抄録
The effect of furosemide upon the endocochlear DC potential (EP) was studied. The injection of furosemide in 10mg/kg body weight caused an increase of EP and then a gradual decrease. With the injection of 20mg/kg body weight of furosemide the EP decreased, recovered within 1 hour and then decreased.
Following the initial injection of 20mg/kg of furosemide the second injection of 20mg/kg of furosemide was administered at two hours. EP decreased, recovered incompletely and then decreased to less than 5mV. Two of seven cases caused a depression of EP and a gradual recovery close to 0 mv within 1 hour following the second injection of 20mg/kg of furosemide. The initial depression of EP caused by 20mg/kg of furosemide would depend upon the suppression of active sodium transport in the stria vascularis.
The second depression of EP caused by 20mg/kg of furosemide would be due to the histological changes in the stria vascularis. The variation of EP caused by furosemide was similar to that of CM. Therefore the hearing loss caused by furosemide appeared to be dependent upon the changes of the endolymphatic ion composition by suppression of active sodium transport in the stria vascularis and by damage in the stria vascularis.
