RESUMO
OBJECTIVE: To investigate the effects of sodium salicylate and extracellular K(+) on the functions of outer hair cells (OHCs) and the relations between their actions. METHODS: Sodium salicylate at the concentration of 1 mmol/L was administered either alone or following 10 mmol/L KCl into the extracellular solution of OHCs isolated from guinea pig cochlea. The outward potassium current (IK) and resting potential (RP) of OHCs was measured using patch-clamp whole cell recording technique. RESULTS: Time-dependent changes in the effect of sodium salicylate on IK was observed, namely, IK underwent transient increase and then declined after sodium salicylate administration. When KCl was administered previously into the extracellular solution, the effect of sodium salicylate on IK was reduced. Sodium salicylate could decrease RP but not time-dependently in the absence of KCl, and when prior KCl treatment was administered, only temporary increase in RP took place before RP returned to the level before sodium salicylate administration.?? CONCLUSIONS: The effects of sodium salicylate on OHC functions were related to K(+), and the former agent may affect K(+) conduction and internal and external distribution of K(+) in OHCs, and causes the changes in the excitability and mechanical activity of OHCs by means of affecting IK and RP. This hypothesis might be one of the cochlear mechanisms by which sodium salicylate affects OHC functions.