title: Auditory deficits of Kcna1 deletion are similar to those of a monaural hearing impairment.
abstract: Kv1.1 subunits of low voltage-activated (Kv) potassium channels are encoded by the Kcna1 gene and crucially determine the synaptic integration window to control the number and temporal precision of action potentials in the auditory brainstem of mammals and birds. Prior electrophysiological studies showed that auditory signaling is compromised in monaural as well as in binaural neurons of the auditory brainstem in Kv1.1 knockout mice (Kcna1(-/-)). Here we examine the behavioral effects of Kcna1 deletion on sensory tasks dependent on either binaural processing (detecting the movement of a sound source across the azimuth), monaural processing (detecting a gap in noise), as well as binaural summation of the acoustic startle reflex (ASR). Hearing thresholds measured by auditory brainstem responses (ABR) do not differ between genotypes, but our data show a much stronger performance of wild type mice (+/+) in each test during binaural hearing which was lost by temporarily inducing a unilateral hearing loss (through short term blocking of one ear) thus remarkably, leaving no significant difference between binaural and monaural hearing in Kcna1(-/-) mice. These data suggest that the behavioral effect of Kv1.1 deletion is primarily to impede binaural integration and thus to mimic monaural hearing.
authors.affiliation: Carl-Ludwig-Institute for Physiology, University of Leipzig, Medical School, Germany.
authors.forename: Anita
authors.initials: A
authors.lastname: Karcz
authors.affiliation: Department of Neurobiology and Anatomy, School of Medicine & Dentistry, University of Rochester, NY, USA.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Allen
authors.affiliation: Department of Communication Sciences and Disorders, University of South Florida, 4202 Fowler Av., Tampa, Fl 32620, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Walton
authors.affiliation: Department of Neurobiology and Anatomy, School of Medicine & Dentistry, University of Rochester, NY, USA; Department of Brain & Cognitive Sciences, University of Rochester, NY, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Ison
authors.affiliation: Department of Biology II, Ludwig-Maximilians-University, Munich, Germany. Electronic address: cks@bio.lmu.de.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Kopp-Scheinpflug
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001306:Auditory Pathways / Q000503:physiopathology; D001307:Auditory Perception / Q000235:genetics; D001309:Auditory Threshold; D001522:Behavior, Animal; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D005838:Genotype; D006309:Hearing / Q000235:genetics; D006311:Hearing Disorders / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D051662:Kv1.1 Potassium Channel / Q000172:deficiency* / Q000235:genetics; D008297:Male; D008809:Mice, Inbred C3H; D018345:Mice, Knockout; D010641:Phenotype; D011571:Psychoacoustics; D013216:Reflex, Startle; D017603:Signal Detection, Psychological; D013017:Sound Localization; D013997:Time Factors
chemical_list: C496947:Kcna1 protein, mouse; D051662:Kv1.1 Potassium Channel