Objective Methods Ninety male Wister rats were randomly divided into normal control group, diabetic group and FTY720 group, thirty rats in each group. Diabetes was induced by giving a single intraperitoneal injection of streptozocin. FTY720 group was administered with FTY720 at a dose of 0.3 mg/kg by oral gavage daily for 3 months after establishment of diabetes. All rats were used for experiments following intervention for 3 months in FTY720 group. Immunohistochemical staining was used to observe the expression and distribution of intercellular adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1), and the positive cells were counted. Real-time reverse transcription PCR was used to measure mRNA expression of ICAM-1 and VCAM-1. Fluorescein isothiocyanate-Concanavalin A perfusion was used to detect retinal leukocytes adhesion. Evans blue (EB) perfusion was used to analyze retinal vascular permeability. Immunofluorescence staining was used to detect retinal inflammatory cells infiltration. Results In diabetic group, both ICAM-1(t=12.81) and VCAM-1 (t=11.75) positive cells as well as their mRNA expression (t=16.14, 9.59) were increased compared with normal control group, with statistical significance (P < 0.05). In FTY720 group, both ICAM-1(t=-9.93) and VCAM-1 (t=-6.61) positive cells as well as their mRNA expression (t=-15.28, -6.10) were decreased compared with diabetic group, with statistical significance (P < 0.05). Retinal leukocytes adhesion (t=16.32) and EB permeability (t=17.83) were increased in diabetic group compared with normal control group, while they were decreased in FTY720 group compared with diabetic group(t=-9.93, -11.82),with statistical significance (P < 0.05). There were many CD45 positive leukocytes infiltration in retina of diabetic group, including CD11b positive macrophage/activated microglia, while both of them were little in FTY720 group. Conclusions FTY720 can decrease retinal leukocytes adhesion, reduce retinal vascular permeability and inflammatory cells infiltration, which is associated with down-regulation of ICAM-1 and VCAM-1.
Objective To verifying the characteristics of optical coherence tomography(OCT) in exudative age-related macular degeneration (AMD). Methods The patients being investigated in this series included 16 cases (19 eyes) of exudative age-related macular degeneration diagnosed by FFA and OCT examinations, among them 4 cases (6 eyes) were examined with ICGA. The color photographs of ocular fundi, FFA, ICGA and OCT were investigated by contrasting each other. Results As compared with the FFA and ICGA examinations, the characteristic findings found in OCT in patients with exudative AMD in this series were as the following:①serous detachment of neurosensory epithelium in 11 eyes,②retinal hemorrhage in 2 eyes,③serous detachment of retinal pigment epithelium in 5 eyes,④hemorrhagic detachment of retinal pigment epithelium in 10 eyes,⑤disciform scar in 4 eyes,⑥fibrovascular pigment epithelial detachment and occult CNV in 12 eyes. Conclusion OCT can supply a comprehensive survey of exudative AMD, in making the diagnosis as an important complementary examination of FFA and ICGA. (Chin J Ocul Fundus Dis,2000,16:220-223)
Purpose To study changes of cell cycle of vascular endothelial cell in non-proliferative diabetic retinopathy. Methods Alloxan induced Wistar-rats were employed and immunohistochemistry,Western blotting methods were used. Results The vascular endothelial cells of retinas of 8～20 weeks diabetic rats were observe to be cyclinD1,cyclinD3,cyclinB1,p21 and p27 positive stained with light and electronmicroscopies.CyclinE immuno-stained vascular endothelial cells was observed occasionally.Meanwhile,the evidences of morphologic changes of the vascular en dothelial cells were proved:less plasma,thinner cell,more bubble organelles than those of controls.But,the ultra-structures of pericytes and other type of retinal cells did not change and they also immunostain negative.Komas blue and Western blotting methods also proved that the vascular endothelial cells of retina of 20th week diabetic rats expressed cyclinD1,cyclinB1,p21 and p27 protein. Conclusion Glucose induced retinal vascular endothelial cells of 8～20th weeks diabetic rats enter cell cycle and were arrested at G1/S restriction point.This study also suggested that retinal vascular endothelial cells may possess the ability to resist glucose damage and mechanism of selfstability during very early stage of diabetes. (Chin J Ocul Fundus Dis,2000,16:173-176)
Objective To investigate the role of adenosine A2A receptor plays in retinal pathological neovascularization in mice. Methods A total of 202 mice were divided into room-air group (n=66) and oxygen induced retinopathy (OIR) group (n=136). Among room-air group, there were 18 A2A knock-out (KO) mice (KO subgroup) and 24 C57BL/6 mice as wide type (wide type subgroup). OIR group were divided into OIR control subgroup (n=48), A2A-OIR subgroup (n=24) and Caffeine-OIR subgroup (n=64). The retinal neovascularization of OIR group was induced by oxygen. The pathological neovascularization was determined by retinal sections. Fluorescent quantitative polymerase chain reaction (PCR) was used to measure the mRNA expression of A2A and vascular endothelial growth factor (VEGF). 0.1, 0.3, 1.0 g/L Caffeine was dissolve in drinking water of lactating females in Caffeine-OIR subgroup, non-perfusion areas of retina in mice at the age of 0 - 17, 0 - 7, 7- 17, 7-12, and 12- 17 days were analyzed in different dosage and when the dosage as 1.0 g/L. Results Compared with OIR control subgroup, the retinal non-perfusion areas and the numbers of endothelial cell nuclei breaking through the internal limiting membrane in A2A- OIR subgroup were reduced significantly (t=7.694, 7.747;P＜0.001). Compared with wide type subgroup, the level of A2A and VEGF mRNA in OIR control subgroup increased significantly (t=4.036, 2.230;P＜0.05). Compared with OIR control subgroup, the level of VEGF mRNA in A2A- OIR subgroup decreased significantly (t=3.122,P＜0.01). Compared with OIR control subgroup, the retinal non-perfusion areas in mice at the dosage of 0.1 and 1.0 g/L (t=2.397, 4.533) and at the age of 0 -17, 0 -7 days when the dosage as 1.0 g/L (t=4.070, 2.399) were reduced significantly (P＜0.05). Conclusions The expression of adenosine A2A receptor increases in oxygen-induced retinal pathological neovascularization. Adenosine A2A receptor may regulate the expression of VEGF. A2A receptor inactivation can inhibit oxygen-induced retinal pathological neovascularization.
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.