Excitatory amino acid receptors involved in primary afferent-evoked polysynaptic EPSPs of substantia gelatinosa neurons in the adult rat spinal cord slice.
Intracellular recordings were made from substantia gelatinosa (SG) neurons in spinal cord slices to determine a subclass of excitatory amino acid receptors involved in polysynaptic excitatory postsynaptic potentials (EPSPs). In the majority of neurons, polysynaptic EPSPs evoked by A delta fiber were not affected by 2-amino-5-phosphonovaleric acid (APV), while all EPSPs including monosynaptic EPSPs were depressed by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). All spontaneous EPSPs were blocked by CNQX, while spontaneous EPSPs in a few SG neurons were attenuated by APV. These observations suggest that polysynaptic EPSPs evoked through A delta fibers are predominantly mediated by activation of the non-N-methyl-D-aspartate (non-NMDA) receptor subclass.
Department of Physiology, Kurume University School of Medicine, Japan.
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Yoshimura
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Nishi
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D005071:Evoked Potentials / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011810:Quinoxalines / Q000494:pharmacology; D051381:Rats; D018091:Receptors, AMPA; D017459:Receptors, Amino Acid / Q000502:physiology*; D017470:Receptors, Glutamate / Q000187:drug effects / Q000502:physiology*; D018092:Kainic Acid Receptors; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology; D013376:Substantia Gelatinosa / Q000166:cytology / Q000502:physiology*
D015763:2-Amino-5-phosphonovalerate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D011810:Quinoxalines; D018091:Receptors, AMPA; D017459:Receptors, Amino Acid; D017470:Receptors, Glutamate; D018092:Kainic Acid Receptors; D016194:Receptors, N-Methyl-D-Aspartate