Differential distribution of glycine receptor subtypes at the rat calyx of held synapse
21.11.2012
Hruskova B, Trojanova J, Kulik A, Kralikova M, Pysanenko K, Bures Z, Syka J, Trussell LO, Turecek R.
J Neurosci. 2012;32(47):17012-24.
Properties of gylcine receptors depend upon their subunit composition. While the prevalent adult forms of receptors are heteromers, previous reports suggested functional alpha homomeric receptors. We show two funcionally different
receptor populations in MNTB. Postsynaptic receptors formed alpha1/beta containing clusters on somatodendritic domains of MNTB principal neurons, co-localizing with glycinergic boutons, to mediate fast, phasic IPSCs. By contrast,
presynaptic receptors on glutamatergic calyx of Held terminals were composed of dispersed, homomeric alpha1 receptors. The parent cell bodies of the calyces of Held, the globular bushy cells of the cochlear nucles, expressed somatodendritic receptors and showed similar clustering and pharmacological profiles as glycine receptors on MNTB principal cells. These results suggest that specific targeting of gylcine receptor beta subunit produces segregation of receptor subtypes involved in two different mechanisms of modulation of synaptic strength.
