Glycine-gated Cl- channels underlying synaptic currents.

Glycine receptor Cl- channels underlying inhibitory synaptic currents (IPSCs) were characterized with patch clamp methods applied to thin slices of rat spinal cord. The channels had multiple conductance states with their mean open time being similar to the mean decay time constant of IPSCs. During postnatal development, channel open time became gradually shorter, concomitantly with the decay time of IPSCs. Single channel currents of alpha-homomeric glycine receptors expressed in Xenopus oocytes from cRNAs showed that the adult type receptor had much faster kinetics than the fetal one. It is suggested that the molecular switching of glycine receptor alpha subunits accelerate the time course of inhibitory synaptic responses.