Effcts on the Inner Ear Fluids of Saturated NaCl Solution Applied to the Round Window Membrane

Abstract

After the application of saturated NaCl solution to the round window membrane, the K⁺ or Na⁺ activity was recorded in perilymph or endolymph of the basal turn with the double barrelled K⁺ or Na⁺ selective microelectrode for 60 minutes. The K⁺ and Na⁺ activities in the scala tympani rapidly increased and then decreased. The K⁺ activity in the scala media also rapidly insreased and then decrased, but the Na⁺ activity continued to increase during 60 minutes. After the application the K⁺ activity in the scala vestibuli did not change, the Na⁺ activity slightly increased. These results suggest that the K⁺ and Na⁺ clearances are higher in the scala vestibuli than in scala tympani, and Na⁺ clearance is lower than K⁺ clearance in the scala media.