides additional evidence that cells of the inner retina are involved in retinoid metabolism.

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Das, S. R., N. Bhardwaj, H. Kjeldbye, and P. Gouras. "Muller cells of chicken retina synthesize 11-cis-retinol." Biochemical Journal 285, no. 3 (August 1, 1992): 907–13. http://dx.doi.org/10.1042/bj2850907.

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The amounts of endogenous retinyl palmitate, retinol and retinaldehyde were measured in the neural retina and retinal pigment epithelium (RPE) of predominantly cone (chicken), rod (rat) and more mixed (cat, human) retinae. The ratio of 11-cis to all-trans isomers of retinyl palmitate and retinol in the neural retina and the RPE increases progressively with the increase in diurnality of the species from rat to chicken. The membrane fractions of both chicken and bovine RPE enzymically isomerize all-trans retinol to 11-cis-retinol. Chicken neural retina membranes enzymically form 11-cis-retinol and all-trans-retinyl palmitate from all-trans-retinol. Light and electron microscopy revealed no contamination of chicken neural retina by RPE. Muller cells from chicken retina were isolated, cultured and characterized by immunocytochemical localization of cellular retinaldehyde-binding protein. Cultured chicken Muller cells form all-trans-retinyl palmitate, 11-cis-retinol and 11-cis-retinyl palmitate from all-trans-retinol and release most of the 11-cis-retinol into the medium. The results indicate that chicken neural retina and Muller cells in particular synthesize 11-cis-retinoids from all-trans-retinol.

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Dejda, Agnieszka, Izabela Matczak, and Wojciech A. Gorczyca. "p19 detected in the rat retina and pineal gland is a guanylyl cyclase-activating protein (GCAP)." Acta Biochimica Polonica 49, no. 4 (December 31, 2002): 899–905. http://dx.doi.org/10.18388/abp.2002_3749.

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The Ca(2+)-dependent activation of retina-specific guanylyl cyclase (retGC) is mediated by guanylyl cyclase-activating proteins (GCAPs). Here we report for the first time detection of a 19 kDa protein (p19) with GCAP properties in extracts of rat retina and pineal gland. Both extracts stimulate synthesis of cGMP in rod outer segment (ROS) membranes at low (30 nM) but not at high (1 microM) concentrations of Ca(2+). At low Ca(2+), immunoaffinity purified p19 activates guanylyl cyclase(s) in bovine ROS and rat retinal membranes. Moreover, p19 is recognized by antibodies against bovine GCAP1 and, similarly to other GCAPs, exhibits a Ca(2+)-dependent electrophoretic mobility shift.

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Smith, J. D., J. J. Greenlee, A. N. Hamir, J. A. Richt, and M. H. West Greenlee. "Retinal Function and Morphology Are Altered in Cattle Infected with the Prion Disease Transmissible Mink Encephalopathy." Veterinary Pathology 46, no. 5 (May 9, 2009): 810–16. http://dx.doi.org/10.1354/vp.08-vp-0206-w-fl.

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Transmissible spongiform encephalopathies (TSEs) are a group of diseases that result in progressive and invariably fatal neurologic disease in both animals and humans. TSEs are characterized by the accumulation of an abnormal protease-resistant form of the prion protein in the central nervous system. Transmission of infectious TSEs is believed to occur via ingestion of prion protein–contaminated material. This material is also involved in the transmission of bovine spongiform encephalopathy (“mad cow disease”) to humans, which resulted in the variant form of Creutzfeldt-Jakob disease. Abnormal prion protein has been reported in the retina of TSE-affected cattle, but despite these observations, the specific effect of abnormal prion protein on retinal morphology and function has not been assessed. The objective of this study was to identify and characterize potential functional and morphologic abnormalities in the retinas of cattle infected with a bovine-adapted isolate of transmissible mink encephalopathy. We used electroretinography and immunohistochemistry to examine retinas from 10 noninoculated and 5 transmissible mink encephalopathy–inoculated adult Holstein steers. Here we show altered retinal function, as evidenced by prolonged implicit time of the electroretinogram b-wave, in transmissible mink encephalopathy–infected cattle before the onset of clinical illness. We also demonstrate disruption of rod bipolar cell synaptic terminals, indicated by decreased immunoreactivity for the alpha isoform of protein kinase C and vesicular glutamate transporter 1, and activation of Müller glia, as evidenced by increased glial fibrillary acidic protein and glutamine synthetase expression, in the retinas of these cattle at the time of euthanasia due to clinical deterioration. This is the first study to identify both functional and morphologic alterations in the retinas of TSE-infected cattle. Our results support future efforts to focus on the retina for the development of new strategies for the diagnosis of TSEs.

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MARGULIS, ALEXANDER, NIKOLAY POZDNYAKOV, LOAN DANG, and ARI SITARAMAYYA. "Soluble guanylate cyclase and nitric oxide synthase in synaptosomal fractions of bovine retina." Visual Neuroscience 15, no. 5 (May 1998): 867–73. http://dx.doi.org/10.1017/s0952523898155098.

