Scopolamine attenuates tinnitus-related plasticity in the auditory cortex.
High doses of salicylate induce a temporary hearing deficit and a temporary subjective tinnitus in humans and animals. In animals, salicylate suppresses activity in the ascending auditory system but generates activity and plasticity in the auditory cortex and central amygdala. In addition to changes in the auditory system evoked by hearing impairment, enhanced stress may be crucial for the salicylate-induced alterations in the auditory cortex. The central amygdala responds to stress, and may influence cortical excitability and plasticity through cholinergic mechanisms. We investigated whether salicylate-induced plasticity in the auditory cortex is prevented by blocking cortical cholinergic receptors with the muscarinic antagonist scopolamine. Scopolamine suppresses salicylate-induced plasticity in the auditory cortex and, therefore, may be effective in suppressing the tinnitus sensation.
Wallhäusser-Franke
Elisabeth
E
Department of Neuroacoustics, Institute of Zoology, Darmstadt University of Technology, Darmstadt, Germany. wallhaeusser-franke@t-online.de
Cuautle-Heck
Bessy
B
Wenz
Gabriele
G
Langner
Gerald
G
Mahlke
Claudia
C
D000818:Animals; D001303:Auditory Cortex / Q000187:drug effects / Q000473:pathology*; D002452:Cell Count; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005849:Gerbillinae; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D018727:Muscarinic Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009473:Neuronal Plasticity / Q000187:drug effects*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D012459:Salicylates; D012601:Scopolamine / Q000494:pharmacology* / Q000627:therapeutic use; D014012:Tinnitus / Q000139:chemically induced / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology*
D004338:Drug Combinations; D018727:Muscarinic Antagonists; D009419:Nerve Tissue Proteins; D016760:Proto-Oncogene Proteins c-fos; D012459:Salicylates; D012601:Scopolamine