目的 探讨褪黑素（ melatonin ， MLT ）是否可通过信号调节激酶 / 丝裂原活化蛋白激酶（ ERK/MAPK ）通路调控动脉粥样硬化（ atherosclerosis ， AS ）模型兔动脉内皮细胞肌球蛋白轻链激酶（ myosin light chain kinase ， MLCK ）的表达。 方法 复制兔 AS 模型，分析血清中相关脂质成分的动态变化；γ -32P-ATP 掺入法测定模型兔主动脉的 MLCK 活性；动脉经冰冻切片，免疫组化检测动脉内膜 MLCK 的表达，伊红（ HE ）染色观察动脉壁的形态结构； Western blot 检测 AS 兔动脉组织 MLCK 的表达和 ERK 磷酸化水平。 结果 AS 兔模型复制成功，实验兔在高胆固醇（ cholesterol ， Cho ）饮食 4 ， 8 ， 12 周后，与正常对照相比，血清中相关生化指标有逐渐增加趋势（ <> P <0.05 ）；γ -32P-ATP 掺入法显示动脉组织中 MLCK 的活性呈逐渐增强趋势（ <> P <0.05 ）， Western blot 和免疫组化则显示动脉内皮细胞 MLCK 的表达、 ERK 磷酸化水平亦呈逐渐增强趋势， HE 染色显示主动脉内膜逐渐增厚，细胞间隙逐渐增大；而加喂 MLT 后，动脉组织 MLCK 的表达、 ERK 磷酸化水平及 MLCK 的活性和主动脉内膜通透性均有所下降，而泡沫细胞形成量逐渐增多，至高 Cho 饮食 12 周时则形成了明显的 AS 斑块，加喂 MLT 后，主动脉内膜病变则有一定程度减轻。 结论 MLT 可能通过 ERK/MAPK 通路下调模型兔动脉内皮细胞 MLCK 活性而减轻 AS 斑块的病变程度。
Abstract
OBJECTIVE To study the expression of myosin light chain kinase(MLCK) in endothelial cell regulated by the melatonin through the pathway of ERK/MAPK in atherosclerosis(AS) model rabbit. METHODS The model rabbit of AS was established and the dynamic variability of the lipids in the serum of model rabbits was analyzed. The MLCK activity of artery tissue of model rabbits was measured by the method of γ-32P-ATP incorporated.The expression of MLCK in the endothelial cell was detected by immunohistochemistry and western blot, meanwhile, the phosphorylation of ERK in the endothelial cell was also detected by western blot. The change of morphology of artery wall in model rabbits was examined according to the HE stain. RESULTS The AS rabbit model was established successfully. After being fed with the high cholesterol (Cho) for 4,8,12 weeks, compared with the normal control, the related biochemistry quotas was increased obviously in the serum (P<0.05),the MLCK activity of artery tissue of model rabbits was increased gradually(P<0.05),the expression of MLCK and the phosphorylation of ERK in the artery tissue were raised gradually. At the same time，the HE staining indicated the increase of foam cells products. When melatonin（MLT） was added into the high Cho food,the activity of MLCK,the permeability of arterial wall,the expression of MLCK and the phosphorylation of ERK in artery tissue were decreased. The aortic tunica intima symptom seem to be reliefed. CONCLUSION MLT may relief the pathological changes of plaque in the AS model rabbit through the pathway of ERK/MAPK to down regulate the activity of MLCK in endothelial cell.
关键词
褪黑素 /
动脉粥样硬化 /
动脉 /
肌球蛋白轻链激酶
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Key words
melatonin /
atherosclerosis /
artery /
myosin light chain kinase
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参考文献
[1] ANTOHE F. Endothelial cells and macrophages, partners in atherosclerotic plaque progression[J]. <>Arch Physiol Biochem, 2006,112(4):245-253.
[2] LIBBY P, AIKAWA M, JAIN M K. Vascular endothelium and atherosclerosis[J] .<>Handb Exp Pharmacol,2006, (176 Pt 2):285-306.
[3] LIOU S F, YEH J L, LIANG J C, <>et al. Inhibition of mitogen-mediated proliferation of rat vascular smooth muscle cells by labedipinedilol-A through PKC and ERK 1/2 pathway[J] .<>J Cardiovasc Pharmacol, 2004,44(5):539-551.
[4] GIROTTI L, LAGO M, IANOVSKY O, <>et al. Low urinary 6-sulphatoxymelatonin levels in patients with coronary artery disease[J]. <>J Pineal Res, 2000,29(3):138-142.
[5] SAKOTNIK A, LIEBMANN P M, STOSCHITZKY K, <>et al. Decreased melatonin synthesis in patients with coronary artery disease[J] .<>Eur Heart J,1999,20(18):1314-1317.
[6] SEWWRYNEK E. Melatonin and the cardiovascular system[J]. <>Neuro Endocrinol Lett,2002,23(Suppl1):79-83.
[7] ZHU H Q, CHENG X W, XIAO L L <>et al. Melatonin prevents oxidized low-density lipoprotein-induced increase of myosin light chain kinase activation and expression in HUVEC through ERK/MAPK signal transduction[J].<>J Pineal Res,2008, 45 （ 3 ）： 328-334.
[8] DAI M, LI H K. Effect of paeonol on proliferation of vascular smooth muscle cell in atherosclerosis rabbits[J]. <>Chin Pharmacol Bull （中国药理学通报） ,2006, 22(5): 587-591.
[9] CHEN Y, LEE M Y, CHEN H Y, <>et al. Melatonin attenuates the postischemic increase in blood-brain barrier permeability and decreases hemorrhagic transformation of tissue-plasminogen activator therapy following ischemic stroke in mice[J]. <>J Pineal Res, 2006,40(3):242-250.
[10] TANG Y L, HU C P, FENG J T, <>et al. Regulation effect of nerve growth factor on Ras-MAPK signal transduction pathway in neurogenic inflammation of asthma[J] <>J Cent South Univ(<>Med Sci) （中南大学学报 医学版） , 2006,31(3):319-325.
[11] SUN B, LI L S,WEN G L, <>et al. Melatonin ， free radicals and cardiovascular diseases[J]. <>Adv Cardiovas Dis （心血管病学进展） , 2002, 23(3):142-144.
（ 收稿日期 ： 2008-09-10 ）
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