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Cyclic GMP has been shown in recent years to directly activate ion channels in bipolar and ganglion cells, and to indirectly regulate coupling between horizontal cells, and between bipolar and amacrine cells. In all of these cases, the effects of cyclic GMP are mimicked by nitric oxide. An increase in calcium concentration stimulates the production of nitric oxide by neuronal and endothelial forms of nitric oxide synthase, which in turn activates soluble guanylate cyclases, enhancing the synthesis of cyclic GMP. Though some effects of nitric oxide do not involve cyclic GMP, the nitric oxide-cyclic GMP cascade is well recognized as a signaling mechanism in brain and other tissues. The widespread occurrence of nitric oxide/cyclic GMP-regulated ion channel activity in retinal neurons raises the possibility that nitric-oxide-sensitive soluble guanylate cyclases play an important role in cell–cell communication, and possibly, synaptic transmission. Immunohistochemical studies have indicated the presence of soluble guanylate cyclase in retinal synaptic layers, but such studies are not suitable for determination of the density or quantitative subcellular distribution of the enzyme. Microanalytical methods involving microdissection of frozen retina also showed the presence of cyclase activity in retinal plexiform layers but these methods did not permit distinction between nitric oxide-sensitive and insensitive cyclases. In this study, we fractionated retinal homogenate into the cytosolic and synaptosomal fractions and investigated the specific activity and distribution of soluble guanylate cyclase and nitric oxide synthase. The results show that both enzymes are present in the synaptosomal fractions derived from inner and outer plexiform layers. The synaptosomal fraction derived from inner retina was highly enriched in cyclase activity. Nitric oxide synthase activity was also higher in the inner than outer retinal synaptosomal fraction. The results suggest that the nitric oxide-cyclic GMP system is operational in both synaptic layers of retina and that it may play a more significant role in the inner retina.

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URBAN, PAUL-FRANCIS, MARLYSE ZAEPFEL, and PAUL REICHERT. "Glutamate binding in bovine retina." Biochemical Society Transactions 14, no. 3 (June 1, 1986): 611. http://dx.doi.org/10.1042/bst0140611.

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Bautista-Pérez, Rocio, Agustina Cano-Martínez, Elisa Gutiérrez-Velázquez, Martín Martínez-Rosas, Rosa M. Pérez-Gutiérrez, Francisco Jiménez-Gómez, and Javier Flores-Estrada. "Spinach Methanolic Extract Attenuates the Retinal Degeneration in Diabetic Rats." Antioxidants 10, no. 5 (May 3, 2021): 717. http://dx.doi.org/10.3390/antiox10050717.

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It has been suggested that spinach methanolic extract (SME) inhibits the formation of advanced glycation end products (AGEs), which are increased during diabetes progression, so it is important to know if SME has beneficial effects in the diabetic retina. In this study, in vitro assays showed that SME inhibits glycation, carbonyl groups formation, and reduced-thiol groups depletion in bovine serum albumin incubated either reducing sugars or methylglyoxal. The SME effect in retinas of streptozotocin-induced diabetic rats (STZ) was also studied (n = 10) in the normoglycemic group, STZ, STZ rats treated with SME, and STZ rats treated with aminoguanidine (anti-AGEs reference group) during 12 weeks. The retina was sectioned and immunostained for Nε-carboxymethyl lysine (CML), receptor RAGE, NADPH-Nox4, inducible nitric oxide synthase (iNOS), 3-nitrotyrosine (NT), nuclear NF-κB, vascular endothelial growth factor (VEGF), glial fibrillary acidic protein (GFAP), S100B protein, and TUNEL assay. Lipid peroxidation was determined in the whole retina by malondialdehyde (MDA) levels. The results showed that in the diabetic retina, SME reduced the CML-RAGE co-localization, oxidative stress (NOX4, iNOS, NT, MDA), inflammation (NF-κB, VEGF, S100B, GFAP), and apoptosis (p < 0.05). Therefore, SME could attenuate the retinal degeneration by inhibition of CML–RAGE interaction.

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Jones, Eugenia M. C. "Na+ - and Cl−-dependent neurotransmitter transporters in bovine retina: Identification and localization by in situ hybridization histochemistry." Visual Neuroscience 12, no. 6 (November 1995): 1135–42. http://dx.doi.org/10.1017/s0952523800006775.

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AbstractThe physiological actions of biogenic amine and amino-acid neurotransmitters are terminated by their removal from the synaptic cleft by specific high-affinity transport proteins. The members of the Na+- and Cl−-dependent neurotransmitter transporter family expressed in bovine retina and responsible for the uptake of biogenic amine and amino-acid neurotransmitters were identified using a reverse transcriptase-polymerase chain reaction-based approach. cDNA clones encoding bovine homologues of glycine (GLYT-1), γ-aminobutyric acid (GAT-1) creatine (CreaT), and orphan (NTT4) transporters were identified using this strategy. The expression pattern of mRNAs encoding these proteins in the retina was determined by in situ hybridization histochemistry GLYT-1 CreaT NTT4 and GAT-1 mRNAs were expressed in the retina by cells in the inner nuclear inner plex, iform and ganglion cell layers They were not expressed at detectable levels in the photoreceptor cells whose cell bodies are in the outer nuclear layer and are the most abundant cell type in the retina GLYT-1 mRNA was present exclusively in the proximal inner nuclear layer GAT-1 mRNA was localized to both the inner nuclear and ganglion cell layers CreaT mRNA was expressed in all cell types in the retina except photoreceptors and NTT4 mRNA was expressed by a sub subpoulation of cells in the ganglion cell laver. Elucidation of the expression pattern of these neurotransmitter transporter mRNAs in the retina provides a basis for studies of the role of glycine γ-aminobutyric acid and creatine transporters in retinal function.

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MANEU, VICTORIA, GUILLERMO GERONA, LAURA FERNÁNDEZ, NICOLÁS CUENCA, and PEDRO LAX. "Evidence of alpha 7 nicotinic acetylcholine receptor expression in retinal pigment epithelial cells." Visual Neuroscience 27, no. 5-6 (October 8, 2010): 139–47. http://dx.doi.org/10.1017/s0952523810000246.

