title: Long-term potentiation of silent synapses in substantia gelatinosa neurons.
abstract: In this study, we observed quantal changes in single synapse excitatory postsynaptic currents to characterize N-methyl-D-aspartate receptor-mediated silent synapses between primary afferents and spinal substantia gelatinosa neurons. The failure rate of primary afferent quantal excitatory postsynaptic currents was lower at depolarized holding potentials than at hyperpolarized potentials. This lower failure rate at depolarized potentials was due to the activation of N-methyl-D-aspartate receptor-mediated excitatory postsynaptic currents. Pairing primary afferents with the postsynaptic depolarization induced a long-term decrease in the failure rate of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor-mediated excitatory postsynaptic currents, but did not alter the failure rate of N-methyl-D-aspartate receptor-mediated excitatory postsynaptic currents. Our findings suggest that pairing primary afferent with postsynaptic depolarization can convert silent substantia gelatinosa synapses to active synapses and the mechanism of this synaptic plasticity is associated with postsynaptic modification.
authors.affiliation: Department of Physiology and Biophysics, Seoul National University College of Medicine, Seoul 110-799, South Korea.
authors.forename: Sung Jun
authors.initials: SJ
authors.lastname: Jung
authors.forename: Yu Shin
authors.initials: YS
authors.lastname: Kim
authors.forename: Dong Kwan
authors.initials: DK
authors.lastname: Kim
authors.forename: Jun
authors.initials: J
authors.lastname: Kim
authors.forename: Sang Jeong
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D002614:Chelating Agents / Q000494:pharmacology; D004307:Dose-Response Relationship, Radiation; D004347:Drug Interactions; D004533:Egtazic Acid / Q000494:pharmacology; D004558:Electric Stimulation / Q000379:methods; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D018698:Glutamic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D008274:Magnesium / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013376:Substantia Gelatinosa / Q000166:cytology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
chemical_list: D002614:Chelating Agents; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D018698:Glutamic Acid; D004533:Egtazic Acid; D016202:N-Methylaspartate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D008274:Magnesium