Objective To investigate the effect of the damage and functional change of vascular endothelial cells (VEC) on diabetic retinopathy(DR). Methods Circulating endothelial cell (CEC) number and plasma endothelin(ET) level were measured in 18 normal control subjects and 55 patients with diabetes mellitus (DM) consisting of 20 cases of DM with out retinopathy,20 cases of DM with-background diabetic retinopathy and 15 cases of DM with proliferative diabetic retinopathy. Results CEC number and plasma ET level in DM were significantly higher than those in normal subjects(Plt;0.001)respectively.With the progression of DR,CEC number was significantly elevated and plasma ET level was gradually elevated.There was significant positive correlation between CEC number and plasma ET level (r=0.738,Plt;0.001,n=55). Conclusion VEC damage and elevated plasma ET level induced by VEC damage may play an important role in the development and progression of DR. (Chin J Ocul Fundus Dis,2000,16:166-168)
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 cultivate human retinal capillary endothelial cells (HRECs) and establish two-dimensional model of human retinal vessels in vitro. Methods In a fibronectincoated raising pound, HRECs were cultured by non-serum human-endothelial-cells substrate and two-dimensional model of human retinal vessels was established. Horseradish peroxidase was used to detect the permeability. Some of the vascular models were cultivated with 5 ng/ml vascular endothelial growth factor (VEGF), whose changes of permeability was compared with which of the models without cultivation with VEGF. The effect of VEGF on vascular permeability was observed. Results Meshy vascular structure came into being due to the confluent HRECs after 2 to 4 days. Comparatively complete two-dimensional vascular model after about 6 days. VEGF increased vascular permeability and promoted the formation of blood vessels. Conclusion HRECs can be cultivated successfully with human-endothelial-cells substrate; standard retinal two-dimensional vascular model in vitro can be established by using cellular raising pound and non-serum human-endothelial-cells substrate. (Chin J Ocul Fundus Dis, 2006, 22: 110-112)
Purpose To investigate the effects of human vitreous fluid on proliferation of cultured human retinal pigment epithelial (RPE) cells and vascular endothelial cell lines(VEC304). Methods Human RPE cells and VEC304 were cultured and treated in different human vitreous-conditioned medium (VCM) with or without serum, vitreous volume concentrations of VCM were 1∶8, 1∶4 and 1∶2. Cells proliferation was assayed by tetrazolium (MTT) colorimetry at the 2nd, 4th and 6th day respectively. Results In the presence of serum, 1∶4, 1∶2 VCM had a significantly stimulative effect on RPE cells proliferation compared with control group at the 2nd, 4th, and 6th day retrospectively (P＜0.01), but exerted a bly inhibitory effect on VEC304 proliferation compared with control group at the 2nd, 4th, and 6th day retrospectively (Plt;0.05). In the absence of serum, only 1∶2 VCM had a stimulative effect on RPE cells growth compared with control group at the 2nd day (P＜0.05) and obviously at the 4th and 6th day respectively (P＜0.01). Conclusion Human vitreous fluid influences human RPE cells and VEC304 growth in vitro. This result suggests that vitreous may play different role in proliferative vitreoretinopathy and intraocular neovascular disease. (Chin J Ocul Fundus Dis, 2002, 18: 140-142)
Objective To detect the apoptosis of vascular endothelial cells and retinal pigment epithelial (RPE) cells in vitro induced by verteporfin-photodynamic therapy. Methods Cultured vascular endothelial cells and human RPE cells were incubated with verteporfin at a concentration of 1.0 mu;g/ml which was equivalent to the initial plasma level of verteporfin in clinical therapy. Each kind of cells were divided into 6 groups according to different time of incubation: 0, 5, 15, 30, 60, and 120 minutes group. After incubated, the cells were illuminated by the laser light with the maximum wavelength of absorption of verteporfin (wavelength: 689 nm, power density: 600 mW/cm2) with the power of 2.4 J/cm 2for 83 seconds. The percentage of cellular apoptosis was measured by flow cytometry 3 hours after PDT, and the measurement was repeated thrice. Results The proportion of cellular apoptosis 3 hours after PDT were 0.01plusmn;0.01, 0.25plusmn;0.02, 0.32plusmn;0.02, 0.41plusmn;0.04, 0.49plusmn;0.03 and 0.61plusmn;0.02, respectively in 0-120 minutes group of vascular endothelial cells; and 0.02plusmn;0.01, 0.22plusmn;0.01, 0.31plusmn;0.02, 0.38plusmn;0.03, 0.47plusmn;0.05 and 0.58plusmn;0.03 respectively in 0-120 minutes group of RPE cells. The proportion of cellular apoptosis of both kinds of the cells increased as the incubation time was prolonged. There was no significant difference of the percentage of cellular apoptosis between the accordant time groups in the two kinds of cells (P＞0.05). Conclusions Cellular apoptosis can be quickly induced by verteporfin-PDT both in human vascular endothelial cells and RPE cells; under the same condition in vitro, PDT has no obvious selection for the apoptosis of the two kinds of cells. (Chin J Ocul Fundus Dis, 2006, 22: 253-255)