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AbstractSome evidence suggests that retinal pigment epithelium (RPE) can express nicotinic acetylcholine receptors (nAChRs) as described for other epithelial cells, where nAChRs have been involved in processes such as cell development, cell death, cell migration, and angiogenesis. This study is designed to determine the expression and activity of α7 nAChRs in RPE cells. Reverse transcriptase (RT)-PCR was performed to test the expression of nicotinic α7 subunit in bovine RPE cells. Protein expression was determined by Western blot and by immunocytochemistry. Expression of nicotinic α7 subunits was also analyzed in cryostat sections of albino rat retina. Changes in protein expression were tested under hypoxic conditions. Functional nAChRs were studied by examining the Ca2+transients elicited by nicotine and acetylcholine stimulation in fura-2–loaded cells. Expression of endogenous modulators of nAChRs was analyzed by RT-PCR and Western blot in retina and RPE. Cultured bovine RPE cells expressed nicotinic receptors containing α7 subunit. RT-PCR amplified the expected specific α7 fragment. Western blotting showed expression at the protein level, with a specific band being found at 57 kDa in both cultured and freshly isolated RPE cells. Expression of nAChRs was confirmed for cultured cells by immunofluorescence. Immunohistochemistry confirmed α7 receptor expression in rat RPE retina. α7 receptor expression was down-regulated by long-term hypoxia. A small subpopulation of RPE cultured cells showed functional nAChRs, as evidenced by the selective response elicited by nicotine and acetylcholine stimulation. Expression of the endogenous nicotinic receptors’ modulator lynx1 was confirmed in bovine retina and RPE, and expression of lynx1 and other endogenous nicotinic receptor modulators (SLURP1 and RGD1308195) were also confirmed in rat retina. These results suggest that nAChRs could have a significant role in RPE, which may not be related to the traditional role in nerve transmission but could more likely be related to the nonneuronal cholinergic system in the eye.

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Hughes, Bret A., Gyanendra Kumar, Yukun Yuan, Anuradha Swaminathan, Denise Yan, Ashish Sharma, Lisa Plumley, Teresa L. Yang-Feng, and Anand Swaroop. "Cloning and functional expression of human retinal Kir2.4, a pH-sensitive inwardly rectifying K+ channel." American Journal of Physiology-Cell Physiology 279, no. 3 (September 1, 2000): C771—C784. http://dx.doi.org/10.1152/ajpcell.2000.279.3.c771.

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To identify novel potassium channel genes expressed in the retina, we screened a human retina cDNA library with an EST sequence showing partial homology to inwardly rectifying potassium (Kir) channel genes. The isolated cDNA yielded a 2,961-base pair sequence with the predicted open reading frame showing strong homology to the rat Kir2.4 (rKir2.4). Northern analysis of mRNA from human and bovine tissues showed preferential expression of Kir2.4 in the neural retina. In situ hybridization to sections of monkey retina detected Kir2.4 transcript in most retinal neurons. Somatic hybridization analysis and dual-color in situ hybridization to metaphase chromosomes mapped Kir2.4 to human chromosome 19 q13.1–q13.3. Expression of human Kir2.4 cRNA in Xenopus oocytes generated strong, inwardly rectifying K+ currents that were enhanced by extracellular alkalinization. We conclude that human Kir2.4 encodes an inwardly rectifying K+ channel that is preferentially expressed in the neural retina and that is sensitive to physiological changes in extracellular pH.

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Foy, W. L., C. Shaw, C. F. Johnston, and K. D. Buchanan. "Characterisation of tachykinins in bovine retina." Regulatory Peptides 18, no. 5-6 (September 1987): 348. http://dx.doi.org/10.1016/0167-0115(87)90204-7.

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Hanneken, Ludger, Gertrud Cremer-Bartels, Heinrich Gerding, and Kunibert Krause. "GTP-CH Activity in Bovine Retina." Pteridines 2, no. 1 (January 1990): 45–46. http://dx.doi.org/10.1515/pteridines.1990.2.1.45.

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GOTZES, SEBASTIAN, JAN de VENTE, and FRANK MÜLLER. "Nitric oxide modulates cGMP levels in neurons of the inner and outer retina in opposite ways." Visual Neuroscience 15, no. 5 (May 1998): 945–55. http://dx.doi.org/10.1017/s0952523898155141.

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In the mammalian retina, neuronal nitric oxide synthase (NOS) is mainly localized in subpopulations of amacrine cells. One function of nitric oxide (NO) is to stimulate soluble guanylate cyclases which in turn synthesize cGMP. We used an antibody specific for cGMP to demonstrate cGMP-like immunoreactivity (cG-IR) in bovine, rat, and rabbit retinae and investigated the effects on cGMP levels of both exogenously applied NO and of endogenously released NO. We found that cGMP levels in inner and outer retina were controlled in opposite ways. In the presence of the NO-donors SNP, SIN-1 or SNAP, cG-IR was prominent in neurons of the inner retina, mainly in cone bipolar cells, some amacrine and ganglion cells. Retinae incubated in IBMX showed weak cG-IR in bipolar cells. Glutamate increased cG-IR in the inner retina, presumably by stimulating endogenous NO release, whereas NOS inhibitors or GABA and glycine decreased cG-IR in bipolar cells by reducing NO release. In somata, inner segments and spherules of rod photoreceptors the situation was reversed. cG-IR was undetectable in the presence of NO-donors or glutamate, was moderate in IBMX-treated retinae, but increased strongly in the presence of NOS inhibitors or GABA/glycine. We conclude that NO is released endogenously in the retina. In the presence of NO, cGMP levels are increased in neurons of the inner retina, but are decreased in rods.

