Role of glial and neuronal glycine transporters in the control of glycinergic and glutamatergic synaptic transmission in lamina X of the rat spinal cord

摘要: Using whole cell voltage clamp recordings from lamina X neurones in rat spinal cord slices, we investigated the effect of glycine transporter (GlyT) antagonists on both glycinergic inhibitory postsynaptic current (IPSCs) and glutamatergic excitatory (EPSCs). We used ORG 24598 25543, selective glial GlyT (GlyT1) neuronal (GlyT2), respectively. In rats (P12–P16) presence kynurenic acid, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) bicuculline, 25543 applied individually at a concentration 10 μm induced mean inward −10/−50 pA −60 mV increased significantly decay time constants miniature (mIPSCs), spontaneous (sIPSCs) electrically evoked (eIPSCs) currents. but not 24598, decreased frequency mIPSCs sIPSCs. Replacing extracellular sodium with N-methyl-d-glucamine or superfusing slice micromolar concentrations also constant IPSCs. By contrast, constant, amplitude GABAergic IPSCs recorded strychnine were affected by 25543. strychnine, bicuculline CNQX, NMDA receptor-mediated EPSCs (eEPSCs). eEPSCs suppressed 30 μmd-2-amino-5-phosphonovalerate (APV), an antagonist receptor, dichlorokynurenic acid (DCKA), site receptor. Glycine (1–5 μm) d-serine (10 whereas l-serine had no effect. without affecting non-NMDA eEPSCs. conclude that blocking and/or transporters level which turn prolonged duration synaptic potentiated NMDA-mediated response.