血管内皮生长因子与大鼠角膜移植术后新生血管增生关系的实验研究

Experiment on the relationship between vascular endothelial growth factor and neovascularization resulting from penetrating keratoplasty in rat

目的 :观察血管内皮生长因子 (vascularendothelialgrowthfactor,VEGF)在大鼠角膜移植术后不同时间点的表达及与角膜新生血管 (CNV)生长之间的关系。方法 :利用免疫组化方法观察同种异体大鼠角膜移植术后不同时间点VEGF的表达。结果 :角膜移植术后 ,VEGF组CNV生长面积与其它各组差异有高度显著性 (P <0 0 0 1 ) ,生长时间提前 ,高峰期持续时间长 ,VEGF表达明显增强。白介素 1受体拮抗剂 (IL 1ra)和地塞米松组CNV出现的时间迟 ,生长较慢 ,高峰持续时间短 ,约 3～ 4周时就开始减退 ,经统计学比较与其它各组差异有高度显著性 (P <0 0 1 ) ,VEGF表达较弱。生理盐水组和对照组CNV在角膜移植术后出现的时间基本相同 ,生长速度和CNV面积经统计学比较差异无显著性 (P >0 0 5) ,但与地塞米松组和IL 1ra组比较差异有显著性 (P <0 0 5) ,VEGF呈强表达。结论 :VEGF的表达和角膜新生血管增生呈正相关。外源性VEGF可促进角膜新生血管的增生 ;VEGF在角膜新生血管性疾病中起很重要的作用。IL 1ra抑制由IL 1引起的角膜炎性反应 ,使VEGF的表达减低 ,从而抑制了CNV。

Objective:To observe the relationship between the expressions of the vascular endothelial growth factor(VEGF)and the growth of corneal neovascularization at different periods after allograft in rats,and VEGF’s effect on accelerrating the growth of corneal neovascularization(CNV).Methods:With immuno-histochemical analysis,the relationship between the expressions of the vascular endothelial growth factor(VEGF)and the growth of CNV is observed.Results:The experiment shows that VEGF could marketly accelerate the growth of CNV.The CNV in the VEGF group not only occures earlier,but also grows faster reaching its peak than other groups.It is significant statistically with other groups( P <0 001).Immuno-histochemistry shows that the high expression of VEGF in the cornea stroma.In IL-1ra and dexamethason groups CNV occures later and grows slowly.It is significant statistically with other groups( P <0 01).Result of immunohis- tochemistry shows that expression of VEGF is lower than those in other groups.The CNV under NS group reaches its peak within a short time,lasts longer and grows faster than control group and there is no difference statistically ( P >0 05).The expression of VEGF is high in two groups.Conclusion:The expressions of VEGF are in direct proportion to the growth of CNV.External VEGF can accelerate the growth of corneal neovascularization while IL-Lra may inhibit the corneal inflammatory reaction and the growth of CNV.Dexamethason inhibits the growth of CNV by inhibiting the corneal inflammatory reaction.IL-lra and Dexamethason decrease the expression of VEGF.