Objective To observe apoptotic and proliferative characteristics of the retinal vascular end othelial cells (RVECs) of the 1～16 weeks diabetic rats and p53 and bcl-2 expressions of the rats,in order to probe the pathogenic mechanism of diabetic retinopathy(DR). Methods Models of diabetic Wistar rats were made by alloxan venous injection.The retinal blood vessels were filled by ink,the wholemounts and paraffin-embedded sections of the retinas were made,TUNEL staining and Immunohistochemical ABC staining were used,and light microscopy was taken,in succession. Results Apoptosis of the RVECs was not found.Compared with control group,the morphologic features of the RVECs and the structure of the retinal blood vessels remained unchanged.In the period from the 10th to the 16th week,the immunohistochemical stain of PCNA,BrdU,p53,and bcl-2 for RVECs revealed positive results,but there was no any sign of the RVECs stacking and proliferating or new blood vessels forming in the retinas.In control group,the reaction of immunological stain of the aforementioned parameters was negative. Conclusions No accelerated apoptosis and proliferation of the RVECs in the 1～16 week diabetic rats happen after alloxan injection.Almost all of the RVECs were stimulated to enter the cell cycle in the 10th week.Expression of p53 and bcl-2 might play an important role in stabilizing the RVECs in early stage of diabetes. (Chin J Ocul Fundus Dis, 1999, 15: 157-159)
PURPOSE:To investigate the content of vascular endothelial growth factor (VEGF)in vitreous of patients with retinal vascula'r proliferative diseases. METHODS:The concentration of VEGF in undiluted vitreous samples from patients with retina vein occlusion (RVO) (n=7),Eales disease (n=7)and controls (n=7) was measured by enzyme linked immunosorbent assay (EL1SA). RESULTS:The levels of vitreous VEGF were significantly higher 13 folds in patients with RVO(4.67plusmn;3.38)ng/ml and 5 folds in patients with Eales disease(1.79plusmn;0.44)ng/ml than in controls (0.35plusmn;0.15)ng/ml separately(P＜0. 01). CONCLUSIONS:VEGF might play a part in mediating the neovascularization of retinal vascular diseases. （Chin J Ocul Fundus Dis,1997,13:171-173）
Purpose To investigate the status of proliferation and activation of vascular endothelial cells in preretinal neovascular membranes from patients with insulin dependent diabetetes mellitus(IDDM)by means of immunohistochemical techniques. Methods Status of vascular endothelial cells in 18 preretinal neovascular membranes from 18 patients with IDDM was studied by double-immunofluorescence technique and the alkaline phosphataes-anti-alkaline phosphatase(APAAP)technique and compared the findings with the main clinical features of the patients. Results Of 18 vascularized membranes,16(88.9%)contained proliferating endothelial cells (positive for proliferating vascular endothelial cell marker EN 7/44) and 14 (77.8%) were positive for endothelial cell activation marker anti-VCAM-1;furthermore,by using a double staining technique,we found that in 14 of the 16 cases(87.5%) the proliferating vascular endothelial cells were activated (expressing VCAM-1). Conclusion The proliferation and activation of the vascular endothelial cells of the newly formed vessels in preretinal neovascular membranes suggests the significance of the vascular endothelial cells in the pathophysiology and the progress of proliferative diabetic retinopathy. (Chin J Ocul Fundus Dis,1998,14:141-143)
Purpose To estabalish a quantifying model of retinal neovascularization suitable for the study of pathogenesis and therapeutic intervention for the retinal neovascularization． Methods Sixteen one-week-old C57BL/6 mice were exposed to 75% oxygen for 5 days and then to room air and 16 mice of the same age kept in room air as controls.Ink-perfused retinal flatmount was examined to assess the oxygen-induced changes of retinal vessels.The proliferated neovascular response was quantitated by counting the nuclei of endothelial cells of new vessels extending from the retina into the vitreous in 6 mu;m sagittal cross sections． VEGF and bFGF were determined on the cross-sections after immunohistochemcal stain. Results Constriction and closure of the blood vessels were found under the hyperoxia condition,and dilation and proliferation were found under the relatively hypoxia status.There was a mean of 24 neovascular nuclei per cross-section in the oxygen-treated retina and less than 1 nucleus in the control group (P＜0.001).VEGF stain was found ber in the inner retinal layer of oxygen-treated mouse than in that of the controls. Conclusion The quantifying model of retinal neovascularization may fascilitate the further researches of medical intervention and pathogenesis of retinal neovacularization. (Chin J Ocul Fundus Dis，2000，16：213-284)
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)