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Cuny, Robert, and George M. Malacinski. "Axolotl retina and lens development: mutual tissue stimulation and autonomous failure in the eyeless mutant retina." Development 96, no. 1 (July 1, 1986): 151–70. http://dx.doi.org/10.1242/dev.96.1.151.

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During eye development in the axolotl (Ambystoma mexicanum Shaw), morphogenetic movements bring together tissues from head epidermis, neuroectoderm and neural crest. The stages 0 to 14 of axolotl eye development were expanded from Rabl's (1898) stages 1 to 10 and correlated with Harrison's (1969) stages. At the onset of neurulation (stage 13 of Harrison), the head epidermis is already determined to form skin, and the neuroectoderm is committed to form brain, because these tissues develop autonomously in 60% Leibovitz L-15 culture medium. However, a sequence of mutual tissue interactions is necessary to stimulate eye development. When head epidermis and neuroectoderm were cocultured, eyes developed, containing retinas with photoreceptors (stage 8) and lenses with secondary lens fibres (stage 8). The first event needed in this case appears to be the secretion of a growth factor from the head epidermis which stimulates retina development from the neuroectoderm. When neuroectoderm cultures were exposed to nondialysable extracts (30μg ml−1) of an adult epidermis derivative, the bovine cornea, pigmented retinas (stage 6) and at higher concentrations (3000μg m−1) neural retinas developed (stage 6). In turn, lens formation is stimulated in the head epidermis by a retinaderived growth factor. A mutation that causes adult eyelessness (e eyeless, nonlethal, recessive) affects the earliest event in eye development (stage 1a), while a mutation that causes arrest of eye development (mi microphthalmic, lethal, recessive) acts in a later event (stage 8). Two possibilities have been considered in the case of mutation e: either the head epidermis does not secrete sufficient amounts of active growth factor, or the presumptive retina itself is defective. The latter statement turned out to be correct, because mutant e neural plates rarely developed early retina stages (stage 5) in organ culture when combined with wild-type head epidermis. On the other hand, wild-type neural plates formed advanced retinas (stage 8) in all cases when combined with mutant e head epidermis. As expected, no retina or lens developed when both neural plate and head epidermis were from mutant e donors. The heterozygous presence of genes e and r (renal insufficiency, lethal, recessive) produces duplications of the presumptive retina at the optic stalk. This observation is consistent with the notion that the mutation e, assisted by the r locus, causes a primary failure in the presumptive retinal region.

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Remez, Lital, Ben Cohen, Mariela J. Nevet, Leah Rizel, and Tamar Ben-Yosef. "TULP1 and TUB Are Required for Specific Localization of PRCD to Photoreceptor Outer Segments." International Journal of Molecular Sciences 21, no. 22 (November 17, 2020): 8677. http://dx.doi.org/10.3390/ijms21228677.

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Photoreceptor disc component (PRCD) is a small protein which is exclusively localized to photoreceptor outer segments, and is involved in the formation of photoreceptor outer segment discs. Mutations in PRCD are associated with retinal degeneration in humans, mice, and dogs. The purpose of this work was to identify PRCD-binding proteins in the retina. PRCD protein-protein interactions were identified when implementing the Ras recruitment system (RRS), a cytoplasmic-based yeast two-hybrid system, on a bovine retina cDNA library. An interaction between PRCD and tubby-like protein 1 (TULP1) was identified. Co-immunoprecipitation in transfected mammalian cells confirmed that PRCD interacts with TULP1, as well as with its homolog, TUB. These interactions were mediated by TULP1 and TUB highly conserved C-terminal tubby domain. PRCD localization was altered in the retinas of TULP1- and TUB-deficient mice. These results show that TULP1 and TUB, which are involved in the vesicular trafficking of several photoreceptor proteins from the inner segment to the outer segment, are also required for PRCD exclusive localization to photoreceptor outer segment discs.

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ROTSTEIN, N. P., G. L. PENNACCHIOTTI, H. SPRECHER, and M. I. AVELDAÑO. "Active synthesis of C24:5, n-3 fatty acid in retina." Biochemical Journal 316, no. 3 (June 15, 1996): 859–64. http://dx.doi.org/10.1042/bj3160859.

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The formation of 14C-labelled long-chain and very-long-chain (n-3) pentaenoic and hexaenoic fatty acids was studied in bovine retina by following the metabolism of [14C]docosapentaenoate [C22:5, n-3 fatty acid (22:5 n-3)], [14C]docosahexaenoate (22:6 n-3), and [14C]acetate. With similar amounts of 22:5 n-3 and 22:6 n-3 as substrates, the former was actively transformed into 24:5 n-3, whereas the latter was virtually unmodified. Labelled 24:5, 26:5, 24:6 and 22:6 were formed from [1-14C]22:5 n-3, showing that pentaenoic fatty acids including 24:5 n-3 can be elongated and desaturated within the retina. When retinal microsomes were incubated with [1-14C]22:5 n-3, 24:5 n-3 was the only fatty acid formed. In retinas incubated with [14C]acetate, 24:5 n-3 was the most highly labelled fatty acid among the polyenes synthesized, 24:6 n-3 being a minor product. Such selectivity in the elongation of two fatty acids identical in length, 22:5 n-3 and 22:6 n-3, despite the fact that 22:5 is a minor and 22:6 a major fatty acid constituent of retina, suggests that the active formation of 24:5 n-3 plays a key role in n-3 polyunsaturated fatty acid (PUFA) metabolism. This compound might give rise to even longer pentaenes via elongation, and to the major PUFAs of retina, 22:6 n-3, by 6-desaturation and chain shortening. Of all retinal lipids, a minor component, triacylglycerol (TG), incorporated the largest amounts of [14C]22:5 and 22:6. TG also concentrated most of the [14C]24:5 formed in retina, whether from [14C]22:5 n-3 or from [14C]acetate, suggesting an important role for this lipid in supporting PUFA metabolism and the synthesis of 22:6 n-3.

