Release of cytochrome c from mitochondria to cytosol in gerbil hippocampalCA1 neurons after transient forebrain ischemia

We examined cytosolic cytochrome c in gerbil hippocampal CA1 and CA3 region s after induction of 5-min ischemia by immunoblotting. In the CAI region, c ytochrome c was detected in the cytosolic fraction from 1 to 6 h after isch emia by Western blotting, while it was not detected in the CA3 region. Foll owing intraventricular administration of cyclosporin A (CsA), detectable cy tosolic cytochrome c was dramatically decreased, and about 80% of CAI neuro ns survived after ischemia. The present studies demonstrate that cytochrome c is translocated from mitochondria to the cytosol in the early stage of d elayed neuronal cell death, and suggest the involvement of the mitochondria l permeability transition. (C) 1999 Elsevier Science B.V. All rights reserv ed.