摘要
目的探讨κ阿片受体(κ-OR)激动抑制异丙肾上腺素(Iso)诱导的乳鼠心肌细胞肥大的信号转导机制。方法利用体外培养模型,以Iso 10μmol/L诱导心肌细胞肥大,观察κ-OR激动剂U50488 H1μmol/L的作用,并进一步探索在钙调神经磷酸酶(CaN)特异性抑制剂环孢菌素A(CsA)、细胞外信号调节激酶(ERK)抑制剂U0126、L型钙通道阻滞剂维拉帕米及β肾上腺素受体阻断剂普萘洛尔存在的情况下,κ-OR的激活对心肌肥大的影响。Lowry法测心肌细胞蛋白含量;消化分离法及计算机图像分析系统测细胞体积;采用Till阳离子测定系统,以Fura-2/AM为荧光探针,观察胞内[Ca2+]i瞬间变化;Western blot法测CaN、ERK表达。结果U50488 H1μmol/L可以明显抑制Iso诱导的心肌蛋白含量增加、体积增大和胞内[Ca2+]i瞬间变化的增高,其抑制程度与CsA、U0126、维拉帕米及普萘洛尔相似;U50488 H可以抑制Iso诱导的CaN表达增加和ERK磷酸化增加;CaN抑制剂CsA可以抑制Iso诱导的ERK磷酸化增加,ERK抑制剂U0126可以抑制Iso诱导的CaN表达增加。结论κ-OR激动通过CaN、ERK信号抑制Iso诱导的心肌肥大,在这一过程中,CaN、ERK信号在蛋白水平上存在交互作用。
Objective To observe the inhibitory effects and signal transduction of kappa-opioid receptor（κ-OR）stimulation on hypertrophy of cardiomyocytes induced by isoproterenol in neonatal rats.Methods The total protein content was measured by the method of Lowry.The cardiomyocytes volume was measured by computer photograph analysis system.i transient was measured by Till image system using Fura-2/AM as fluresence indicator.The expression of calcineurin（CaN） and phosphorylation of extracellular signal-regulated kinase（ERK） were determinded by Western bolt.Results U50488H（1 μmol/L） attenuated the increase of total protein content,cardiomyocytes volume induced by isoproterenol,to the extent similar to that of Cyclosporine A（CsA,the inhibitor of CaN）,U0126（the inhibitor of ERK）,verapamil and propranolol.U50488H also attenuated the expressions of CaN and ERK phosphorylation induced by isoproterenol.The phosphorylation of ERK induced by isoproterenol was decreased by CsA,while the expression of CaN induced by isoproterenol was attenuated by U0126.Conclusion Activation of κ-opioid receptor may abolish the hypertrophic effect in response to isoproterenol stimulation through the CaN,ERK signalling pathway.
出处
《中华高血压杂志》
CAS
CSCD
北大核心
2010年第3期273-278,共6页
Chinese Journal of Hypertension
基金
辽宁省自然科学基金资助(20082181)
辽宁省教育厅团队项目(2007T113)
辽宁省高等学校优秀人才支持计划(2008RC33)
关键词
Κ阿片受体
钙调神经磷酸酶
胞外信号调节激酶
心肌肥大
Kappa-opioid receptor
Calcineurin
Extracellular signal-regulated kinase
Myocardial hypertrophy
