The role of mitochondrial dysfunction in regulation of store-operated calcium channels in glioma C6 and human fibroblast cells

The store-operated calcium influx into electrically non-excitable cells is greatly modified under the condition of deenergized mitochondria in situ. T he rate of calcium influx into cells with empty intracellular calcium store s is greatly diminished when cells were pretreated,vith 2 mu M carbonyl cya nide m-chlorophenylhydrazone (a mitochondrial uncoupler) or with 4 mu M myx othiazol (an inhibitor of the respiratory chain). We demonstrate that this general phenomenon takes place in the case of transformed (glioma C6 and Eh rlich ascites tumor cells) as web as non-transformed (human fibroblasts) ce lls, We also demonstrate that the deenergization of mitochondria affects th e cellular calcium influx rate and not the calcium pump on the plasma membr ane. (C) 2000 Federation of European Biochemical Societies. Published by El sevier Science B.V. All rights reserved.