褪黑素对动脉粥样硬化模型兔动脉肌球蛋白轻链激酶表达及活性的影响

Effect of melatonin on expression and activity of myosin light chain kinase in the artery wall of atherosclerotic rabbits

目的探讨褪黑素(melatonin,MLT)对动脉粥样硬化模型兔动脉肌球蛋白轻链激酶(MLCK)表达与活性的影响。方法复制动脉粥样硬化兔模型,采用免疫组化和Western blot分析主动脉MLCK蛋白表达,γ-32P-ATP参入法检测MLCK活性。结果成功建立动脉粥样硬化兔模型,高脂喂食12wk,兔主动脉MLCK蛋白表达水平增加,活性上升,经MLT治疗后动脉粥样硬化斑块减少,MLCK蛋白表达下降,活性下降。结论动脉粥样硬化的形成与MLCK蛋白表达与活性升高有关,MLT能降低动脉MLCK蛋白表达和活性。

Aim To study the effect of melatonin on expression and activity of myosin light chain kinase in the artery wall of atherosclerotic rabbits. Methods The rabbit model of atherosclerosis was induced by a high-cholesterol diet. The blood lipid levels were assayed in the serum of each group. MLCK expression was detected by Western blot and immunohistochemical method. MLCK activity was measured by γ-32p-ATP incorporation into myosin light chain. Results The ath- erosclerosis model was established successfully. The levels of lipids decreased after MLT treatment. After fed with cholesterol ＇for twelve weeks, the expression and activity of MLCK in the artery of atherosclerotic rabbits increased markedly, whereas there was no obvi- ous difference in expression of MLCK in the artery of atherosclerotic rabbits fed with cholesterol and melato- nin for twelve weeks compared with that of control. Conclusions It was suggest that high expression and activity of MLCK in the artery might be closely correla- ted with the development of atherosclerosis. Melatonin played an important role in inhibiting the development of atherosclerosis by decreasing the expression and ac- tivity of MLCK.