Abstract
This time, by staining the potassium in affected and normal inner ears of guinea-pigs for visual comparison, the function of this substance was investigated in physiological aspects.
1) The noise-exposure group:
Potassium in cochlea was densely stained and localized in hair cells for some while after 2 hours' exposure to white noise of 105-110 phons, but after 5-7 hours of exposure the density was found reduced or limited. Stimulation of longer duration effected decrease or limitation of that substance in cells of Corti's organ, stria vascularis and spiral ganglion cells especially at those parts which seem to be particularly related with stimulation, such as Corti's organ. In Corti's organ, spiral ganglion cells and stria vascularis, the fluctuation of potassium effected by the experimental conditions tended to be of more significance in basal turn. A long exposure did not seem to reduce in acoustic nerve fiber very much.
2) The streptomycin injection group:
At 30-60 minutes after 400-500mg/kg injection of streptomycin, potassium value was found generally less fluctuated than 1in the cases of noise exposure. While in the injected group, the distribution being just as normal in cells and tissues and there was slight oedema in the cells. A little increases were noticed after the twice injection. In most cases, however, after 3-4 days (one injection a day), the density of stained potassium showed a diminishing tendency and that fluctuation of potassium tended to be of more significance in basal turn. Little change took place in acoustic nerve fiber. From this fact, enzymes in stria vascularis seem to have relation for transport of the electrolytes.
