PURPOSE: To explore the pathogenesis of anisometropic and amblyopias. METHODS:To carry out on monocular and binocular atropinized cat models during the developmental period for anisometropia and ametropia ,and measure the cytosomal sectional area and some parameters of the dendric field from the dorsal lateral geniculate nuclei (dLGN)of adult cats by using Golgi-Cox staining. RESULIS:The changes of cytosomal sectional areas and parameters about dendric fields in the dLGN of experimental cats were as following:significant differences between cells of dLGN's A1 lamina by the monocular atropinized eyes and normal ones, binocular atropinized eyea and normal ones;no significant difference between tbat driven by the monoular and binocular atropinized eyes. CONCLUSIONS:There might be resemble pathogenesis between anisomelropic and ametropic amblyopias. （Chin J Ocul Fundus Dis,1996,12:153-156）
Purpose To evaluate differences in the pattern of optic disc and retinal nerve fiber layer (RNFL) damage in normal-tension glaucoma (NTG) and high-tension glaucoma (HTG) patients. Methods We enrolled 49 eyes of 49 patients:30 NTG (IOP≤21 mm Hg,1 mm Hg=0.133 kPa), 19 HTG(IOP≥25 mm Hg). Mean age was 59.2±12.3 (range, 36-75) for HTG patients, and 59.6±8.6(range, 39-71) for NTG patients. All patients underwent complete ophthalmic examination, achromatic automated perimetry (AAP), scanning laser ophthalmoscopy (SLO), scanning laser polarimetry (SLP), optical coherence tomography (OCT) and Heidelberg retinal tomography (HRT). All patients had glaucomatous optic nerve damage and abnormal AAP. Results There were no differences in mean deviation on AAP between NTG and HTG eyes (P=0.37), while the corrected pattern standard deviation was larger in NTG than in HTG eyes (P=0.014). Cup∶disc area ratios in global (P=0.03) and three sectors (Plt;0.05) except nasal sector were significantly larger in the NTG group, whereas rim area in global (P=0.03) and three sectors (Plt;0.05) except nasal quadrant obtained by SLO were smaller in NTG than in HTG eyes. The other numerical parameters obtained by three imaging technologies could not detect differences in the optic disc or RNFL anatomy between the two groups. Conclusions Cup∶disc area ratio was larger in patients with NTG than in those with HTG, whereas significant thinning of rim was associated with NTG eyes. The measurement of retinal nerve layer thickness in global and each quadrant was similar between two groups. More focal or segmental analysis of the data contained within SLO, SLP and OCT images are needed to detect localized differences in eyes with varying levels of IOP. (Chin J Ocul Fundus Dis, 2002, 18: 109-112)
ObjectiveTo investigate the effects of transforming growth factor-β (TGF-β) in choroidal neovascularization (CNV) induced by laser in mice. Methods Eighty male C57BL/6J mice at the age of 6-8 weeks old were randomly divided into the normal control, photocoagulation model, photocoagulation with phosphate buffered saline (PBS control group) and photocoagulation with TGF-β receptor inhibitor groups (TGF-β receptor inhibitor group), twenty mice of each group. Fundus argon laser photocoagulation was performed in the photocoagulation model group, PBS control group and TGF-β receptor inhibitor group to induce CNV. One week, two, three and four weeks after the laser procedure, fundus fluorescein angiography (FFA) was carried out in the normal control or photocoagulation model groups to observe CNV formation dynamically. Western blot was used to analyze the expressions of TGF-β in the retina from the mice of normal control or photocoagulation model groups, and VEGF or TNF-α in the retina of normal control, PBS control or TGF-β receptor inhibitor groups. The CNV areas of each group were evaluated by using fluorescein stain on retinal pigment epithelium (RPE)/choroid flat mounts after two weeks of photocoagulation. ResultsThe FFA results showed the retinal vessels centered on the optic disc and arranged radially, while the choroidal vascular present network distribution in the normal control mice. Significant leakage of fluorescein showed discoid strong fluorophore in photocoagulation sites of retina at one week after photocoagulation. The quantitative analysis results of Western blot demonstrated that the TGF-β protein expression levels in retina of photocoagulation model mice gradually increased with time passing. The protein expression levels of TGF-β were significant differences in the photocoagulation model group comparing with the normal control group (F=13.042, P < 0.05). The protein expression levels of TNF-α (F=14.721, 17.509) and VEGF (F=18.890, 11.251) increased significantly in retina of PBS control or TGF-β receptor inhibitor groups when compared with that of normal control group at one week, two, three and four weeks after photocoagulation, and the differences were both statistically significant (P < 0.05). Compared with PBS control group, the protein levels of TNF-α and VEGF in retina from TGF-β receptor inhibitor group were significantly reduced, the differences was statistically significant (F=21.321, 16.160, P < 0.05). Two weeks after laser photocoagulation, a distinct reduction in CNV lesion size in the TGF-β receptor inhibitor group mice when compared to PBS or normal control groups, the differences was statically significant (F=4.482, P < 0.05). ConclusionTGF-β may promote CNV formation by up-regulating both TNF-α and VEGF protein expressions, the application of its specific inhibitor is able to reduce CNV progression.
