The Glutamatergic and Gabaergic Transmitter System in the Rat Nucleus Accumbens: An Electrophysiological in Vitro Study
In this study, postsynaptic potentials elicited by local stimulation or stimulation of the corpus callosum were investigated by extra- and intracellular recordings in slices of the rat Nucleus Accumbens (Acb). In extracellular recordings, the postsynaptic response consisted of a population spike and a mixed EPSP-IPSP component. This response was strongly and reversibly antagonized by quisqualate/kainate (Q/K) receptor antagonists but not by acetylcholine, dopamine and enkephalin antagonists. In intracellular recordings the predominant role of Q/K receptors in mediating the synaptic response was confirmed. In addition, a small NMDA receptor mediated component was found which contributed to the late phase of the EPSP. Application of a GABA(A) antagonist particularly enhanced and prolonged the NMDA receptor mediated component of the synaptic response. The relevance of these findings for studying the role of the Acb in regulating locomotor activity is discussed.
KeywordsNMDA Receptor Nucleus Accumbens Rest Membrane Potential Intracellular Recording Population Spike
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