周细胞对大鼠角膜新生血管渗漏的影响

Effects of pericytes on the leakage of rat corneal neovascularization

目的探讨周细胞对大鼠角膜新生血管渗漏的影响。方法建立角膜基质层间植入微粒体诱生新生血管的大鼠模型，数字法随机分配大鼠一只眼为实验组，另一只眼为对照组，实验组植入含有血管内皮细胞生长因子（VEGF）和血小板衍生生长因子-B中和抗体（抗PDGF-B）的微粒体，对照组植入含有VEGF和磷酸盐缓冲液（PBS）的微粒体，术后5d伊文氏兰示踪法检测新生血管渗漏率，角膜称重，d平滑肌激动蛋白抗体（抗α-SMA）和血小板内皮细胞黏附分子抗体（抗CD31）对角膜切片及铺片行双重免疫荧光染色法观察并计算周细胞包裹指数（MPI）。结果实验组MPI为11．3％，角膜重量为（8．96±1．09）mg，新生血管渗漏率为（0．68±0．36）μg·ml-1·mm-2；对照组MPI为56．5％，角膜重量为（7．36±0．56）mg，新生血管渗漏率为（0．24±0．07））μg·ml-1·mm-2，3个指标在实验组和对照组之间比较差异均有统计学意义（PMPI〈0．01，P渗漏率=0．01，P重量=0．01）。结论周细胞具有抑制角膜新生血管渗漏的作用，为新生血管性疾病的抗渗漏治疗提供了理论指导。

Objective To explore the effects of pericytes on the leakage of rat corneal neovascularization （CNV）. Methods CNV was induced by micropocket assay in rats. Two eyes of the same rat were divided randomly into experimental and control groups. The experimental group received the VEGF ＋ anti-PDGF-B pellet while the control group the VEGF ＋ PBS pellet. Corneal samples were excised at Day 5 postoperation. CNV leakage was measured by Evans blue method. Pericyte coverage index （MPI） was applied to quantify the pericyte coverage through double immunofluorescent stain of frozen sections of corneas with CD31 as endothelial and c^-smooth muscle actin （ot-SMA） as pericyte marker. Corneal weight was measured. Results In the control group, MPI was 56. 5%, cornea weight （7.36± 0. 56） mg and CNV permeability rate （0. 24 ±0. 07） μg·ml-1·mm-2. In the experimental group, MPI was 11.3%, cornea weight （8. 96 ± 1.09 ）mg and CNV permeabihty rate （0.68 ± O. 36） μg·ml-1·mm-2 The intergroup difference was statistically significant （ PMPI 〈 0. 01, Ppemleability rate= 0.01 , Pweight = O. 01）. Conclusion Pericytes inhibit the leakage of rat CNV. Such findings may guide the clinical management of hyperpermeability.