The distribution of caveolin isoforms was previouslyevaluated in the retinas of different species, but has notyet been described in the primate retina. In this study, thedistribution of caveolins was assessed via immunochemistryusing isoform-specific antibodies in the retina of the black-and-white ruffed lemur. Here, we report the presence of avariety of caveolin isoforms in many layers of the lemurretina. As normal human retinas were not available forresearch and the retinas of primates are fairly similar tothose of humans, the lemur retina can be utilized as amodel for caveolin distribution in normal humans.
Animals ; Caveolins/*metabolism ; Immunohistochemistry ; Lemur/*metabolism ; Male ; Protein Isoforms ; Retina/*metabolism

Aging/metabolism* ; Animals ; Gene Expression Regulation ; Macaca fascicularis ; Retina/metabolism* ; Single-Cell Analysis

OBJECTIVETo investigate the changes of cholinergic neurotrophic factors (CNTF) protein at different time points and the distribution of CNTF in rabbit retina after exposure to high power microwave (HPM), in order to determine the changes rule of CNTF protein.

METHODSThe rabbits were irradiated by HPM (peak power 90 W/cm(2)) for 15 min respectively, and then killed at 0, 3, 6, 12, 24 and 72 h after irradiation. The changes of CNTF protein were investigated by immunohistochemistry and semi-quantity analysis.

RESULTSCNTF protein was distributed in full retinal layers, special in the cell membrane and cytoplasm. HPM irradiation could immediately down-regulated CNTF protein expression at 0 h, up-regulated and arrived at peak level at 6 h (P<0.05 vs 0 h group), and then kept control level.

CONCLUSIONHPM may cause acute retinal injure and change the expression of CNTF protein in rabbit retina. These effects show the time-dependent feature. These results suggest that CNTF activation plays a central role in the retinal injures induced by HPM, and supplies a therapy method by using foreign-aid CNTF to remedy the retinal injure induced by HPM.

Animals ; Ciliary Neurotrophic Factor ; metabolism ; Female ; Male ; Microwaves ; adverse effects ; Rabbits ; Retina ; metabolism ; radiation effects

Animals ; Ciliary Neurotrophic Factor ; genetics ; metabolism ; Microwaves ; RNA, Messenger ; genetics ; Rabbits ; Retina ; metabolism ; radiation effects

BACKGROUNDGlaucoma, an irreversible optic nerve neuropathy, always results in blindness. This study aimed to evaluate glaucoma-like features in the rat episcleral vein cauterization (EVC) model by multiple in vivo and in vitro evidences.

METHODSWistar rat was used in this study. The elevated intraocular pressure (IOP) was induced by cauterization of three episcleral veins. IOP was monitored with Tono-Pen XL tonometer. Time-dependent changes to the neuronal retinal layers were quantified by Fourier domain-optical coherence tomography. The function of retina was evaluated by electroretinogram (ERG). Survival of retinal ganglion cells (RGCs) was quantified by retrograde labeling. Histology study was performed with retinal sections stained with hematoxylin-eosin, glial fibrillary acidic protein, and neuronal nuclear antigen. Retina and aqueous humor protein were extracted and cytotoxic protein tumor necrosis factor alpha (TNF-α) and alpha-2 macroglobulin (α2m) were measured with Western blotting.

RESULTSEVC is a relatively facile intervention, with low failure rates (<5%). After surgical intervention, chronic mild IOP elevation (about 1.6-fold over normal, P < 0.05) was induced for at least 6 weeks without requiring a second intervention. High IOP causes chronic and progressive loss of RGCs (averaging about 4% per week), progressive thinning of neuronal retinal layers (3-5 μm per week), and reduction of a- and b-wave in ERG. EVC method can also induce glial cell activation and alterations of inflammation proteins, such as TNF-α and α2m.

CONCLUSIONEVC method can establish a robust, reliable, economic and highly reproducible glaucomatous animal model.

Animals ; Disease Models, Animal ; Electroretinography ; Female ; Glaucoma ; metabolism ; pathology ; Rats ; Rats, Wistar ; Retina ; metabolism ; pathology ; Retinal Neurons ; metabolism

OBJECTIVEIntravitreal (IVT) injection has become one of the most commonly performed ophthalmologic procedures. We investigated the changes in retinal function and proteomics in rabbits receiving IVT injection of PBS to evaluate the safety of IVT injection.

METHODSTwenty Chinchilla rabbits were subjected to IVT injection of 50 µL PBS in the right eyes. On days 0, 4, 7 and day 14, the retinas of the rabbits were isolated after routine ophthalmic and electroretinogram examinations. The protein expressions in the retinas were quantified using tandem mass tag (TMT)-labeling coupled with LC-MS/MS, and bioinformatic analysis of the differentially expressed proteins (DEPs) was performed based on KEGG database to identify significantly enriched pathways. Functional network of the significant DEPs was analyzed using STRING.

RESULTSNo noticeable fundus or functional changes occurred in the rabbit eyes following IVT injection of PBS. A total of 6042 retinal proteins were identified in the retina following the injection, among which 49 proteins (0.81%) exhibited over 5.0-fold up-regulation or over 80% down- regulation relative to the control. Most of the distinctly up-regulated or down-regulated proteins were associated with the cytoskeleton. Significantly enriched pathways involved focal adhesion, tight junction, riboflavin metabolism, extracellular matrix-receptor interaction and regulation of actin cytoskeleton. Functional network analysis showed that ACTC1 and ISG15 played central roles in the protein interaction networks.

CONCLUSIONIVT PBS injection in rabbits causes alterations in proteins associated with cell adhesion, morphology, migration, differentiation, signal transduction and riboflavin metabolism, but the alterations of the retinal proteins appear not sufficient to cause observable pathology of the retina.

