Objective To verify the effect of Evans blue dye on determining the retina blood vessel leakage. Methods Male Sprague-Dawley rats were used in this study. The VEGF induced retinal blood vessel leakage was checked with Evans blue dye. Then the bloodretina barrier breakdown of 1 week diabetic animals was quantified with Evans blue.The dye was extracted from retina by formamide and the extraction was checked with spect rophotometer. Evans blue leakage was normalized against wet or dry retina weight. Results The retinal Evans blue content of eyes treated with VEGF was remarkably higher than that of the controls (n=17 ,Plt;0.0001). And the eyes of 1 week diabetic duration animals had more Evans blue dye than that of the normal controls (Plt;0.05). Conclusion Evans blue dye is a sensitive tracer in quantitatively diagnosing the blood retina barrier breakdown. (Chin J Ocul Fundus Dis, 2001,17:221-223)
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)
ObjectiveTo observe the expression of connective tissue growth factor (CTGF) in injured model of retinal pigment epithelial (RPE) cells and the promoting effect of CTGF on migration of RPE cells.MethodsCultured monolayer-confluent human RPE cells were scraped with a trephine and a cotton stick, and set up the injured model of RPE cells with round scraped area. Immunohistochemistry and in situ hybridization(ISH) were used to detect the expression of CTGF protein and mRNA in injured RPE cells at distinct time points after injury. The number of RPE cells migrated to injured area was measured and the effect of CTGF on migration of RPE cells and the effect of dexamethasone (DEX) on the promoting process of CTGF were observed.ResultsThe results of immunohstochemistry and ISH indicated the weak positive expression of CTGF in RPE cells at the edge of scrape 6 hours after injury, and the positive expression increased gradually as time goes by after the injury. Strong positive expression of CTGF in RPE cells at the edge of scrape was found 24 and 48 hours after injury. Rebuilt human CTGF stimulated migration of RPE cells in a dose-depended manner, and DEX significantly inhabited the migration.ConclusionCTGF involves in the procedure of repair of injury of RPE cells, which may play an important role in the pathogenesis of intraocular proliferative diseases such as proliferative vitreoretinaopathy.(Chin J Ocul Fundus Dis, 2005,21:306-309)
Objective To investigate the effects of Hep-A and Hep-B on vascular endothelial growth factor (VEGF)-induced breakdown of blood-retinal barrier. Methods The mice were subcutaneously injected vehicle, Hep-A or Hep-B 10 mg/kg twice a day for 5 days. Then, 1 μl of 10-6mol/L VEGF were intravitreous injected. After 6 hours, 13.7×104Bq/g3H-mannital were injected intraperitoneally. The mice were sacrificed and the retinas, lungs, kidneys were removed and examined for radioactivity. The result were analyzed using SPSS software to calculate and compare retina/lung and etina/kidney leakage ratio among groups of different treatment. Result The retina/lung and retina/kidney leakage ratio were 0.38±0.04 and 0.21±0.03 respectively in normal mice; increased significantly to 1.05±0.11 and 0.46±0.04 respectively in model mice, both Plt;0.01 compared to those in normal mice; decreased to 0.59±0.06 and 0.32±0.03 respectively in mice treated with Hep-A, both Plt;0.01 compared to those in model mice; decreased 0.54±0.04 and 0.35±0.03 in mice treated with Hep-B,both Plt;0.01 compared to those in model mice. Conclusion Hep-A and Hep-B can significantly reduce VEGF-induced breakdown of blood-retinal barrier in mice. Chin J Ocul Fundus Dis,2004,20:352-354)
Purpose To determine the effect of exogenous interleukin-1alpha; (IL-1alpha;) on the retina and its vasculature and VEGF expression in SD rats. Methods IL-1alpha;2.0 ng (20 mu;l) were injected into the vitreous of 8 left eyes of 8 SD rats while steriled PBS were injected into 8 right contralateral eyes of the same rats as control. All eyes were assessed by direct ophthalmoscopy every day and enucleated on the 7 thpostoperative day. Histological examination (hemato xylineosin staining) and immunohistochemical staining with antibody against VEGF antigen were performed, and sections were observed and photographed under light microscopy. Results ①All 8 IL-1alpha; inject ed eyes developed epiretinal membranes and extraretinal neovascularization on the 3 rd postoperative days while none of the 8 control eyes exhibited any a bnormal retinal vascular changes and they were confirmed by HE staining;②Immuno staining identified VEGF express mainly in the inner layer of vessel walls, the epiretinal membranes, the neuroganglional layer and the photoreceptor layer of retina, while the control eyes showed only weak positive staining in the photo receptor layer. Conclusions IL-1alpha; is capable of inducing vitreo retinal neovascularization,and increasing the expression of VEGF in the retina and epiretinal membranes. (Chin J Ocul Fundus Dis, 2001,17:135-137)