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22

Kuo, Che-Hui, Kanato Yamagata, Robert K. Moyzis, Mark W. Bitensky, and Naomasa Miki. "Multiple opsin mRNA species in bovine retina." Molecular Brain Research 1, no. 3 (December 1986): 251–60. http://dx.doi.org/10.1016/0169-328x(86)90031-8.

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23

Gosbell, Andrew D., Ian Favilla, and Paula Jablonski. "The location of insulin receptors in bovine retina and isolated retinal cells." Clinical & Experimental Ophthalmology 30, no. 2 (February 2002): 124–30. http://dx.doi.org/10.1046/j.1442-6404.2002.00499.x.

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24

Snow, D. M., M. Watanabe, P. C. Letourneau, and J. Silver. "A chondroitin sulfate proteoglycan may influence the direction of retinal ganglion cell outgrowth." Development 113, no. 4 (December 1, 1991): 1473–85. http://dx.doi.org/10.1242/dev.113.4.1473.

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In the developing retina, retinal ganglion cell (RGC) axons elongate toward the optic fissure, even though no obvious directional restrictions exist. Previous studies indicate that axon-matrix interactions are important for retinal ganglion cell axon elongation, but the factors that direct elongation are unknown. Chondroitin sulfate proteoglycan (CS-PG), a component of the extracellular matrix, repels elongating dorsal root ganglion (DRG) axons in vitro and is present in vivo in the roof plate of the spinal cord, a structure that acts as a barrier to DRG axons during development. In this study, we examined whether CS-PG may regulate the pattern of retinal ganglion cell outgrowth in the developing retina. Immunocytochemical analysis showed that CS-PG was present in the innermost layers of the developing rat retina. The expression of CS-PG moved peripherally with retinal development, always remaining at the outer edge of the front of the developing axons. CS-PG was no longer detectable with immunocytochemical techniques when RGC axon elongation in the retina is complete. Results of studies in vitro showed that CS-PG, isolated from bovine nasal cartilage and chick limb, was inhibitory to elongating RGC axons and that RGC growth cones were more sensitive to CS-PG than were DRG neurites tested at the same concentrations of CS-PG. The behavior of retinal growth cones as they encounter CS-PG was characterized using time-lapse video microscopy. Filopodia of the RGC growth cones extended to and sampled the CS-PG repeatedly. With time, the growth cones turned to avoid outgrowth on the CS-PG and grew only on laminin. While numerous studies have shown the presence of positive factors within the retina that may guide developing RGC axons, this is the first demonstration of an inhibitory or repelling molecule in the retina that may regulate axon elongation. Taken together, these data suggest that the direction of RGC outgrowth in the retina may be regulated by the proper ratio of growth-promoting molecules, such as laminin, to growth-inhibiting molecules, like CS-PG, present in the correct pattern and concentrations along the retinal ganglion cell pathway.

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25

Wagner, J. A., and P. A. D'Amore. "Neurite outgrowth induced by an endothelial cell mitogen isolated from retina." Journal of Cell Biology 103, no. 4 (October 1, 1986): 1363–67. http://dx.doi.org/10.1083/jcb.103.4.1363.

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Retina-derived growth factor (RDGF) is a polypeptide growth factor purified from salt extracts of bovine retinas on the basis of its mitogenic activity for capillary endothelial cells (EC) and BALB/c 3T3 cells. RDGF is angiogenic in vivo. We show here that RDGF induces neurite extension by PC12 cells and that this neurite outgrowth is dramatically potentiated by heparin. Neurite formation elicited by RDGF in the presence of heparin cannot be distinguished from that elicited by nerve growth factor (NGF) either by the time course of neurite formation or by the morphology of the neurites at the level of the light microscope. Neurite outgrowth induced by either purified RDGF or by a crude retinal extract is not blocked by antibodies to NGF. Furthermore, neurite outgrowth induced by NGF is not potentiated by heparin and NGF is not mitogenic for capillary EC. Thus, RDGF has profound regulatory effects on cell types of very different embryonic origins. These results indicate that the physiological role for this growth factor may be far more complex than previously suspected and suggest that the formation of neural connections and the process of vascularization may unexpectedly share common regulatory elements.

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26

Saari, John C., and D. Lucille Bredberg. "Purification of cellular retinaldehyde-binding protein from bovine retina and retinal pigment epithelium." Experimental Eye Research 46, no. 4 (April 1988): 569–78. http://dx.doi.org/10.1016/s0014-4835(88)80013-7.

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27

Morse, Lawrence S., Ken Steinsapir, Jack Terrell, and Yossi Sidikaro. "Localization of gamma glutamyl transpeptidase in bovine retina." Current Eye Research 8, no. 11 (January 1989): 1131–40. http://dx.doi.org/10.3109/02713688909000038.

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28

Day, Nancy S., Abboud J. Ghalayini, and Robert E. Anderson. "Membrane-associated inositol hexakisphosphate binding in bovine retina." Current Eye Research 14, no. 9 (January 1995): 851–55. http://dx.doi.org/10.3109/02713689508995808.

