Naseem K M, Bruckdorfer K R
Department of Biochemistry and Molecular Biology, Royal Free Hospital School of Medicine, London, U.K.
Biochem J. 1995 Aug 15;310 ( Pt 1)(Pt 1):149-53. doi: 10.1042/bj3100149.
Simultaneous application of NO and H2O2 to human platelets at physiologically relevant concentrations increased inhibition of platelet aggregation by NO almost 100-fold. If NO and H2O2 were mixed before the addition to platelets, the inhibitory effect remained but still depended on the presence of NO. This suggested an enhanced sensitivity of the platelets to residual NO in the presence of H2O2. The inhibition by the NO/H2O2 mixture was not due to peroxynitrite and was only partly reversed by radical scavengers. The mechanism includes enhanced formation of cyclic GMP in response to NO in the presence of H2O2. H2O2 may play a positive physiological role by amplification and/or prolongation of the action of NO.
在生理相关浓度下,将一氧化氮(NO)和过氧化氢(H₂O₂)同时应用于人体血小板,可使NO对血小板聚集的抑制作用增强近100倍。如果在添加到血小板之前将NO和H₂O₂混合,抑制作用仍然存在,但仍依赖于NO的存在。这表明在H₂O₂存在的情况下,血小板对残余NO的敏感性增强。NO/H₂O₂混合物的抑制作用不是由于过氧亚硝酸盐,并且仅部分被自由基清除剂逆转。其机制包括在H₂O₂存在下,对NO的反应中环状鸟苷酸(cGMP)形成增加。H₂O₂可能通过放大和/或延长NO的作用发挥积极的生理作用。