Cyclosporin A-sensitive release of Ca2+ from mitochondria in intact thymocytes.
Release of Ca2+ from mitochondria into cytosol in intact thymocytes was studied using the fluorescent dye Fluo-3. It was shown that the release of Ca2+ induced by the dithiol cross-linking agent phenylarsine oxide or by uncoupler was strongly inhibited by cyclosporin A, a specific inhibitor of the permeability transition pore (PTP) in mitochondria. Oxidative stress sensitized the pore so even partial uncoupling caused rapid cyclosporin A-sensitive release of Ca2+. The experiments on digitonin-permeabilized cells confirmed that uncoupling induced opening of the PTP, which forms the major pathway for rapid release of Ca2+ from thymocyte mitochondria.
Chernyak
B V
BV
A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russia. bchern@energ.genebee.msu.su
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D002478:Cells, Cultured; D016572:Cyclosporine / Q000494:pharmacology*; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism; D007700:Kinetics; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D018384:Oxidative Stress; D010539:Permeability; D051381:Rats; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D013950:Thymus Gland
D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D016572:Cyclosporine; D002118:Calcium