Enkephalin Suppresses Afferent Cochlear Neurotransmission

Publisher Website
Google Scholar
Abstract
The effects of enkephalin and naloxone, applied iontophoretically, were tested on induced firing activity of the afferent dendrites on inner hair cells in the guinea pig. Enkephalin strongly depresses the depolarizing effect of N-methyl-D-aspartate (NMDA), quisqualate and kainate. Enkephalin exerted a stronger inhibitory effect on non-NMDA-induced fibre activity than on NMDA-induced activity. It was possible to block this inhibitory effect by applying the opiate antagonist naloxone, which suggests a specific enkephalin action. Our results appear to demonstrate that enkephalin acts as a neurotransmitter or a neuromodulator in the efferent neurones of inner hair cells which have synaptic contact to the afferents of the inner hair cells.

This publication has 0 references indexed in Scilit: