Salicylate-induced morphological changes of isolated inner hair cells and outer hair cells from guinea-pig cochlea

Objectives: The aim of this study is to investigate the salicylate-induced morphological changes of cochlear inner hair cells (IHCs) and outer hair cells (OHCs). Methods: IHCs and OHCs were acutely isolated from the guinea-pig cochlea. Cells were observed under the inverted microscope and 10 mmol/L sodium salicylate solutions or 0.01 mmol/L dexamethasone-plus-salicylate solutions were applied. The cell length or the ratio between the length and width was the indices of the morphological changes in cells. Results: Isolated IHCs did not demonstrate any significant changes in sodium salicylate solutions in 20 min and in 40 min, whereas OHCs were shortened by the 10 mmol/L sodium salicylate to 83% in 20 min and 75% in 40 min. There were no significant differences between in the dexamethasone-plus-salicylate solutions and in the control solutions after 20 min and 40 min both in IHCs and OHCs. Conclusions: Although salicylate affected the isolated OHCs from guinea-pig cochlea, IHCs were not changed morphologically by sodium salicylate applications. Dexamethasone inhibited the salicylate-induced morphological changes of OHCs.