Damage to the stria vascularis in the guinea pig by acute atoxyl intoxication.

The aim of the present study was to show the morphological degeneration at the ultrastructural level, after damaging the stria vascularis experimentally. The acute lesions, after acute atoxyl intoxication, occur after about 12 hours, and begin as a degeneration of both the marginal and the intermediate cells, whereas the basal cells remain mainly unaffected. The severely damaged marginal or intermediate cells may become loosened from the stria vascularis and rejected from it into the endolymphatic space. Under such conditions the basal cells may line the surface facing the endolymph, although this occurs very rarely. Intially, there may be a slight bulging of Reissner's membrane, but soon the membrane becomes depressed, and sometimes a total collapse occurs, with Reissner's membrane flattened over the tectorial membrane against the organ of Corti. It is only seldom that Reissner's membrane touches the strial surface. Mitochondrial degeneration with formation of intramitochondrial inclusion bodies is an interesting early finding in the damage pattern.