Open AccessPermeability transition‐independent release of mitochondrial cytochrome c induced by valinomycin
Author(s) -
Shinohara Yasuo,
Almofti Mohamad Radwan,
Yamamoto Takenori,
Ishida Taro,
Kita Fumiyo,
Kanzaki Hideki,
Ohnishi Masakatsu,
Yamashita Kikuji,
Shimizu Shigeomi,
Terada Hiroshi
Publication year - 2002
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1033.2002.03229.x
Subject(s) - valinomycin , mitochondrial permeability transition pore , mitochondrion , cytochrome c , biophysics , chemistry , permeability (electromagnetism) , membrane potential , inner mitochondrial membrane , membrane , biochemistry , biology , apoptosis , programmed cell death
To examine whether valinomycin induces a mitochondrial permeability transition (PT), we investigated its effects on mitochondrial functions under various conditions. The acceleration of mitochondrial respiration and swelling, induced by valinomycin, were found to be insensitive to inhibitors of the ordinary PT, indicating that valinomycin does not induce the ordinary PT. Results of experiments using mitochondria isolated from transgenic mice expressing human bcl‐2 also supported this conclusion. Furthermore, evidence for induction of PT pores by valinomycin was not obtained by either electron microscopic analysis of mitochondrial configurations or by measurement of the permeability of the inner mitochondrial membrane by use of polyethylene glycol. However, valinomycin did induce a significant release of cytochrome c , and thus it may be a nice tool to study the processes of mitochondrial cytochrome c release.