血管灌流法による蝸牛糖代謝の電気生理学的研究

抄録

We studied on the effect of vascular perfusion of anterior inferior cerebellar artery with synthetic blood containing no metabolic substrate upon cochlear potentials of guinea pig.
During perfusion of glucose-free blood, the endolymphatic potential (EP) and the cochlear microphonics (CM) were maintained for 86±20(S.D.) minutes. Subsequently, the EP and the CM declined slowly and reached a temporal steady-state level of 30mV about 60 minutes after the onset of decline.
Strial glycogen seemed to play no role in this prolonged maintenance of the potentials, because significant breakdown of strial glycogen did not occure until the potentials started to decline. It appeared that the prolonged initial maintenance of the potentials during perfusion of glucose-free blood was due to the utilization of glucose from perilymph, since the EP started to decline immediately when the perilymphatic glucose pool was removed simultaneously by perilymphatic perfusion.
In addition, the minimal concentration at which glucose, lactate, succinate and pyruvate could sustain the potentials were determined. Consequently we found that the EP and the CM were supported by 0.8mM glucose, 11mM lactate and 11mM pyruvate but not by succinate.