维生素E对动脉粥样硬化兔动脉肌球蛋白轻链激酶活性及内膜通透性的影响

Effect of vitamin E on myosin light chain kinase activity and endothelial permeability of the artery in atherosclerotic rabbit

目的 :探讨维生素 E(Vit E)对动脉粥样硬化兔动脉肌球蛋白轻链激酶 (ML CK)活性及内膜通透性变化的影响。方法 :复制兔动脉粥样硬化模型 ,用γ 32 P掺入法检测动脉 ML CK活性 ,免疫荧光检测内膜通透性 ,同时用苏木精伊红 (HE)染色观察动脉壁的形态结构。结果 :在喂饲胆固醇膳食 4周的动物组 ,动脉 ML CK活性与正常对照组比较显著升高 (P<0 .0 5 ) ;但在喂饲胆固醇膳食 12周或同时添加 Vit E后 ,动脉 ML CK活性与正常对照组比较升高不明显 (P>0 .0 5 )。荧光显微镜下观察显示 ,兔动脉内膜通透性在喂饲胆固醇膳食后 4周有所增加 ,12周后显著增加 ;12周组膳食中同时加 Vit E后 ,通透性有所下降。结论 :在动脉粥样硬化早期 ,内膜屏障完整性的改变可能与 ML CK活性增强有关 ,Vit E可能是降低动脉内膜 ML CK活性的因素 ,并能降低动脉粥样硬化模型兔动脉内膜通透性。

Objective: To study the effect of vitamin E(Vit E) on the myosin light chain kinase(MLCK) activity and the endothelial permeability of the artery in atherosclerotic rabbits. Methods: The MLCK activity of rabbit artery was measured by incorporation of γ 32 P. The endothelial permeability was accessed by immunofluorescence . Results: The model of atherosclerosis was established after rabbits were fed with cholesterol for four weeks. The activity of MLCK increased markedly, and there was significantly statistical difference compared with the normal control ( P <0 05). When the rabbits were fed with cholesterol for twelve weeks or with cholesterol and Vit E for twelve weeks, the activity of MLCK did not change markedly, and there was no statistical difference compared with the normal control, respectively ( P >0 05). The permeability of arterial wall was increased after the rabbits were fed with cholesterol for four weeks, and the permeability increased even more obviously after the rabbits were fed with cholesterol for twelve weeks. The permeability appeared to be decreased when Vit E was added into the cholesterol feeding. Conclusion: The change in integrity of arterial wall may be associated with the increase of the activity of MLCK. Vit E may decrease the MLCK activity. Vit E may decrease the endothelial permeability of atherosclerotic rabbits.