Cytochrome c redistribution in apoptosis of guinea pig vestibular hair cells.

We examined the cellular location of cytochrome c in healthy and in streptomycin-damaged vestibular hair cells by immunohistochemistry. Staining for cytochrome c revealed an immunostain pattern that was consistent with a mitochondrial distribution of this enzyme in healthy hair cells, while in hair cells affected by aminoglycosides, a diffuse distribution in the cytoplasm was found together with apoptotic nuclear morphology. These findings suggest that redistribution of cytochrome c is involved in the pathway of apoptosis in vestibular hair cells induced by aminoglycosides.