title: Glycinergic input of widefield, displaced amacrine cells of the mouse retina.
abstract: Glycine receptors (GlyRs) of displaced amacrine cells of the mouse retina were analysed using whole cell recordings and immunocytochemical staining with subunit-specific antibodies. During the recordings the cells were filled with a fluorescent tracer and 11 different morphological types could be identified. The studies were performed in wild-type mice and in mutant mice deficient in the GlyRalpha1 (Glra1(spd-ot), 'oscillator' mouse), the GlyRalpha2 (Glra2(-/-)) and the GlyRalpha3 subunit (Glra3(-/-)). Based on their responses to the application of exogenous glycine in the retinas of wild-type and mutant mice, the cells were grouped into three major classes: group I cells (comprising the morphological types MA-S5, MA-S1, MA-S1/S5, A17, PA-S1, PA-S5 and WA-S1), group II cells (comprising the morphological types PA-S4, WA-S3 and WA-multi) and ON-starburst cells. For further analysis, spontaneous inhibitory postsynaptic currents (sIPSCs) were measured both in wild-type and mutant mouse retinas. Glycinergic sIPSCs and glycine induced currents of group I cells remained unaltered across wild-type and the three mutant mice (mean decay time constant of sIPSCs, tau approximately 25 ms). Group II cells showed glycinergic sIPSCs and glycine induced currents in wild-type, Glra1(spd-ot) and Glra3(-/-) mice (tau approximately 25 ms); however, glycinergic currents were absent in group II cells of Glra2(-/-) mice. Glycine induced currents and sIPSCs recorded from ON-starburst amacrine cells did not differ significantly between wild-type and the mutant mouse retinas (tau approximately 50-70 ms). We propose that GlyRs of group II cells are dominated by the alpha2 subunit; GlyRs of ON-starburst amacrine cells appear to be dominated by the alpha4 subunit.
authors.affiliation: Max-Planck-Institut für Hirnforschung, Deutschordenstr. 46, D-60528 Frankfurt/Main, Germany.
authors.forename: Sriparna
authors.initials: S
authors.lastname: Majumdar
authors.forename: Jan
authors.initials: J
authors.lastname: Weiss
authors.forename: Heinz
authors.initials: H
authors.lastname: Wässle
mesh_terms: D025042:Amacrine Cells / Q000187:drug effects* / Q000378:metabolism*; D000818:Animals; D003712:Dendrites / Q000473:pathology; D005998:Glycine / Q000494:pharmacology*; D018684:Glycine Agents / Q000494:pharmacology*; D053444:Inhibitory Postsynaptic Potentials / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018408:Patch-Clamp Techniques; D018009:Receptors, Glycine / Q000235:genetics / Q000378:metabolism*; D012160:Retina / Q000166:cytology / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism; D013997:Time Factors
chemical_list: C501173:Glra2 protein, mouse; D018684:Glycine Agents; D018009:Receptors, Glycine; C113965:glycine receptor alpha3 subunit; C408089:glycine receptor, alpha4-subunit; D005998:Glycine