Abstract
The effect of furosemide on the endocochlear DC potential was studied in kanamycin-poisoned guinea pigs and in control guinea pigs. A rapid and marked decrease in the endocochlear DC potential was found in control animals immediately after the injection of furosemide, and the polarity of the potential turned to negative within 30 seconds after the injection.
The endocochlear DC potential of the kanamycin-poisoned guinea pig showed lesser decrease after the injection of furosemide as compared with the control animal and did not change its polarity to negative. The depressive effect of furosemide on the endocochlear DC potential is thought to be caused by the damage to the stria vascularis. The interaction of kanamycin-poisoning (mainly on the organ of Corti) and furosemidepoisoning (on the stria vascularis) to the endocochlear DC potential was discussed. The fine morphological difference of the cuticular plate on the hair cell which was developed by kanamycin-intoxication might be the site of interaction.
