種々の薬物負荷によるCM,SP,およびAPの変化
スポンサーリンク
概要
- 論文の詳細を見る
Cochlear microphonics (CM), summating potential (SP) and action potential (AP) were measured in animals in which the cochlea was damaged peripherally along the auditory nerve by injection of various kinds of solution into the facial nerve through the stylomastoid foramen as well as damage induced directly by the round window method. Guinea pigs anesthetized with sodium pentobarbital 50mg/kg i. p. were used in all experiments.Results were as follows:I. Cases of injection into the facial nervea) In many cases, CM showed a moderately high amplitude after AP response disappeared.b) In the early stage during the recovery poriod of AP, CM amplitude continued to decrease.c) Only with injection of physiological saline solution was an increase in CM evident to a greater extent than seen in the control or normal CM response.II. Cases of the round window methoda) All applications resulted in a reduction of CM and AP response.b) There was no relationship between the polarity of SP and amplitude of CM. The same amplitude of CM was evident regardless of whether the polarity of SP showed a negative or posititve deflection.c) Only the application of sodium chloride and sodium carbonate induced changes in the polarity in SP from positive to negative voltages.The concentration of sodium and potassium cations in the cochlear lymph may influence changes in the polarity of SP.III. Common results in two proceduresa) In cases of an increased positive SP, either a decreased AP amplitude or no AP responses was obtained.In such cases, there was remarkable degeneration of hair cells as determined histpathologically.b) AP response was always measured during the negative SP. Our findings herein contribute to the knowledge of clinical electrocochleography.
- 耳鼻咽喉科臨床学会の論文