Blebs in inner and outer hair cells: a pathophysiological hypothesis

Abstract

Introduction: The ototoxic effects of cisplatin include loss of outer hair cells, degeneration of the stria vascularis and a decrease in the number of spiral ganglion cells. Scanning microscopy has shown balloon-like protrusions (blebs) of the plasma membrane of inner hair cells following cisplatin administration. The present study was undertaken to identify the possible role of inner and outer hair cell blebs in the pathogenesis of cisplatin-induced ototoxicity.

Materials and methods: Twenty-five guinea pigs were injected with cisplatin and their hearing tested at different time-points, before sacrifice and examination with scanning electron microscopy.

Results and analysis: Seven animals showed blebs in the inner hair cells at different stages. Hearing thresholds were lower in animals showing blebs.

Discussion: Cisplatin seems to be able to induce changes in inner hair cells as well as in other structures in the organ of Corti. Blebbing observed in animals following cisplatin administration could play a specific role in the regulation of intracellular pressure.