Deafness-induced plasticity in the mature central auditory system.
Studies in rats and guinea pigs indicate that local changes in inhibitory transmitters may underlie deafness-induced plastic changes in electrophysiological responsiveness of cells of the mature central auditory system. Following 21 days of bilateral deafness there is an increase in evoked Fos-immunoreactive neurones in the central nucleus of the inferior colliculus (CIC) to contralateral cochlear electrical stimulation, compared with normal or 1-day deafened animals. Deafness is also associated with a dramatic reduction in the population of CIC neurones that respond with suppression of activity to electrical stimulation. Moreover, in vivo microdialysis reveals a marked decrease in gamma-aminobutyric acid (GABA) release from the CIC cells in deafened animals. The results may have general implications for the mediation of central nervous system plasticity induced by deafferentation of sensory input.
Bledsoe
S C
SC
Department of Otolaryngology, University of Michigan, Ann Arbor 48109-0506, USA.
Nagase
S
S
Miller
J M
JM
Altschuler
R A
RA
D000818:Animals; D003638:Deafness / Q000503:physiopathology*; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000502:physiology; D006168:Guinea Pigs; D007150:Immunohistochemistry; D007245:Inferior Colliculi / Q000166:cytology / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D017551:Microdialysis; D009419:Nerve Tissue Proteins / Q000032:analysis*; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000159:Vestibulocochlear Nerve / Q000166:cytology / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000032:analysis
D009419:Nerve Tissue Proteins; D016760:Proto-Oncogene Proteins c-fos; D005680:gamma-Aminobutyric Acid