Sun Ying-Gang, Wang Xin-Yan, Chen Xiu, Shen Cheng-Xing, Li Yi-Gang
Department of Cardiovascular Diseases, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200092, China.
Department of Anatomy and Physiology, Shanghai Institute of Health Science Shanghai 201318, China.
Int J Clin Exp Pathol. 2015 Jan 1;8(1):474-81. eCollection 2015.
Hydrogen sulfide (H2S), produced by cystanthionine-γ-lysase (CSE) in the cardiovascular system, is an endogenous gaseous mediator exerting pronounced physiological effects as the third gasotransmitter in addition to nitric oxide (NO) and carbon monoxide (CO). Accumulating evidence indicated that H2S could mediate the cardioprotective effects in myocardial ischemia model. Ventricular arrhythmia is the most important risk factor for cardiac mortality and sudden death after acute myocardial infarction (AMI). The potential impact of H2S on cardiomyocytes electrical remodeling post ischemic insult is not fully explored now. Present study investigated the role of H2S on cardiomyocytes electrical remodeling in rats with ischemia/reperfusion injury. H2S concentration was reduced and arrhythmia score was increased in this model. CSE mRNA level was also upregulated in the ischemic myocardium. Exposure to exogenous NaHS reduced the action potential duration (APD), inhibited L-type Ca(2+) channels and activated K(ATP) channels in cardiomyocytes isolated from ischemic myocardium Exogenous H2S application improves electrical remodeling in cardiomyocytes isolated from ischemic myocardium. These results indicated that reduced H2S level might be linked to ischemia/reperfusion induced arrhythmias.
心血管系统中的胱硫醚-γ-裂解酶(CSE)产生的硫化氢(H₂S)是一种内源性气体介质,作为除一氧化氮(NO)和一氧化碳(CO)之外的第三种气体递质发挥着显著的生理作用。越来越多的证据表明,H₂S可介导心肌缺血模型中的心脏保护作用。室性心律失常是急性心肌梗死(AMI)后心脏死亡和猝死的最重要危险因素。目前尚未充分探讨H₂S对缺血性损伤后心肌细胞电重构的潜在影响。本研究调查了H₂S在缺血/再灌注损伤大鼠心肌细胞电重构中的作用。该模型中H₂S浓度降低,心律失常评分增加。缺血心肌中的CSE mRNA水平也上调。暴露于外源性硫氢化钠(NaHS)可缩短缺血心肌分离的心肌细胞的动作电位时程(APD),抑制L型钙通道并激活ATP敏感性钾通道(KATP)。外源性H₂S可改善缺血心肌分离的心肌细胞的电重构。这些结果表明,H₂S水平降低可能与缺血/再灌注诱导的心律失常有关。