Objective To observe the expression of p53, bcl-2 genes, vascular endothelial cell growth factor(VEGF), basic fibroblast growth factor(bFGF), insulin-like growth factor-I (IGF-I), and the receptors of these factors of retinal vascular endothelial cells (VECs) of 1- to 20-week diabetic rats, and the relationship between the expressions and cell cycle arrest.Methods Retinal sections of diabetic rats induced by alloxan were immunohistochemically stained and observed by light microscopy (LM) and electron microscopy (EM). Dot blotting and Western blotting were used to determine the expression of mRNA, proteins of p53 and bcl-2. Results Under LM, immunohistochemical positive expression of p53 and bcl-2 were found on the vessels of ganglion cell layer and inner nuclear layer of retinae of 8- to 20-week diabetic rats; under EM, these substances were observed depositing in VECs. The retinal VECs also expressed VEGF, bFGF, IGF-I and their receptors. There was no positive expression of other cell types in these retinae, all cell types of retinae in control group, or all cells of retinae of diabetic rats with the course of disease of 1 to 6 weeks. The result of dot blotting revealed that retinal tissue of 20-week diabetic rat expressed p53 and bcl-2 mRNA, and the result of Western blotting revealed that they also expressed p53 and bcl-2 proteins. But retinal tissues of control group did not. Positive expression of bax was not found in the retinae in control group or 1- to 20-week diabetic rats. Conclusion p53, bcl-2 may introduce cell cycle arrest of VECs of retinae in 8- to 20-week diabetic rats. High glucose might stimulate the expression of VEGF, bFGF, IGF-I and their receptors, and the growth factors may keep VECs surviving by self-secretion. (Chin J Ocul Fundus Dis,2003,19:29-33)
Objective To observe the effects of high concentr at ion glucose on the calcium-activated potassium channel of rabbits′ retinal Müller cells. Methods The rabbits′retinal Müller cells were cultured in vitro under the condition of high concentration glucose, and identified by immunohistochemical staining and transmission electron microscopy. Patch-clamp technique was used to observe the changes of the calcium-activated potassium channel of retinal Müller cells caused by high concentration glucose at different time.Results High concentration glucose could inhibit the calcium-activated potassium channel of cultured retinal Müller cells in a time-dependent manner. Conclusion High concentration glucose may reduce the biological functions of Müller cells by inhibiting calcium-activated potassium channel. (Chin J Ocul Fundus Dis,2003,19:164-167)
Objective To detect the levels of vascular endoth elial growth factor (VEGF) in aqueous humor and vitreous of patients with neovascular glaucoma (NVG) and infer their possible effect on the development of neovascularization of iris. Methods The concentration of VEGF in 22 samples of ocular fluid of aqueous humor and vitreous respectively obtained from 11 patients with NVG undergone intraocular surgery were measured by using enzyme linked immunosobent assay (ELISA) for quantitative analysis. As control, 12 samples of ocular fluid of 6 patients with macular hole were detected by the same methods. Results The mean [AKx-]plusmn;s VEGF concentrations in aqueous humor and vitreous from patients with NVG were [(1.451plusmn;0.247)、(1.610plusmn;0.125) ng/ml] higher than those in the cotrol group [(0.189plusmn;0.038)、(0.201plusmn;0.055) ng/ml], there was a significant difference between the two groups statistically (t=12.007,Plt;0001;t=26.0 57,Plt;0.001). Conclusion The patients with NVG have significantly increased level of VEGF in ocular fluid, and VEGF might fill the role in mediating active iris neovascularization. (Chin J Ocul Fundus Dis, 2001,17:305-306)
Objective To observe the expression of vascular endothelial growth factor (VEGF) in aqueous humor and vitreous body in eyes with proliferative vitreo-retinal diseases, and to investigate the role of VEGF plays in the pathoge nesis of proliferative vitreo-retinal diseases. Methods The concentration of VEGF in aqueous humor and vitreous body in eyes with proliferative vitreoretinopathy (PVR), retinal vein occlusion (RVO), proliferative diabetic retinopathy (PDR), and neovascular glaucoma (NVG) were measured by double antibodies sandwich enzyme-linked immunosorbent assay (ELISA). Results The concentration of VEGF in aqueous humor and vitreous body in eyes with PVR, RVO, PDR and NVG were obviously higher than that in the control group (Plt;0.05), respectively. Among all of the diseases, the concentration of VEGF in aqueous humor and vitreous body decreased orderly in NVG, PDR, RVO and PVR (Plt;0.05). The concentration of VEGF in vitreous body in eyes with PVR, RVO, PDR and in the control group were much higher than that in aqueous humor in corresponding groups (Plt;0.05). There was a negative correlation between the disease history and content of VEGF in aqueous humor and vitreous body in patients with PVR (r=-0.819, -0.823;Plt;0.05). The disease history positi vely correlated with the concentration of VEGF in aqueous humor and vitreous body in patients with RVO (r=0.913, 0.929;Plt;0.05), and the time of vitreous hemorrhage positively correlated with the concentration of VEGF in aqueous humor and vitreous body in patients with PDR (r=0.905, 0.920;Plt;0.05). Conclusion The concentration of VEGF in aqueous humor and vitreous body in patients with proliferative vitreo-retinal diseases significantly increases, and VEGF may play an important role in the pathoge nesis of proliferative vitreo-retinal diseases. (Chin J Ocul Fundus Dis, 2006, 22: 313-316)
Objective To investigate the relationship between the expression of vascular endothelial growth factor(VEGF)and the retinoblastome(RB)differentiation degree and the infitration capability. Method The VEGF expression in RB tissues of 40 cases was analysed by using LSAB immunohistochemical method. Results The VEGF expression in differentiated RB tissues of 13 cases was markedly lower than that in non-differentiaed RB tissues of 27 cases(P<0.05);The VEGF expression in RB tissues of the optic nerve infiltrated group(14 cases) was significantly higher than of the optic nerve noninfiltrated group(26 cases)(P<0.05). Conclusion The results indicate that the VEGF expression is signficantly related with the differentiation degree and infiltration capability of RB. (Chin J Ocul Fundus Dis, 1999, 15: 238-240)