Effects of deafferentation on the electrophysiology of ventral cochlear nucleus neurons.

Published

Journal Article

When cochlear pathology impairs the afferent innervation of the ventral cochlear nucleus (VCN), electrical responses of the auditory brainstem are altered and changes in cell and synaptic morphology are observed. However, the impact of deafferentation on the electrical properties of cells in the VCN is unknown. We examined the electrical properties of single neurons in the anterior and posterior VCN following bilateral cochlear removal in young rats. In control animals, two populations of cells were distinguished: those with a linear subthreshold current-voltage relationship and repetitive firing of action potentials with regular interspike intervals (type I), and those with rectifying subthreshold current-voltage relationships and phasic firing of 1-3 action potentials (type II). Measures of action potential shape further distinguished these two groups. Two weeks following cochlear removal, both electrical response patterns were still seen. Type I cells showed a higher input resistance. Deafferented single-spiking type II cells were slightly more depolarized, had smaller action potentials, smaller afterhyperpolarizations and shorter membrane time constants, whereas multiple-spiking type II cells were apparently unaffected. These changes in the electrical properties of VCN neurons following cochlear injury may adversely affect central processing of sounds presented acoustically or electrically by prostheses.

Full Text

Duke Authors

Cited Authors

  • Francis, HW; Manis, PB

Published Date

  • November 2000

Published In

Volume / Issue

  • 149 / 1-2

Start / End Page

  • 91 - 105

PubMed ID

  • 11033249

Pubmed Central ID

  • 11033249

International Standard Serial Number (ISSN)

  • 0378-5955

Digital Object Identifier (DOI)

  • 10.1016/s0378-5955(00)00165-9

Language

  • eng

Conference Location

  • Netherlands