苦参碱对大鼠角膜新生血管的抑制作用

目的观察苦参碱对大鼠角膜烧伤后新生血管生成的抑制作用。方法选取Wistar大鼠32只,建立碱烧伤角膜新生血管模型,随机分成对照组和3个不同剂量的苦参碱实验组,每组8只(16眼)。模型建立后,实验组大鼠在结膜下注射不同剂量的苦参碱(0.2mg、0.4mg、0.8mg),对照组注射生理盐水,在裂隙灯下动态观察大鼠角膜新生血管生长情况并计算角膜新生血管的面积,观察周期为21d。于造模后4d、7d、14d、21d取不同剂量的苦参碱实验组大鼠角膜进行组织病理学检测,采集各组大鼠的角膜标本,用免疫组化法检测角膜组织中血管内皮生长因子(vascular endothelial growth factor,VEGF)的表达,计算其平均光密度值;采用RT-PCR方法检测各组大鼠角膜组织中VEGF mRNA的表达。结果碱烧伤后4d、7d、14d、21d,与对照组相比,各实验组大鼠新生血管面积明显减少,差异均有显著统计学意义(P<0.01);造模后14d时,不同剂量的苦参碱实验组新生血管密度计数(17.83±2.32、11.00±2.37、10.87±2.41)明显低于对照组(21.11±2.14)(P<0.05);各实验组角膜VEGF的平均光密度值均小于对照组,差异有统计学意义(P<0.05);各实验组VEGF mRNA水平与对照组相比也显著下降(P<0.05)。结论结膜下注射苦参碱对大鼠角膜碱烧伤后的新生血管生长有抑制作用。

Inhibitive effect of Matrine on corneal neovascularization

Objective To investigate the inhibitive effect of Matrine on corneal neovascularization after alkali burn.Methods Thirty-two Wistar rats were employed to establish corneal neovascularization model by alkali burn,which were divided into control group and three different doses of experimental groups randomly,8 cases(16 eyes) in each group.After the models were successfully established,different doses of Matrine(0.2 mg,0.4 mg,0.8 mg) were subconjunctival injected in experimental group,while saline were injected in control group.The processes of corneal neovascularization were dynamically observed by slit lamp for 21 days and growth areas of new blood vessels were calculated.The histopathology of cornea was examined in experimental group at 4 days,7 days,14 days and 21 days after modeling,and the corneal samples were collected,immunohistochemistry method was employed to measure the level of vascular endothelial growth factor(VEGF) in each group,the averaged OD value was calculated,VEGF mRNA in corneal tissue were simultaneously examined by RT-PCR in each group.Results At 4 days,7 days,14 days and 21 days after corneal neovascularization model were established,the growth areas of new blood vessels in all experimental group rats were significantly lower than that in control group rats,there were significant differences(both P<0.01).At 14 days,the new vessels number in experimental groups with different dose of Matrine were 17.83±2.32,11.00±2.37 and 10.87±2.41,which were obviously lower than that in control group(21.11±2.14),there were statistical differences(both P<0.05).In each time point,the averaged OD value in all experimental groups were significantly lower than that in control group,there were statistical differences(both P<0.05);VEGF mRNA expression levels in all experimental groups were also obviously lower than that in control group(both P<0.05).Conclusion Subconjunctival injection of Matrine has inhibitive effect on corneal neovascularization induced by alkali burn.