Induction of calcium efflux from isolated rat-liver mitochondria by 1,2-dibromoethane.
Addition of 1,2-dibromoethane to rat-liver mitochondria induces a concentration-dependent depletion of mitochondrial glutathione. This event seems to be associated with the induction of Ca2+ release from mitochondria pre-loaded with a low pulse of Ca2+. The enhancement of the energy-dissipating process to reaccumulate the released Ca2+ ('Ca2+ cycling') results in a progressive drop of membrane potential. Addition of EGTA (ethyleneglycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid), when the membrane potential has reached the lowest level, restitutes it to a normal value. All these findings and the observation that Ca2+ release also occurs under non cycling conditions (e.g., in the presence of ruthenium red) suggest that 1,2-dibromoethane induces a Ca2+ efflux by activating a selective pathway which is sensitive to critical sulfhydryl groups.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D015946:Ethylene Dibromide / Q000494:pharmacology*; D005978:Glutathione / Q000032:analysis; D006842:Hydrocarbons, Brominated / Q000494:pharmacology*; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D051381:Rats
D006842:Hydrocarbons, Brominated; D015946:Ethylene Dibromide; D005978:Glutathione; D002118:Calcium