Endolymphatic sac morphology following long-term kanamycin intoxication.

The well-known toxicity pattern of aminoglycoside antibiotics has been used with the aim to produce waste products in the inner ear. The endolymphatic sac was studied after daily intraperitoneal injection of 75 mg/kg kanamycin for 10 and 20 days to see whether or not the endolymphatic sac showed signs of increased phagocytic activity. The epithelium of the endolymphatic sac was reduced in height, the cells were swollen and extremely thin. The dark epithelial cells were outnumbering the light cells. The subepithelial tissue showed an edematous swelling containing few blood vessels, collagen fibrils and fibroblasts with an empty appearance. There were few wide lateral intercellular spaces and there were intraluminal free floating cells. There were, in all, no clear morphological signs of increased phagocytic activity in the epithelium of the endolymphatic sac.