Bellomo G, Jewell S A, Thor H, Orrenius S
Proc Natl Acad Sci U S A. 1982 Nov;79(22):6842-6. doi: 10.1073/pnas.79.22.6842.
In suspensions of isolated hepatocytes, two intracellular Ca2+ pools were distinguished in the presence of the metallochrome indicator arsenazo III, first by treatment with the uncoupler carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) and then with the Ca2+ ionophore A23187. The available evidence indicates that the two pools are of mitochondrial and extramitochondrial origin. Metabolism of t-butyl hydroperoxide by hepatocytes caused release of Ca2+ from both compartments concomitant with oxidation of cellular glutathione and NADPH, which was followed by characteristic alterations in cell surface structure. When NADPH oxidation was prevented by selective inactivation of glutathione reductase, t-butyl hydroperoxide metabolism was without effect on the mitochondrial Ca2+ pool, whereas the loss from the extramitochondrial pool was accelerated. Our results suggest that different regulatory mechanisms modulate mitochondrial (NADPH-dependent) and extramitochondrial (thiol-dependent) Ca2+ compartmentation and that disturbance of normal Ca2+ homeostasis may be critical in peroxide-induced cytotoxicity.
在分离的肝细胞悬液中，在金属铬指示剂偶氮胂III存在的情况下，区分出两个细胞内钙池，首先用解偶联剂羰基氰对三氟甲氧基苯腙（FCCP）处理，然后用钙离子载体A23187处理。现有证据表明，这两个钙池分别起源于线粒体和线粒体外。肝细胞对叔丁基过氧化氢的代谢导致两个区室的钙离子释放，同时伴随着细胞内谷胱甘肽和NADPH的氧化，随后细胞表面结构发生特征性改变。当通过谷胱甘肽还原酶的选择性失活来阻止NADPH氧化时，叔丁基过氧化氢代谢对线粒体钙池没有影响，而线粒体外钙池的钙离子丢失加速。我们的结果表明，不同的调节机制调节线粒体（依赖NADPH）和线粒体外（依赖硫醇）的钙离子分隔，并且正常钙离子稳态的紊乱可能在过氧化物诱导的细胞毒性中起关键作用。
