Ultrastructure of the stria vascularis, vestibular dark cells and endolymphatic sac following acute diuretic ototoxicity

The aim of this study was to test this possibility by studying ultrastructural changes that followed acute ethacrynic acid, furosemide, and piretanide (PIR) ototoxicity in guinea pigs. In summary, vesiculation, vacuolization, and intercellular edema of the marginal cells and shrinkage of the intermediate cells are the most prominent ultrastructural findings among the diuretic-treated groups. The authors postulate that the intracellular vesiculation, vacuolization, and subsequent exocytosis at the basolateral side of the marginal cells is the mechanism by which the swollen cell attempts to regulate its volume. The ultrastructural changes in the vestibular dark cells and endolymphatic sac epithelial cells are subtle, if present at all, and the moderate increase in vesiculation and vacuolization in some of the dark cells and sac epithelial cells appears to be related to diuretic ototoxicity.