Inhibition of rat PC12 cell calpain activity by glutathione, oxidized glutathione and nitric oxide.
Inhibition of rat PC12 cell calpain activity by glutathione, oxidized glutathione and nitric oxide.
复制标题
谷胱甘肽、氧化型谷胱甘肽和一氧化氮抑制大鼠 PC12 细胞钙蛋白酶活性。
DOI：
10.1016/s0304-3940(01)02161-9
复制
发表时间：
2001
影响因子：
2.5
通讯作者：
DePetrillo,PB
中科院分区：
文献类型：
--
作者：
Rackoff,J;Yang,Q;DePetrillo,PB
Calpain, a calcium activated neutral protease, is involved in mediating neurotoxicity resulting from conditions of oxidative stress and free radical formation, such as hypoxia and ischemia. Nitric oxide (NO) may also be involved in modulating the cytotoxic effects of oxidative stress. We investigated the roles of reduced glutathione (GSH), oxidized glutathione (GSSG), and NO in modulating calpain activity in PC12 cells. Cell extracts were treated with GSSG, GSH, or the NO-donor S-nitroso-N-acetylpenicillamine. Calpain activity was determined by means of a fluorescent assay. Non-linear regression analysis was used to determine the type of inhibition (competitive, uncompetitive, or non-competitive). GSH displayed uncompetitive inhibition, with Ki=7.0±2.0 mM (Mean±SEM) while GSSG exhibited competitive inhibition with Ki=2.5±0.3 mM. NO was an irreversible inhibitor of calpain activity. These results suggest that both GSH and GSSG may be important physiological modulators of calpain activity.
