The perilymphatic space was perfused with artificial perilymph containing 5×10-3M potassium canrenoate, measuring the EP, K+ and Na+ activity in the scala media with double barrelled K+ or Na+ selective microelectrode. Following the onset of the perfusion, the EP gradually declined and was stable after about 20 minutes. K+ activity also declined gradually but Na+ activity unchanged. When the EP became stable, the artificial ventilation was stopped, the EP dropped to a large negative potential and K+ activity decreased gradually but Na+ activity increased by degrees. The same results were observed in the normal animals when the ventilation was stopped. There are no pathological changes in the TEM view of the stria vascularis. These results suggest that this drug especially affect K+ conductunce of the stria vascularis.
