Reversible S-nitrosation of creatine kinase by nitric oxide in adult rat ventricular myocytes
Reversible S-nitrosation of creatine kinase by nitric oxide in adult rat ventricular myocytes
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DOI：
10.1006/jmcc.1998.0662
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发表时间：
1998-05-01
影响因子：
5
通讯作者：
Kelly, RA
中科院分区：
文献类型：
--
作者：
Arstall, MA;Bailey, C;Kelly, RA
我们先前已经证明，一氧化氮(NO)供体S-亚硝基-N-乙酰半胱氨酸(SNAc)可逆地降低大鼠心脏标本中肌酸激酶(CK)的活性，显著抑制心肌对变力刺激的收缩反应。为了进一步研究外源性和内源性NO对成年大鼠心肌细胞GK的S亚硝化及随后的酶活性的影响，兔骨骼肌CK在溶液中亚硝化后，在GK二聚体中形成两个S亚硫基。对于NO供体S-亚硝基-N-乙酰青霉胺(SNAP)和SNAG，在溶液和ARVM裂解液中，由S亚硝化引起的CK失活均呈时间和浓度依赖性，并可被巯基二硫苏糖醇(DTT)迅速逆转。同样，SNAG或SNAP可剂量依赖性地降低完整ARVM的CK活性，通过电起搏增加细胞的代谢活性可进一步减弱这一作用。ARVM与白细胞介素1β(IL-1β)和干扰素-γ(干扰素-γ)处理的心肌微血管内皮细胞(CMEC)共培养时，心肌细胞CK活性未见明显下降。升高GSH水平可减轻SNAG引起的心肌细胞CK活性下降，而降低心肌细胞GSH水平则增强了SNAG对完整心肌细胞CK活性的抑制作用。这些数据表明，NO对心肌细胞CK的抑制程度与心肌细胞代谢活动的程度和细胞内GSH含量有关。(C)1998年学术出版社有限公司。
We have previously demonstrated that the nitric oxide (NO) donor S-nitroso-N-acetylcysteine (SNAC) reversibly decreases the activity of creatine kinase (CK) in an isolated rat heart preparation, markedly suppressing myocardial contractile responsiveness to an inotropic challenge. We wished to further examine the role of exogenous and endogenous sources of NO species on S-nitrosation of GK and subsequent enzyme activity in adult rat ventricular myocytes (ARVM), Two S-nitrosothiol groups were formed in the GK dimer after nitrosation of rabbit skeletal muscle CK in solution. CK inactivation due to S-nitrosation was time-and concentration-dependent in solution and in ARVM lysate for both NO donors S-nitroso-N-acetylpenicillamine (SNAP) and SNAG and was rapidly reversible with the sulfhydryl dithiothreitol (DTT). Similarly, SNAG or SNAP dose-dependently decreased CK activity in intact ARVM, which was further attenuated by increasing the metabolic activity of the cells with electrical pacing for 1 h. Co-cultures of ARVM with interleukin 1 beta (IL-1 beta)- and interferon gamma (IFN gamma) pretreated cardiac microvascular endothelial cells (CMEC) caused no detectable decline in myocyte CK activity. Increasing GSH levels attenuated the decline in myocyte CK activity with SNAG, while decreases in myocyte GSH levels enhanced the inhibitory effect of SNAG on intact myocyte CK activity. These data indicate that the degree of inhibition of cardiac myocyte CK by NO is dependent on the extent of myocyte metabolic activity and the intracellular GSH content. (C) 1998 Academic Press Limited.