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29

Ferreira, Paulo A., Joanne T. Hom, and William L. Pak. "Retina-specifically Expressed Novel Subtypes of Bovine Cyclophilin." Journal of Biological Chemistry 270, no. 39 (September 29, 1995): 23179–88. http://dx.doi.org/10.1074/jbc.270.39.23179.

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30

SHALLAL, ASAAD, and CAROLYN A. CONVERSE. "d-[3H]Galactose incorporation in the bovine retina." Biochemical Society Transactions 14, no. 3 (June 1, 1986): 612–13. http://dx.doi.org/10.1042/bst0140612.

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31

KULKARNI, PRASAD S. "Arachidonic Acid Metabolism in Human and Bovine Retina." Journal of Ocular Pharmacology and Therapeutics 7, no. 2 (January 1991): 135–39. http://dx.doi.org/10.1089/jop.1991.7.135.

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32

Venturini, C. M., R. G. Knowles, R. M. J. Palmer, and S. Moncada. "Synthesis of nitric oxide in the bovine retina." Biochemical and Biophysical Research Communications 180, no. 2 (October 1991): 920–25. http://dx.doi.org/10.1016/s0006-291x(05)81153-2.

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33

Tsin, Andrew T. C., and Kwok-Wai Lam. "Retinyl palmitate hydrolase activity in the bovine retina." Biochemical and Biophysical Research Communications 134, no. 3 (February 1986): 1209–14. http://dx.doi.org/10.1016/0006-291x(86)90379-7.

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34

Zhou, Jiehao, Shikun He, Ning Zhang, Christine Spee, Peng Zhou, Stephen J. Ryan, Ram Kannan, and David R. Hinton. "Neutrophils Compromise Retinal Pigment Epithelial Barrier Integrity." Journal of Biomedicine and Biotechnology 2010 (2010): 1–10. http://dx.doi.org/10.1155/2010/289360.

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We hypothesized that neutrophils and their secreted factors mediate breakdown of the integrity of the outer blood-retina-barrier by degrading the apical tight junctions of the retinal pigment epithelium (RPE). The effect of activated neutrophils or neutrophil cell lysate on apparent permeability of bovine RPE-Choroid explants was evaluated by measuring[H]mannitol flux in a modified Ussing chamber. The expression of matrix metalloproteinase- (MMP-) 9 in murine peritoneal neutrophils, and the effects of neutrophils on RPE tight-junction protein expression were assessed by confocal microscopy and western blot. Our results revealed that basolateral incubation of explants with neutrophils decreased occludin and ZO-1 expression at 1 and 3 hours and increased the permeability of bovine RPE-Choroid explants by >3-fold (P<.05). Similarly, basolateral incubation of explants with neutrophil lysate decreased ZO-1 expression at 1 and 3 hours (P<.05) and increased permeability of explants by 75%. Further, we found that neutrophils prominently express MMP-9 and that incubation of explants with neutrophils in the presence of anti-MMP-9 antibody inhibited the increase in permeability. These data suggest that neutrophil-derived MMP-9 may play an important role in disrupting the integrity of the outer blood-retina barrier.

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35

BOLLIMUNTHA, SUNITHA, ERIC CORNATZER, and BRIJ B. SINGH. "Plasma membrane localization and function of TRPC1 is dependent on its interaction with β-tubulin in retinal epithelium cells." Visual Neuroscience 22, no. 2 (March 2005): 163–70. http://dx.doi.org/10.1017/s0952523805222058.

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Mammalian homologues of the Drosophila canonical Transient Receptor Potential (TRPC) protein have been proposed to encode the store-operated Ca2+ influx (SOC) channel(s). This study examines the role of TRPC1 in the SOC mechanism of retinal cells. htrpc1 transcript was detected in bovine retinal and in human adult retinal pigment epithelial (ARPE) cells. Western blot analysis also confirmed the expression of TRPC1 protein in neuronal cells including retina and ARPE cells. To determine the role of TRPC1 protein in retinal cells, TRPC1 was recombinantly expressed in ARPE cells and changes in intracellular Ca2+ were analyzed. ARPE cells stably transfected with htrp1 cDNA displayed 2-fold higher Ca2+ influx with no significant increase in the basal influx. Consistent with this the overexpressed TRPC1 protein was localized in the plasma membrane region of ARPE cells. Interestingly, both bovine retinal tissues and ARPE cells showed that TRPC1 protein co-localizes and could be co-immunoprecipitated with β-tubulin. Disruption of tubulin by colchicine significantly decreased both plasma membrane staining of the TRPC1 protein and Ca2+ influx in ARPE cells. These results suggest that TRPC1 channel protein is expressed in retinal cells, further, targeting/retention of the TRPC1 protein to the plasma membrane in retinal cells is mediated via its interaction with β-tubulin.

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36

Postnikova, Olga A., Igor B. Rogozin, William Samuel, German Nudelman, Vladimir N. Babenko, Eugenia Poliakov, and T. Michael Redmond. "Volatile Evolution of Long Non-Coding RNA Repertoire in Retinal Pigment Epithelium: Insights from Comparison of Bovine and Human RNA Expression Profiles." Genes 10, no. 3 (March 8, 2019): 205. http://dx.doi.org/10.3390/genes10030205.