Objective To investigate the features of optic disc formation and retinal nerve fiber layer(RNFL) changes in primary open-angle glaucoma with myopia (M-POAG). Methods On 63 eyes of 38 patients with M-POAG were imaged of the fundus,and were evaluated with the microcomputer image analyser,and were compared with the simple POAG (S-POAG) eyes. Results Variant features of the optic disc and RNFL atrophy were found in this M-POAG eyes.The shapes of the optic disc were revealed to be vertically or horizontally oval,obliquely inserted and irregular,the color of the most of optic disc was pallor.The pattern of glaucomatous cupping was saucer-like (28.6%),vertical (25.4%),oblique (23.8%),pot-like (9.5%),and focally or concentrically cupped.The quotient of the neuroretinal rim area and horizontal C/D ratio were significantly lower than those in S-POAG eyes (Plt;0.05,Plt;0.001).The focal point of the optic disc excavtions tended to be inferior.Most of the incidence in the focal atrophy of RNFL was located inferiorly,and the diffuse atrophy of RNFL was correlated positively with middle or late high-myopia POAG eyes (P＜0.005). Conclusion The variant features of the optic discs,glaucomatous cupping and RNFL atrophy formation in M-POAG eyes found in this series might be helpful in clinical diagnosis. (Chin J Ocul Fundus Dis,2000,16:81-84)
ObjectiveTo observe the effects of angiostatin on the activity of extra-cellular signal-regulated protein kinase (ERK) of retinal microvascular endothelial cells of mice.MethodsAngiostatin was separated and purified by l-lysine sepharose 4B from human plasma. The primary retinal microvascular endothelial cells were divided into 4 groups: the control group, vascular endothelial growth factor (VEGF) 10 ng/ml group, angiostatin 130 μg/ml group, and VEGF (10 ng/ml) + angiostatin (130 μg/ml) group. The expression of ERK1 was assayed by Westernblotting method 1, 2, 5, 10, 15, and 30 minutes after the treatment of angiostatin.ResultsCompared with the control group, the expression of ERK-1 reduced 1 minute after treatment, reduced markedly after 10 minutes. After 30 minutes, no differences of the expression of ERK were seen between the control group and angiostatin group. The activation of ERK-1 of retinal microvascular endothelial cells occurred after stimulated by VEGF, and at the pitch at the peak after 5 minutes. The level of ERK in VEGF group increased 210% than that in the control (P＜0.05). After 30 minutes, no significant difference of the level of ERK between VEGF and the control group. And because of angiostatin, the expression of ERK-1 decreased 11.9%(1 minute)、17.9%(2 minutes)、38.7%(5 minutes)、49.3%(10 minutes) （P＜0.05）、27.9%(15 minutes)、1.12%(30 minutes) respectively.ConclusionsAngiostatin can effectively block the signal path through which VEGF transmits from outside of the cell to cellular nuclei. (Chin J Ocul Fundus Dis, 2005,21:170-173)
Objective To observe whether theograde axial flow of retinal ganglion cells (RGC) in diabetic rats at the early stage was damaged. Methods Diabetic model was induced by streptozotocin in 6 adult male Sprague-Dawley (SD)rats. Fluorogold (FG) was injected to the superior colliculi 4 weeks later.Streched preparation of retina was made 12 and 72 hours after the injection, and was stained after photographed by fluorescent microscope. The proportion of RGC with different sizes labeled by FG was calculated. Other 6 normal adult male SD rats were in the control group. Results Twelve hours after injection with FG, there was no difference of the total number of RGC in experimental and control group, but the ratio of small RGC was lower in experimental group than that in the control group; 72 hours after injection with FG, The number of RGC, especially the small RGC, decreased obviously in experimental group compared with the control group. Conclusion The speed of the retrograde axial flow of RGC in diabetic rats at the early stage is affected, and the small RGC are damageable. (Chin J Ocul Fundus Dis, 2006, 22: 4-6)
The pathogenesis of diabetic retinopathy (DR) is more complex. For the upstream of traditional pathogenesis, to looking for unifying mechanism theory which proposed in foundation of common promoters and the latest view of DR may be the result of chronic inflammation. Both of them provide the basic and clinical theraby of DR with new direction. Therefore, there are many related issues still needs to intensive study. （Chin J Ocul Fundus Dis，2008，24：237-239）
ObjectiveTo evaluate the effect of form deprivation myopia on optic nerve head and retinal morphology in guinea pigs using optical coherence tomography (OCT). MethodsTwenty guinea pigs aged from 4 to 5 weeks were chosen and randomly divided into the experimental group and control group, with 10 guinea pigs in each group. Form deprivation myopia was established for the right eyes of guinea pigs in experimental group for 4 weeks. The guinea pigs of control group were not intervened. Before and 4 weeks after form deprivation, refraction was measured by retinoscopy after cycloplegia; the axial length was measured by A-scan ultrasound; retinal nerve fiber layer (RNFL) thickness, optic nerve head and retinal morphology of guinea pigs were analyzed using OCT. ResultsBefore form deprivation, there were no statistically significant differences in spherical equivalent, axial length, RNFL thickness, disc edge area, optic disc area, average cup disc ratio, vertical cup disc ratio, cup volume, retinal thickness, or retinal volume between the experimental group and control group of guinea pig (P > 0.05). After 4 weeks of form deprivation, RNFL thickness of (64.9±17.7) μm in guinea pigs in experimental group was thinner compared to (97.9±25.1) μm in control group (t=-2.845, P=0.015). Retinal thickness of (142.7±3.4) μm in guinea pigs in experimental group was thicker compared to (138.4±3.5) μm in control group (t=2.338, P=0.038). There were no significant differences in disc edge area, optic disc area, average cup disc ratio, vertical cup disc ratio, cup volume or retinal volume between groups (P > 0.05). There were statistically significant differences in spherical equivalent, axial length, RNFL thickness, vertical cup to disc ratio cup volume, and retinal thickness between after and before form deprivation in the right eye of guinea pigs in the experimental groups (t=46.001, -50.119, 5.385, 3.447, -2.814, -8.911; P < 0.05), while there were no statistically significant differences in disc edge area, optic disc area, average cup disc ratio, or retinal volume (P > 0.05). ConclusionForm deprivation myopia has an effect on RNFL and retinal thickness.
