苏拉明对角膜碱烧伤新生血管抑制作用的研究

目的研究苏拉明对碱烧伤角膜新生血管（CNV）及血管内皮生长因子（VEGF）、胰岛素样生长因子-I（IGF—I）的影响。方法新西兰大白兔48只，分为空白组、对照组、苏拉明组3组，每组16只（32只眼）。对照组与治疗组制备角膜碱烧伤模型，术后分别给予氯霉素、8g／L苏拉明滴眼液点眼。分别于术后第1、4、7、14d观察新生血管情况，免疫组织化学法检测VEGF、IGF—I的表达。结果术后第1d各组无新生血管生长。第4、7、14d，空白组未出现新生血管，对照组与治疗组可见CNV，且治疗组比对照组新生血管面积小（P〈0．01）。第1、4、7d，对照组与治疗组VEGF、IGF—I的表达均比空白组升高，差异有统计学意义（P〈0．01），治疗组与对照组相比，差异亦有统计学意义（P〈0．01）。第14d，3个组间比较差异无统计学意义（P〉0．05）。结论VEGF、IGF—I参与CNV形成，苏拉明通过降低角膜上皮中二者的表达，抑制角膜碱烧伤新生血管形成。

Inhibitory effects of suramin on corneal neovascularization after corneal alkali burn

Objective Corneal neovascularization is a main pathological change after corneal alkali burn. It has been determined that vascular endothelial growth factor（VEGF） and insulin-like growth factor-I （IGF- I ） promote the formation of new blood vessel;while suramin can arrest the expression of many cytokins and further inhibit neovascularization. This study was to investigate the influence of suramin on corneal neovascularization（CNV） after alkali burn. Methods The ocular alkali burn model was created by putting the filter of NaOH at the central cornea for 1 min in 36 New Zerland white rabbits. The suramin drops was topically used in 16 models 4 times per day. Chloramphenlcol eye drops was used at the same way in the control group （ 16 rabbits）. The other 16 normal New Zerland white rabbits were as blank control group. The corneal inflammation and CNV area was evaluated and calculated on the 1,4,7,14 days after operation under the slim-lamp. The expressions of VEGF and IGF-I were detected by immunochemistry. The histological change in different groups was examined under the light and transmission electron microscope. Results The flammatory reaction and cornea edame were obviously slight in suramin group compared with Chloramphenlcol under the slim-lamp. The CNV area in suramin group was significantly smaller than that of Chloramphenlcol group in 4,7,14 days after cautery（ P 〈 0. 05 -0. 01 ）. The area density value of VEGF in cornea was obviously reduced in suramin group and Chloramphenlcol group compared with blank control group in 1,4,7 days after cautery （P 〈0.05 - 0.01 ） , and that in suramin group was lower than Chloramphenlcol group in above time points （P 〈 0.01 ）. The area density value of IGF-I in cornea presented the similar outcome in various time after cautery. No obviously changes were found in the expressions of VEGF and IGF- I on the 14th day among 3 groups（P 〉 0.05 ）. The abnormalities of organelle was more obvious in Chloramphenlcol group than the suramin group