Crim1在乳鼠肥大心室肌细胞中的表达及AT1R对Crim1表达的调控作用

The expression of Crim1 in hypertrophic ventricular myocytes from neonatal rats and the regulation effect of AT1R on Crim1 expression

目的:探讨富含半胱氨酸型运动神经元蛋白1(Crim1)在肥大心室肌细胞中的表达情况及血管紧张素Ⅱ受体1型(AT1R)对其表达的调控作用。方法:分离获取1日龄SD大鼠乳鼠的原代心室肌细胞,培养48h后换无血清培养基,分为4组:对照组,不予其他干预,培养26h;牵张组,培养2h后牵张刺激24h;氯沙坦组,氯沙坦(终浓度为10μmol/L)干预26h;氯沙坦+牵张组,氯沙坦(终浓度为10μmol/L)预处理2h后牵张刺激24h。检测各组心室肌细胞蛋白/DNA比值、心室肌细胞表面积、Crim1的mRNA和蛋白表达水平。结果:牵张组心室肌细胞蛋白/DNA比值(1.83±0.15对1.16±0.07,P<0.001)、心室肌细胞面积[(591.85±180.20)μm^2对(259.96±54.20)μm^2,P<0.001]均明显高于对照组,氯沙坦+牵张组心室肌细胞蛋白/DNA比值(1.68±0.13对1.83±0.15,P<0.001)、心室肌细胞面积[(372.25±116.13)μm^2对(591.85±180.20)μm^2,P<0.001]均明显低于牵张组。牵张组Crim1的mRNA表达水平(1.14±0.38对4.27±0.11,P<0.001)、蛋白表达水平(19 230.97±2 205.74对37 178.94±1 130.57,P<0.001)均明显低于对照组,氯沙坦+牵张组Crim1的mRNA表达水平(2.24±0.44对1.14±0.38,P<0.05)、蛋白表达水平(28 934.47±1 897.06对19 230.97±2 205.74,P<0.05)均明显高于牵张组。结论:肥大心室肌细胞中Crim1表达下调,AT1R可能参与了对肥大心室肌细胞中Crim1表达的调控。

Objective：To investigate the expression of cysteine-rich motor neuron 1（Crim1）in hypertrophic ventricular neonatal myocytes and the role of angiotensin Ⅱtype 1 receptor（AT1 R）on Crim1 expression. Methods：The primary ventricular myocytes were isolated from 1-day-old SD rats.After 48 hculture,they were replaced with serum-free medium.Cells were divided into four groups depending on the treatment administered.Control group：no intervention culture of 26 h.Stretch group：after cultivating 2 h,stretch for 24 h.Losartan group：losartan（final concentration of 10μmol/L）interferes for 26 h.Losartan＋stretch group：losartan（final concentration of 10μmol/L）pretreatment2 h,followed by a stetch of 24 h.The ventricular myocytes protein/DNA ratio,the surface area of ventricular myocytes,and the expression of Crim1 mRNA and protein were detected. Results：The ventricular myocyte protein/DNA ratio[（1.83±0.15）vs.（1.16±0.07）,P〈0.001]and the surfacearea of ventricular myocytes[（591.85±180.20）μm^2 vs.（259.96±54.20）μm^2,P〈0.001]of stretch group were significantly higher than those of control group,while the ventricular myocyte protein/DNA ratio[（1.68±0.13）vs.（1.83±0.15）,P〈0.001]and the surface area of ventricular myocytes[（372.25±116.13）μm^2 vs.（591.85±180.20）μm^2,P 〈0.001]of losartan＋stretch group weresignificantly lower than those of stretch group.The expression of Crim1 mRNA [（1.14±0.38）vs.（4.27±0.11）,P〈0.001]and protein[（19 230.97±2 205.74）vs.（37 178.94±1 130.57）,P〈0.001]of stretch group were significantly lower than those ofcontrol group,whilethe expression of Crim1 mRNA[（2.24±0.44）vs.（1.14±0.38）,P〈0.05]and protein [（28 934.47±1 897.06）vs.（19 230.97±2 205.74）,P〈0.05]of losartan＋stretch group were significantly higher than those of stretch group.Conclusions：The expression of Crim1 in hypertrophic ventricular myocyte is down-regulated,and AT1 R may be involved in the regulation of the expression of Crim1 in hypertrophic ventricular myocytes.