Functional glycine receptors (GlyRs) are enriched in the hippocampus, but their roles in synaptic transmission are unclear. In this study, we examined the effect of GlyR activation on paired-pulse stimulation of the whole-cell postsynaptic currents (PSCs) in the Schaffer-CA1 synapses in rat hippocampal slices. Bath application of glycine reduced the amplitude of PSCs, accompanied by all increase ill holding current and resting conductance. Moreover, glycine application increased the paired-pulse ratio (PPR) of PSCs significantly, all effect largely abolished by the GlyR specific antagonist strychnine. Interestingly, glycine application had no significant effect oil either the amplitude or the PPR of excitatory postsynaptic currents (EPSCs). Our findings suggest that GlyR activation regulates hippocampal short-term plasticity by altering GABAergic neurotransmission. (c) 2006 Elsevier Inc. All rights reserved.