ObjectiveTo investigate the effects and mechanisms of G protein-coupled receptor 91 (GPR91) on blood-retinal barrier (BRB) in diabetic rats. MethodsA lentiviral vector of shRNA targeting rat GPR91 and scrambled shRNA were constructed. Healthy male Sprague-Dawley (SD) rats were selected in this study. The 60 rats were randomized into 4 groups and treated as follows:(1) control group (Group A, n=15), the rats received injections of an equal volume of 0.1% citrate buffer; (2) streptozocin (STZ) group (Group B, n=15), the rats received injections of STZ; (3) LV.shScrambled group (Group C, n=15), diabetic rats received an intravitreal injection of 1 μl 1×108 TU/ml scrambled shRNA lentiviral particles at 2 weeks after the induction of diabetes; (4) LV.shGPR91 group (Group D, n=15), diabetic rats received an intravitreal injection of 1 μl 1×108 TU/ml pGCSIL-GFP-shGPR91 lentiviral particles. At 12 weeks after intravitreal injection, immunohistochemistry and Western blot were used to assess the expression of GPR91, p-extracellular signal-regulated kinase(ERK)1/2, t-ERK1/2, p-Jun N-terminal kinase (JNK), t-JNK, p-p38 mitogen-activated protein kinase (MAPK) and t-p38 MAPK. Haematoxylin and eosin (HE) staining and Evans blue dye were used to assess the structure and function of the retinal vessel. Immunohistochemistry enzyme-linked immunosorbent assay (ELISA) was used to test the protein level of VEGF. ResultsImmunohistochemistry staining showed that GPR91 was predominantly localized to the cell bodies of the ganglion cell layer. Western blot showed that GPR91 expression in Group D decreased significantly compared with Group C (F=39.31, P < 0.01). HE staining showed that the retina tissue in Group B and C developed telangiectatic vessels in the inner layer of retina, while the telangiectatic vessels attenuated in Group D. It was also demonstrated in Evans blue dye that the microvascular leakage in Group D decreased by (33.8±4.11)% compared with Group C and there was significant difference (F=30.35, P < 0.05). The results of ELISA showed the VEGF secretion of Group B and C increased compared with Group A and the VEGF expression in Group D was significantly down regulated after silencing GPR91 gene (F=253.15, P < 0.05).The results of Western blot indicated that compared with Group A, the expressions of p-ERK1/2, p-JNK and p-p38 MAPK were significantly upregulated (q=6.38, 2.94, 3.45;P < 0.05). Meanwhile, the activation of ERK1/2 was inhibited by GPR91 shRNA and the difference was statistically significant (F=22.50, P < 0.05). ConclusionsThe intravitreal injection of GPR91 shRNA attenuated the leakage of BRB in diabetic rats. GPR91 regulated the VEGF release and the leakage of BRB possibly through the ERK1/2 signaling pathway.
Purpose To investigate retinoic acid (RA) induced apoptosis in retinal pigment epithelial (RPE) cells. Methods 10-5、10-6、10-7 mol/L were added to cultured PRE cells.Aridine orange fluorescence and TdT-mediated dUTP nick end labelling(TUNEL) techniques were used to observe apoptotic changes. Resultss 10-5、10-6、10-7 mol/L RA induced apoptosis in RPE cells.Cell shringkage,chromatin condensation and nuclear DNA fragmentation of RPE cells were observed by TUNEL technique.When 10-7、10-6、10-5mol/L RA treated RPE cells for 5 days,apoptotic index(AI)was 36.9%、4409% and 61.4% respectively,and 48.0%、59.9%、74.2% for 6 days.At the same concentration of RA,AI increased when time prolonged．At the same day,AI increased when the concentration of RA rose.There was significant difference in the results(Plt;0.05). Conclusion Our results showed that RA-induced apoptosis in RPE cells was detected with a good dose and time response. (Chin J Ocul Fundus Dis,1998,14:153-155)