Animals ; Chromatography, Liquid ; Electroretinography ; Eye Proteins ; metabolism ; Intravitreal Injections ; Proteome ; metabolism ; Proteomics ; Rabbits ; Retina ; metabolism ; Tandem Mass Spectrometry

BACKGROUNDThe form deprivation (FD) reduces spatial contrasts and induces myopia. Nitric oxide and cyclic guanosine monophosphate (cGMP) are involved in visual signal transmission. This study investigated changes in nitric oxide synthase (NOS) activity and cGMP concentration in ocular tissues in acute and chronic form deprivation myopia.

METHODSGuinea pigs had one eye covered by translucent glass for 7, 14 or 21 days. Untreated litter mates were used as controls. NOS activity and cGMP concentrations in the retinal, choroidal and scleral tissues of FD eyes and control eyes were analyzed by radioimmunoassay after various durations of FD. The expression of NOS subtypes was identified by immunohistochemistry.

RESULTSMyopia was successfully induced in FD eyes after 14 days. Compared with control groups, the retinal NOS activity and cGMP concentrations in the FD eyes significantly increased after 14 and 21 days while the retinal NOS activity in the FD eyes was transiently suppressed by 7 days of FD. The NOS activity and cGMP concentrations of choroid and sclera in the FD eyes were higher than in the control groups at 21 days. The three isoenzymes of nitric oxide synthase were detected in the ocular tissues of guinea pigs.

CONCLUSIONSThe NOS activity and cGMP concentrations were upregulated after chronic FD and the retinal NOS activity was transiently suppressed at acute FD. The function of elevated NOS activity may be mediated by cGMP.

Animals ; Cyclic GMP ; analysis ; Guinea Pigs ; Immunohistochemistry ; Myopia ; metabolism ; Nitric Oxide ; physiology ; Nitric Oxide Synthase ; metabolism ; Refractive Errors ; Retina ; metabolism

The experiments were performed on albino rabbits in which retinal ischemia had been produced by elevating tbe intraocular pressure to 120 mmHg by canulation of the anterior chamber and serial electroretinograms were recorded. The animals were divided into 3 groups; the first served as a normal control,the second received 30cc of 50% glucose solution intravenously, and the third received 2 units of insulin intramuscularly. The light stimuli used was 200 lux at the animal's eye and its duration was O.1 second. The contents of glucose and glycogen together were shown in table 1 and figure 1. The content was the greatest iri group II and the least in group III. After elevation of the intraocular pressure, b-wave gradually decreased and finally extinguished. The disappearance time of the b-wave in 3 groups of animals was shown in table 3 and figure 3. The survival time of the b-wave was longest in group II and shortest in group III. After 15 minutes of retinal ischemia, the intraocular pressure was returned to 15mmHg and the retinal blood flow was restored. The b-wave reappeared and the time at which b-wave recovers 50% of the original amplitude was shown in table 4 and figure 4. The b-wave recovers the quickest in group 2 animals and latest in group 3. In conclusion, when the glucose content of the retina is high, the resistance of the b-wave against the retinal ischemia is high and its recovery after restoration of the blood flow is quick. The significance of the glucose content of the retina and its role in retinal metabolism were discussed.
Animals ; Anterior Chamber ; Glucose* ; Glycogen ; Insulin ; Intraocular Pressure ; Ischemia* ; Metabolism ; Rabbits ; Retina* ; Retinaldehyde*

Human optic nerve injury and its associated neurodegenerative diseases are often followed by permanent vision loss.Stem cell therapy has long been considered a promising mode to treat retinal degenerative diseases.Recent studies revealed that there are silent retinal stem cells in the eyes of mammals and even humans.These stem cells can be activated again under certain conditions and differentiate into retinal neurons to repair the damaged retina.Wnt signaling pathway plays a crucial role in conducting growth-stimulating signals and regulates cell proliferation,differentiation and apoptosis.This article review the regulatory effect of Wnt signaling pathway on stem cells-based retinal regeneration and the sources of retinal stem cells.
Animals ; Cell Differentiation ; Humans ; Regeneration ; Retina ; growth & development ; Stem Cells ; metabolism ; Wnt Signaling Pathway

In the present study the specific and nonspecific cholinesterase activities of the rabbit's retinae in the fetus, the neonatal, the light-isolated, and the reopened group, which consisted of 65 healthy young rabbits, weighing about 300 to 500 gm, 33 rabbit's fetuses, and neonatal rabbits, were histochemically ovserved by means of the cholinesterase method recommended by Gerebtzoff (1953) and the embedding and sectioning method pesented by Koelle and Friedenwald (1950). Cholinesterase activity of the retinae in the 15 days fetuses was not present but began to develop in the 20 days fetuses. In the 1 week group after suturing the eyelids, the most remarkable activity of specific and nonspecific cholinesterase was observed in the posterior polar area. The nearer to the peripheral area of the retina the weaker the enzymetic activities became. In the 2 weeks group after suturing eyelids, the enzymatic activity was reduced. In the 4, and 8weeks groups after suturing the eyelides, the enzymatic activities were remarkably reduced. In the l4 days after reopening eyelide, which group has previously been kept under the condition of light isolation for 4 weeks, enzymatic activities were fairly recovered and compared with the normal control group. Consequently it is histochemically deduced that the gradual change of specific cholinesterase activities in the rabbit's retinae was closely related to the visual function.
Animals ; Animals, Newborn/enzymology ; Cholinesterases/*metabolism ; Histocytochemistry ; *Rabbits ; Retina/embryology/*enzymology