蛹虫草提取物抑制大鼠角膜新生血管的实验研究

目的研究蛹虫草提取物(cordyceps militaris extract,CME)对碱烧伤所致大鼠角膜新生血管(corneal neovascularization,CNV)的抑制作用。方法采用碱烧伤法制作大鼠CNV模型,75只大鼠随机分为5组:A组为模型对照组,B组为阳性对照组,C组、D组、E组分别为高、中、低剂量CME治疗组,造模后每组均隔日给药,A组给予生理盐水结膜下注射,B组给予0.5g·L-1地塞米松结膜下注射,C组、D组、E组分别给予10.0mg、5.0mg、2.5mg CME结膜下注射。于造模后第4天、第8天、第14天测量CNV的生长面积,并检测角膜组织中血管内皮生长因子(vascular endothelial growthfactor,VEGF)蛋白及其mRNA的表达情况。结果造模后第4天,C组、D组、E组的CNV面积分别为(4.23±1.62)mm2、(6.15±3.52)mm2、(7.78±1.33)mm2,第8天分别为(6.89±1.93)mm2、(10.19±3.37)mm2、(11.51±3.70)mm2,第14天分别为(12.55±3.96)mm2、(17.14±2.71)mm2、(19.77±5.75)mm2,均较A组(12.03±2.09)mm2、(22.09±4.24)mm2、(25.19±2.22)mm2明显减少,差异均有统计学意义(均为P<0.05);C组与B组表达水平相当,差异无统计学意义(P>0.05)。C组、D组、E组角膜组织中VEGF蛋白及其mRNA的表达较A组明显减少,差异均有统计学意义(均为P<0.05);C组与B组表达水平相当,差异无统计学意义(P>0.05)。结论 CME能有效抑制碱烧伤所致大鼠CNV的形成,抑制角膜组织中VEGF的表达可能是其抑制CNV生长的机制之一。

Inhibition of cordyceps militaris extract on corneal neovascularization in rat

Objective To study the inhibition of cordyceps militaris extract(CME) on rat corneal neovascularization(CNV) induced by alkaline burn.Methods CNV model was induced by alkaline burn.Seventy-five rats were randomly divided into group A(model control group),positive control group(group B),high dose of CME group(group C),middle dose of CME group(group D) and low dose of CME group(group E).All groups accepted medication by subconjunctival injection every other day after alkaline burn,saline was injected in group A,0.5 gL-1 dexamethasone in group B,and 10.0 mg,5.0 mg and 2.5 mg CME in group C,D,E,respectively.Area of CNV was measured at 4 days,8 days and 14 days after modeling,and the expression of vascular endothelial growth factor(VEGF) protein and it’s mRNA in corneal tissue was detected.Results Area of CNV in group C,D and E at 4 days were(4.23±1.62)mm2,(6.15±3.52)mm2 and(7.78±1.33)mm2,at 8 days were(6.89±1.93)mm2,(10.19±3.37)mm2 and(11.51±3.70)mm2,at 14 days were(12.55±3.96)mm2,(17.14±2.71)mm2 and(19.77±5.57)mm2,which were all lower than that in group A(12.03±2.09)mm2,(22.09±4.24)mm2 and(25.19±2.22)mm2],there were statistical differences(all P<0.05);These in group B was equal to group C,there was no statistical difference(P>0.05).The expression of VEGF protein and mRNA in corneal tissue in group C,D and E were less than that in group A,there were statistical differences(all P<0.05),which in group C was equal to group B,there was no statistical difference(P>0.05).Conclusion CME can effectively inhibit the CNV induced by alkaline burn in rat,inhibiting the expression of VEGF in corneal tissue may be one of its mechanisms.