The afferent signaling complex: regulation of type I spiral ganglion neuron responses in the auditory periphery.

The afferent signaling complex: regulation of type I spiral ganglion neuron responses in the auditory periphery. Hear Res. 2016 Mar 24; Authors: Reijntjes DO, Pyott SJ Abstract The spiral ganglion neurons (SGNs) are the first action potential generating neurons in the auditory pathway. The type I SGNs contact the sensory inner hair cells via their peripheral dendrites and relay auditory information to the brainstem via their central axon fibers. Individual afferent fibers show differences in response properties that are essential for normal hearing. The mechanisms that give rise to the heterogeneity of afferent responses are very poorly understood but are likely already in place at the peripheral dendrites where synapses are formed and action potentials are generated. To identify these molecular mechanisms, this review synthesizes a variety of literature and comprehensively outlines the cellular and molecular components positioned to regulate SGN afferent dendrite excitability, especially following glutamate release. These components include 1) proteins of the SGN postsynapses and neighboring supporting cells that together shape glutamatergic signaling, 2) the ion channels and transporters that determine the intrinsic excitability of the SGN afferent dendrites, and 3) the neurotransmitter receptors that extrinsically modify this excitability via synaptic input from the lateral olivocochlear efferents. This cellular and molecular mach...
Source: Hearing Research - Category: Audiology Authors: Tags: Hear Res Source Type: research