title: Differential distribution of glycine receptor subtypes at the rat calyx of Held synapse.
abstract: The properties of glycine receptors (GlyRs) depend upon their subunit composition. While the prevalent adult forms of GlyRs are heteromers, previous reports suggested functional α homomeric receptors in mature nervous tissues. Here we show two functionally different GlyRs populations in the rat medial nucleus of trapezoid body (MNTB). Postsynaptic receptors formed α1/β-containing clusters on somatodendritic domains of MNTB principal neurons, colocalizing with glycinergic nerve endings to mediate fast, phasic IPSCs. In contrast, presynaptic receptors on glutamatergic calyx of Held terminals were composed of dispersed, homomeric α1 receptors. Interestingly, the parent cell bodies of the calyces of Held, the globular bushy cells of the cochlear nucleus, expressed somatodendritic receptors (α1/β heteromers) and showed similar clustering and pharmacological profile as GlyRs on MNTB principal cells. These results suggest that specific targeting of GlyR β-subunit produces segregation of GlyR subtypes involved in two different mechanisms of modulation of synaptic strength.
authors.affiliation: Department of Auditory Neuroscience, Institute of Experimental Medicine ASCR, 14220 Prague, Czech Republic.
authors.forename: Bohdana
authors.initials: B
authors.lastname: Hruskova
authors.forename: Johana
authors.initials: J
authors.lastname: Trojanova
authors.forename: Akos
authors.initials: A
authors.lastname: Kulik
authors.forename: Michaela
authors.initials: M
authors.lastname: Kralikova
authors.forename: Kateryna
authors.initials: K
authors.lastname: Pysanenko
authors.forename: Zbynek
authors.initials: Z
authors.lastname: Bures
authors.forename: Josef
authors.initials: J
authors.lastname: Syka
authors.forename: Laurence O
authors.initials: LO
authors.lastname: Trussell
authors.forename: Rostislav
authors.initials: R
authors.lastname: Turecek
mesh_terms: D000818:Animals; D001306:Auditory Pathways / Q000378:metabolism*; D049229:Dendritic Spines / Q000502:physiology; D004558:Electric Stimulation; D055724:Electrophysiological Phenomena; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D005998:Glycine / Q000502:physiology; D018684:Glycine Agents / Q000494:pharmacology; D007150:Immunohistochemistry; D007700:Kinetics; D016253:Microscopy, Immunoelectron; D009411:Nerve Endings / Q000378:metabolism; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D018009:Receptors, Glycine / Q000187:drug effects / Q000378:metabolism*; D017661:Receptors, Presynaptic / Q000378:metabolism; D013569:Synapses / Q000378:metabolism*
chemical_list: D018684:Glycine Agents; D018009:Receptors, Glycine; D017661:Receptors, Presynaptic; D005998:Glycine