ObjectiveTo observe the longterm effect of suramin on the inhibition of proliferation of human retinal pigment epithelial (RPE) cells in vitro. MethodsRPE cells grown in 9 pieces of 96well plate (12 wells each plate) were divided into experimental and control group, with 6 wells in each group. The concentration of 0.1 ml RPE cells in each well is 5×104 cells/ml. After the change of the medium, RPE cells were treated with suramin (250 μg/ml) in experimental group while treated with nothing in the control group. The medium of the 2 groups were changed to the normal medium after 4 days. At the 1st, 2nd, and 4thday after the addition of suramin and at the 1st, 2nd, 3rd, 5th, 6th, 7th, 9th , 11th and 13th day after removing suramin, 1 plate was randomly selected to stop culturing, and the proliferation of RPE cells were detected by methyl thiazolyl tetrazolium (MTT) assay. ResultsUnder reversed microscope, RPE cells in control group were fused completely at the 7th day after inoculation. The extracellular space of RPE cells in experimental groups was larger than that in the control group, and remained unfused at the 13th day after inoculation. The inhibitory rate of proliferation of RPE cells at the first day after treated with suramin was 14.85% and increased to the highest 25.79% at the 4th day. The first day after the suramincontaining media was removed, the inhibitory rate decreased to 12.35%, and then raised gradually to over 20% at the 3rd to 5th day. Finally, the rate drop to 14.71%. ConclusionSuramin has the long-term effect on the inhibition of RPE cells induced by serum, especially the inhibitive effect after the remove of suramin, which indicates the specific double-peak inhibition during the whole process.(Chin J Ocul Fundus Dis, 2005,21:25-27)
Objective To evaluate the effect of vascular endothelial cell growth factor (VEGF) antisense oligodeoxynucleotides (ASODNs) on the expression of VEGF in rats with oxygen-induced retinopathy. Methods Thirty newborn Sprague-Dawley (SD) rats were randomly divided into 3 groups:normal control group, disposal group and non-disposed group, The animal models with oxygen-induced proliferative retinopathy were established by raising the rats in hyperoxic environment. Retrobulbar injection was performed with VEGF ASODNs or normal saline on the rats in 3 groups respectively. The intraocular tissues (all the tissues except the cornea, sclera, and lens) and serum were collected, and the expressions of VEGF were determined by using competitive enzyme immunoassay.Results The expressions of VEGF in intraocular tissues of rats in disposal group were significantly lower than those in non-disposed group (P＜0.05), and there was no statistical difference between the disposal and normal control group (P＞0.05). There was no significant difference of the expressions of VEGF in serum of rats between the disposal and non-disposed group (P＞0.05), which were both lower than those in the normal control group (P＜0.05). Conclusion VEGF ASODNs could significantly inhibit the expression of VEGF in intraocular tissues. (Chin J Ocul Fundus Dis，2003，19：172-174)
The stimulating effects of subretinal fluid (SRF) of 31 patients with rhegnmtoganous retinal detachment (among them 5 are recurrent) on the growth of fihroblasts were investigated. The results demonstrated that all samples of SRF showed stimulating effect in a variable degree.The range of proliferation-stimulating activity was from 86. 7% to 366.7% above the baseline.The stimulating ahility was mainly related to the degree of PVR and may be also related to the extent and clinical course of the detaehrnent. When stimulating rate was S0Y0 ,the dilution multiple of SRF was higher in recurrent patients than that in initiate ( P＜0.01). （Chin J Ocul Fundus Dis,1993,9:11-13）
Proliferative vitreoretinopathy (PVR) is a common complication and major cause of blindness of ocular trauma. Many cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), participate in the process of the pathogenesis of traumatic PVR. VEGF competitively inhibits binding of PDGF to its receptor (PDGFRα), enables indirect activation of PDGFRα by non-PDGF ligands, resulting in reduced p53 expression, cell proliferation and migration, which is a key point in the pathogenesis of traumatic PVR.
Purpose To study the possibility of prevention of proliferative vitreoretinopathy（PVR） by transduction of exogenous gene in vivo． Methods PVR model of rabbits was induced by intravitreal injection of fibroblasts．beta;-galactosidase (lacZ) gene as a reporter gene was transfered into the vitreous of PVR model eyes mediated by retroviral vector, and the expression of the gene in eye tissues was determined ． Gene transfection was done on the 6th day after fibroblasts injection,and the dosage of intravitreal injection of reporter gene was 0．1ml PLXSN/lacZ serum-free supernatant (1．1times;106 cfu/ml)． Results lacZ gene expression was seen in proliferative membranes after gene transfection, and the expression was located maily at the surface of PVR membrane．The reporter gene expression lasted at least more than 30 days．No expression was found in retinal tissues． Conclusions Retrovirus mediated gene can be directionally transducted in PVR membrane,and might possess the feasibility of gene therapy for PVR． (Chin J Ocul Fundus Dis, 2001,17:224-226)
Objective To evaluate the anatomical and functional results of retinotomy in treatment of complicated retinal detachment. Methods Twenty-three eyes were treated with retinectomy during vitrectomy for complicated retinal detachment with proliferative vitreoretinopathy when complete reattachment of retina was not obtained despite careful mambrane peeling. After released the peripheral vitreoretinal contraction or pulled subretinal membranes, perfluorocarbon liquid injection, laser retinopexy and silicone oil tamponade were performed. Retinotomy size ranged from 30-degree to 360-degree (average 132-degree). Results Retinal attachment were obtained in all of the operated eyes at the end of the operation. Silicone oil was removed from 15 eyes (65．0%) within 3～11 months postoperatively. After a minimum follow-up of 6 months, the retinae were completely attached in 17 eyes ( silicone oil was not removed in 4 eyes ) and visual acuity of 0.02 or better was obtained in 11 eye (48．0%). Recurrent retinal detachment occurred in 2 eyes in which the silicone oil had been removed. The major complications were recurrence of the proliferation in 6 eyes (26．0%) and hypotony in 3 eyes (13．0%). Conclusion Retinotomy is beneficial to reattach the retina for eyes with advanced proliferative vitreoretinopathy in seemin gly inoperable cases. (Chin J Ocul Fundus Dis,2001,17:87-89)
Our previous experiments showed limited results of treatment with daunomycin when given at the inflammatory stage of proliferative vitreoretinopathy(PVR)induced by macrophages in rabbits.In the present study,we observed the inhibition of intraocular cellular proliferation in the same model by daunomycin which was injected in a dosage of 5mu;g 6 days after intravitreal macrophage injection,with 3H-thymidine autoradiography.The efficacy of daunomycin was also compared with that of triamcinolone,and combined triamcinlone and daunomycin.The retinal detachment occurred in 33.3%,16.1%,8.3%and 83.3%(P＜0.01) of the eyes treated with daunomycin,triamcinolone,combined drugs and the control groups,respectively.Autoradiography revealed a singnificantly decreased number of labelled nuclei of proliferative cells on days 7 and 14 in daunomycin-treated eyes(compared to controls,18.8plusmn;3.2 vs 35.7plusmn;3.4;52.1plusmn;8.0 vs 81.3plusmn;14.6，P＜0.01,respectively).Significantly decreased numbers of inflammatory cells and labelled cells were also noted in eyes treated with triamcinolone and combined drugs.The results suggest that daunomycin given at the proliferative stage,and triamcionlone given at the inflammatory stage of PVR,or combined drugs can prevent traction retinal detachment. （Chin J Ocul Fundus Dis,1994,10:229-231）