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Currently, several long non-coding RNAs (lncRNAs) (TUG1, MALAT1, MEG3 and others) have been discovered to regulate normal visual function and may potentially contribute to dysfunction of the retina. We decided to extend these analyses of lncRNA genes to the retinal pigment epithelium (RPE) to determine whether there is conservation of RPE-expressed lncRNA between human and bovine genomes. We reconstructed bovine RPE lncRNAs based on genome-guided assembly. Next, we predicted homologous human transcripts based on whole genome alignment. We found a small set of conserved lncRNAs that could be involved in signature RPE functions that are conserved across mammals. However, the fraction of conserved lncRNAs in the overall pool of lncRNA found in RPE appeared to be very small (less than 5%), perhaps reflecting a fast and flexible adaptation of the mammalian eye to various environmental conditions.

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37

Lüke, Matthias, Marco Weiergräber, Carl Brand, Siarhei A. Siapich, Mohammed Banat, Jürgen Hescheler, Christoph Lüke, and Toni Schneider. "The isolated perfused bovine retina—A sensitive tool for pharmacological research on retinal function." Brain Research Protocols 16, no. 1-3 (December 2005): 27–36. http://dx.doi.org/10.1016/j.brainresprot.2005.09.001.

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38

Januschowski, Kai, Sebastian Mueller, Rebecca Dollinger, Sven Schnichels, Johanna Hofmann, Martin S. Spitzer, Karl-Ulrich Bartz-Schmidt, Peter Szurman, and Sebastian Thaler. "Investigating retinal toxicity of tempol in a model of isolated and perfused bovine retina." Graefe's Archive for Clinical and Experimental Ophthalmology 252, no. 6 (May 2, 2014): 935–41. http://dx.doi.org/10.1007/s00417-014-2632-4.

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39

Lam, Kwok-Wai, Lu Wang, Bor-Shyue Hong, and Donald Treble. "Purification of phospholipid hydroperoxide glutathione peroxidase from bovine retina." Current Eye Research 12, no. 1 (January 1993): 9–15. http://dx.doi.org/10.3109/02713689308999490.

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40

Bugnon, Olivier, Nicolas C. Schaad, and Michel Schorderet. "Nitric oxide modulates endogenous dopamine release in bovine retina." NeuroReport 5, no. 4 (January 1994): 401–4. http://dx.doi.org/10.1097/00001756-199401120-00007.

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41

Brann, Mark R., and W. Scott Young. "Dopamine receptors are located on rods in bovine retina." Neuroscience Letters 69, no. 3 (September 1986): 221–26. http://dx.doi.org/10.1016/0304-3940(86)90483-0.

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42

Pautler, E. L., J. A. Maga, and C. Tengerdy. "A pharmacologically potent natural product in the bovine retina." Experimental Eye Research 42, no. 3 (March 1986): 285–88. http://dx.doi.org/10.1016/0014-4835(86)90062-x.

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43

Zuo, Yuan, Ponniah Selvakumar, and Rajendra K. Sharma. "Molecular cloning and biochemical characterization of bovine retina calcineurin." Molecular and Cellular Biochemistry 333, no. 1-2 (July 22, 2009): 73–82. http://dx.doi.org/10.1007/s11010-009-0206-2.

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44

Gaidarov, I. O., O. N. Suslov, and N. G. Abdulaev. "Enzymes of the cyclic GMP metabolism in bovine retina." FEBS Letters 335, no. 1 (November 29, 1993): 81–84. http://dx.doi.org/10.1016/0014-5793(93)80444-y.

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45

Pautler, E. L., C. Tengerdy, J. Beyer, and D. Beezley. "Modification of leucine transport across bovine pigment epithelium by metabolic stress." American Journal of Physiology-Cell Physiology 257, no. 5 (November 1, 1989): C940—C947. http://dx.doi.org/10.1152/ajpcell.1989.257.5.c940.

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The transport of leucine in the apical-to-basal (retina to choroid) direction across the isolated bovine retinal pigment epithelium is mediated predominantly by the L amino transport system at low carrier (10 microns) concentrations. There is no evidence of an active or facilitated transport system operating in the opposite direction. The identification of the L system is based on the lack of sodium dependence, specific inhibition of leucine transport by 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH), and the demonstration of trans-stimulation. Lysine, glutamate, and 2-methylaminoisobutyric acid (MeAIB) did not provide any competitive inhibition. Ouabain and iodoacetate were also ineffective in modifying leucine transport. The transport mediated by the L system was markedly temperature sensitive, whereas no temperature dependence was apparent in the transport of leucine in the basal-to-apical direction (choroid to retina). When treated with dinitrophenol (DNP), the transport of leucine in the apical-to-basal direction was greatly enhanced, but no effect was observed on the leucine movement in the opposite direction. Azide and rotenone had an effect similar to DNP, as did reducing the partial pressure of O2 to less than 40 Torr. The enhancement of transport appeared to be mediated by the activation of an ancillary system, since it was susceptible to different classes of metabolic and competitive inhibitors as well as the observed ionic dependency. After DNP treatment, the transport of leucine was inhibited by lysine and BCH, revealed a sodium dependence, and could be inhibited by iodoacetate. The characteristics of the enhanced transport appear to be similar to those of the recently described G system(s) of amino acid transport.

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46

Rotstein, N. P., and M. I. Aveldaño. "Synthesis of very long chain (up to 36 carbon) tetra, penta and hexaenoic fatty acids in retina." Biochemical Journal 249, no. 1 (January 1, 1988): 191–200. http://dx.doi.org/10.1042/bj2490191.

