title: Deficit in acoustic signal-in-noise detection in glycine receptor α3 subunit knockout mice.
abstract: Hearing is an essential sense for communication in animals and humans. Normal function of the cochlea of higher vertebrates relies on a fine-tuned interplay of afferent and efferent innervation of both inner and outer hair cells. Efferent inhibition is controlled via olivocochlear feedback loops, mediated mainly by acetylcholine, γ-aminobutyric acid (GABA) and glycine, and is one of the first sites affected by synapto- and neuropathy in the development of hearing loss. While the functions of acetylcholine, GABA and other inhibitory transmitters within these feedback loops are at least partially understood, especially the function of glycine still remains elusive. To address this question, we investigated hearing in glycine receptor (GlyR) α3 knockout (KO) and wildtype (WT) mice. We found no differences in pure tone hearing thresholds at 11.3 and 16 kHz between the two groups as assessed by auditory brainstem response (ABR) measurements. Detailed analysis of the ABR waves at 11.3 kHz, however, revealed a latency decrease of wave III and an amplitude increase of wave IV in KO compared to WT animals. GlyRα3 KO animals showed significantly impaired prepulse inhibition of the auditory startle response in a noisy environment, indicating that GlyRα3-mediated glycinergic inhibition is important for signal-in-noise detection.
authors.affiliation: Experimental Otolaryngology, ENT Hospital Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Waldstrasse 1, 91054, Erlangen, Germany.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Tziridis
authors.affiliation: Experimental Otolaryngology, ENT Hospital Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Waldstrasse 1, 91054, Erlangen, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Buerbank
authors.affiliation: Institute of Biochemistry, Emil-Fischer-Zentrum, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Eulenburg
authors.affiliation: Department of Otorhinolaryngology, Saarland University Hospital, Homburg/Saar, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Dlugaiczyk
authors.affiliation: Experimental Otolaryngology, ENT Hospital Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Waldstrasse 1, 91054, Erlangen, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Schulze
mesh_terms: D000818:Animals; D001309:Auditory Threshold; D016057:Evoked Potentials, Auditory, Brain Stem; D018072:Hair Cells, Auditory, Outer / Q000378:metabolism / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011930:Reaction Time; D018009:Receptors, Glycine / Q000235:genetics* / Q000378:metabolism; D012022:Reflex, Acoustic; D013216:Reflex, Startle
chemical_list: D018009:Receptors, Glycine; C113965:glycine receptor alpha3 subunit
keywords: acoustic startle response; auditory brainstem response; prepulse inhibition; rodent