整合素αvβ3、组织因子及血管内皮细胞生长因子在实验性脉络膜新生血管中的表达

Expression of integrin αvβ3,tissue factor,and vascular endothelial growth factor in experimental choroidal neovascularization

目的:探讨整合素αvβ3、组织因子(tissue factor,TF)及血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)在激光诱导的大鼠脉络膜新生血管(choroidal neovascularization,CNV)组织中的表达。方法:随机选取成年雄性棕色挪威大鼠25只,一眼为实验组,经氩激光(波长532 nm)光凝诱导CNV形成,另一眼为正常对照。分别于光凝后第3,7,14,21及28天随机取5只大鼠,行眼底照相、眼底荧光血管造影(fluorescence fundus angiography,FFA)检查,并取出视网膜,通过免疫组织化学方法检测整合素αvβ3,TF及VEGF在CNV中的表达及相互关系。结果:正常对照组无新生血管生成,无整合素αvβ3和TF的表达,但视网膜神经节细胞层、内核层、色素上皮层、视网膜及脉络膜血管内皮细胞中均有少量VEGF的表达。光凝7 d后,FFA检查发现实验眼光凝区有圆盘状荧光渗漏,表明有新生血管生成。光凝后3 d,光凝区视网膜神经节细胞层、内核层、外核层缺损区、视网膜及脉络膜血管内皮细胞均表达少量的VEGF、整合素αvβ3及TF,随着时间的延长,CNV逐渐形成,VEGF、整合素αvβ3及TF表达水平也逐渐增加(P<0.01),其中整合素αvβ3的表达于第7天达高峰;VEGF的表达于第14天达高峰;TF的表达于第21天达高峰。结论:整合素αvβ3,VEGF及TF分别表达于实验性大鼠CNV形成初期、中期及晚期,其在CNV中表达的顺序对临床选择抗新生血管药物的治疗时间具有十分重要的意义。

Objective To study the expression of vascular endothelial growth factor（VEGF）,integrin αvβ3,and tissue factor（TF） in choroidal neovascularization（CNV）.Methods CNV was induced in 25 Brown Norway（BN） rats by diode laser with 532 nm wave length.In every BN rat,one eye was induced to produce CNV,and the other eye served as the normal control eye.Fundus photography and fundus fluorescein angiography（FFA） were performed just before euthanasia on 3,7,14,21,and 28 d after laser photocoagnlation.The retina was processed for histopathology and immunohischemical analysis to detect the expressions of VEGF,integrin αvβ3,and TF.Results There was no CNV,no expression of intergrin αvβ3 and TF in the normal control eyes.Only a few VEGFs were expressed in the ganglion cell layer of the retina,inner nuclear layer,retinal pigment epithelium,and vascular endothelial cell of the retina and choroid in normal eyes.FFA revealed disc-like leakage of fluorescein 7 days after the photo-coagulation,meaning there was CNV.VEGF,intergrin αvβ3,and TF were all expressed in the ganglion cell layer of the retina,inner nuclear layer,retinal pigment epithelium,and vascular endothelial cell of the retina and choroids 3 days after the photo-coagulation.With the development of CNV,expressions of integrin αvβ3,VEGF,and TF were gradually increasing（P0.01）.The expression of integrin αvβ3 in the retina was at peak on 7th day,VEGF on 14th day,and TF on 21st day.Conclusion Expressions of VEGF,integrin αvβ3,and TF in CNV were found at the early,middle and late stage of CNV formation.It is important to determine the time of anti-neovascularization.