Cytochrome c release from brain mitochondria is independent of the mitochondrial permeability transition

FEBS Letters

Andreyev, Alexander Y.¹  Fiskum, Gary¹  Fahy, Brenda¹ 

[1] Department of Anesthesiology, University of Maryland, School of Medicine, MSTF Building, Room 534, 685 W. Baltimore Street, Baltimore, MD 21201, USA

关键词: Cytochrome c;    Permeability transition;    Apoptosis;    Brain mitochondrion;    Calcium;    EGTA;    ethyleneglycol bis-(β-aminoethylether)- N;    N;    N′;    N′-tetraacetic acid;    HEPES;    4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid;    FCCP;    p-trifluoromethoxyphenylhydrazone carbonyl cyanide;    DNP;    2;    4-dinitrophenol;    TPP;    tetraphenylphosphonium;   

DOI  :  10.1016/S0014-5793(98)01394-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Ca²⁺ uptake by brain mitochondria induces the release of up to 40% of total cytochrome c in a cyclosporin A-insensitive manner. In the presence of ATP and Mg²⁺, this process is not accompanied by mitochondrial swelling. There is a moderate decrease in membrane potential under these conditions, but it is completely reversible upon removal of accumulated Ca²⁺ by addition of EGTA+A23187 but not by EGTA alone. These observations provide evidence that cytochrome c release from brain mitochondria does not require the membrane permeability transition. However, brain mitochondria can undergo the permeability transition in the absence of ATP and Mg²⁺, which results in cyclosporin A-sensitive large amplitude swelling, loss of Ca²⁺ uptake capacity and release of matrix solutes.

【 授权许可】

Unknown