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The synthesis of very long chain (C24 to C36) polyunsaturated (four, five and six double bonds) fatty acids (VLCPUFA) is investigated in bovine retina using [14C]acetate. Saturates on the one hand (mainly palmitate), and polyenes on the other (mainly VLCPUFA), incorporate most of the label found in lipids. Phosphatidylcholine (PC) is the most highly labelled lipid class, since both types of 14C-labelled fatty acids, but especially this novel series of VLCPUFA, are concentrated in this phospholipid. Radioactivity from [14C]acetate is found in very long chain tetra, penta and hexaenoic fatty acids of PC. The labelling of 20:4(n − 6), 20:5(n − 3), 22:5(n − 6) and 22:6(n − 3) is much lower than that of longer polyenes of each of these series, indicating that VLCPUFA are synthesized in situ by successive elongations of the above polyenes, pre-existing in retina lipids. In various subcellular fractions isolated from retinas after incubations with [14C]acetate (including cytosol, microsomes, mitochondria and photoreceptor membranes), the labelling of the VLCPUFA of PC is very high, even at relatively short intervals of incubation. The results suggest that not only the synthesis but also the intracellular traffic among membranes of VLCPUFA-containing species of PC are very active processes in the retina.

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47

Reddy, P. Seshidhar, Neeraja Idamakanti, Yan Chen, Tyler Whale, Lorne A. Babiuk, Majid Mehtali, and Suresh Kumar Tikoo. "Replication-Defective Bovine Adenovirus Type 3 as an Expression Vector." Journal of Virology 73, no. 11 (November 1, 1999): 9137–44. http://dx.doi.org/10.1128/jvi.73.11.9137-9144.1999.

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ABSTRACT Although recombinant human adenovirus (HAV)-based vectors offer several advantages for somatic gene therapy and vaccination over other viral vectors, it would be desirable to develop alternative vectors with prolonged expression and decreased toxicity. Toward this objective, a replication-defective bovine adenovirus type 3 (BAV-3) was developed as an expression vector. Bovine cell lines designated VIDO R2 (HAV-5 E1A/B-transformed fetal bovine retina cell [FBRC] line) and 6.93.9 (Madin-Darby bovine kidney [MDBK] cell line expressing E1 proteins) were developed and found to complement the E1A deletion in BAV-3. Replication-defective BAV-3 with a 1.7-kb deletion removing most of the E1A and E3 regions was constructed. This virus could be grown in VIDO R2 or 6.93.9 cells but not in FBRC or MDBK cells. The results demonstrated that the E1 region of HAV-5 has the capacity to transform bovine retina cells and that the E1A region of HAV-5 can complement that of BAV-3. A replication-defective BAV-3 vector expressing bovine herpesvirus type 1 glycoprotein D from the E1A region was made. A similar replication-defective vector expressing the hemagglutinin-esterase gene of bovine coronavirus from the E3 region was isolated. Although these viruses grew less efficiently than the replication-competent recombinant BAV-3 (E3 deleted), they are suitable for detailed studies with animals to evaluate the safety, duration of foreign gene expression, and ability to induce immune responses. In addition, a replication-competent recombinant BAV-3 expressing green fluorescent protein was constructed and used to evaluate the host range of BAV-3 under cell culture conditions. The development of bovine E1A-complementing cell lines and the generation of replication-defective BAV-3 vectors is a major technical advancement for defining the use of BAV-3 as vector for vaccination against diseases of cattle and somatic gene therapy in humans.

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48

Fesser, Adrian C. E., Leslie C. Dickson, James D. MacNeil, John R. Patterson, Stephen Lee, and Ronald Gedir. "Determination of β-Agonists in Liver and Retina by Liquid Chromatography-Tandem Mass Spectrometry." Journal of AOAC INTERNATIONAL 88, no. 1 (January 1, 2005): 61–69. http://dx.doi.org/10.1093/jaoac/88.1.61.

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Abstract A liquid chromatography-tandem mass spectrometry (LC/MS/MS) method for the determination of bromobuterol, cimaterol, clenbuterol, clenpenterol, hydroxymethylclenbuterol, isoxsuprine, mabuterol, ractopamine, ritrodrine, salbutamol, terbutaline, and tulobuterol residues in bovine liver and retina is reported. This procedure uses enzymatic digestion, liquid–liquid extraction, and cleanup on Oasis HLB solid-phase extraction cartridges, followed by determination of the residues by LC-tandem quadrupole MS using atmospheric pressure chemical ionization in the positive ion mode. Overall average recoveries ranged from 23 to 76% for liver and 34 to 77% for retina. The mean values for samples fortified at levels between 0.5–2.0 μg/kg (liver) and 5–20 μg/kg (retina) agreed within 98–118% of the spiked levels, with coefficients of variation ranging from 6 to 20%. The decision limits, CCα, ranged from 0.1 to 0.3 μg/kg for liver, 1–3 μg/kg for retina, and detection capabilities, CCβ, from 0.2–0.5 μg/kg for liver and 2–5 μg/kg for retina.

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49

Fliesler, Steven J., and George J. Schroepfer. "In Vitro Metabolism of Mevalonic Acid in the Bovine Retina." Journal of Neurochemistry 46, no. 2 (February 1986): 448–60. http://dx.doi.org/10.1111/j.1471-4159.1986.tb12989.x.

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50

Mori, Hideo, Kimio Fujii, Shigehiro Morikawa, Shinkichi Taniguchi, Motokazu Fujiwara, and Motohatsu Fujiwara. "Enzymatic properties of phospholipid base-exchange reactions in bovine retina." Japanese Journal of Pharmacology 40 (1986): 242. http://dx.doi.org/10.1016/s0021-5198(19)59473-2.

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Journal articles on the topic 'Bovine retina'

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