title: Glycine-induced currents are insensitive to the glycine receptor α1 subunit-specific blocker, cyanotriphenylborate, in older circling mice.
abstract: The pharmacologic characteristics of glycine receptors (GlyRs) in the lateral superior olive (LSO) of circling mice, animal model for inherited deafness, were investigated using a GlyR α1 subunit-specific receptor blocker (cyanotriphenylborate [CTB]). There was a statistically significant age-dependent increase in the antagonistic effect of CTB in heterozygous (+/cir) mice. In postnatal (P)0-P3 heterozygous (+/cir) mice, glycine currents evoked by glycine puffs were reduced to 20.4±2.6, 37.1±3.1, and 63.9±2.5% at 0.1, 1, and 10 μM CTB (n=13) compared to controls, while the glycine currents were reduced to 22.3±3.5, 52.9±4.1, and 78.3±3.5% at 0.1, 1, and 10 μM CTB (n=7) in P8-P12 heterozygous (+/cir) mice. In contrast, the antagonistic effect of CTB was not strong and even less than that of younger animals in older homozygous (cir/cir) mice. In P0-P3 homozygous (cir/cir) mice, the extent of inhibition was 20.2±3.7, 37.8±4.3, and 66.8±4.2% at 0.1, 1, and 10 μM CTB (n=6) compared to controls, while the extent of inhibition was 18.7±2.4, 28.1±3.9, and 39.1±8.2% (n=6) in P8-P12 homozygous (cir/cir) mice. The age-dependent decrease in the antagonistic effect of CTB indicates the abnormal development of the α1 subunit-containing GlyRs in homozygous (cir/cir) mice.
authors.affiliation: Department of Nanobio Medical Science, Dankook University, San 29, Anseo-dong, Cheonan-si, Chungnam 330-714, South Korea.
authors.forename: Jonu
authors.initials: J
authors.lastname: Pradhan
authors.forename: Seung Cheol
authors.initials: SC
authors.lastname: Ahn
mesh_terms: D000367:Age Factors; D000818:Animals; D001881:Borates / Q000494:pharmacology*; D003638:Deafness / Q000151:congenital / Q000503:physiopathology*; D004195:Disease Models, Animal; D018756:GABA Antagonists / Q000494:pharmacology; D005998:Glycine / Q000494:pharmacology*; D006720:Homozygote; D051379:Mice; D008817:Mice, Mutant Strains; D010852:Picrotoxin / Q000494:pharmacology; D018009:Receptors, Glycine / Q000037:antagonists & inhibitors* / Q000502:physiology; D013569:Synapses / Q000187:drug effects
chemical_list: D001881:Borates; D018756:GABA Antagonists; D005998:Glycine; D010852:Picrotoxin; D018009:Receptors, Glycine; C089415:cyanotriphenylborate