Pairing of pre- and postsynaptic activities in hippocampal CA1 neurons induces long-term modifications of NMDA receptor-mediated synaptic potential.
An in vitro slice preparation of rat hippocampus was used to study the long-term modifications of pharmacologically isolated N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic potential (EPSPNMDA). Intracellular recordings were made from CA1 pyramidal cells in the presence of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 10 microM) and picrotoxin (50 microM) which block non-NMDA and GABAA receptors, respectively. Pairing of low-frequency EPSPNMDA with postsynaptic depolarization induced a long-term depression (LTD) of EPSPNMDA. The maximal reduction of EPSPNMDA amplitude amounted to 81.3% of the control 1 min after the pairing. When low-frequency synaptic stimulation was paired with strong postsynaptic depolarization, a long-term potentiation (LTP) of EPSPNMDA could be induced. These results suggest that the induction of long-term modifications of EPSPNMDA has at least a postsynaptic component.
Lin
J H
JH
Department of Pharmacology, College of Medicine, National Cheng-Kung University, Tainan, Taiwan.
Way
L J
LJ
Gean
P W
PW
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D000818:Animals; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008839:Microelectrodes; D009473:Neuronal Plasticity / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D009475:Neurons, Afferent / Q000187:drug effects; D010852:Picrotoxin / Q000494:pharmacology; D011810:Quinoxalines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000502:physiology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology*
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D010852:Picrotoxin; D011810:Quinoxalines; D016194:Receptors, N-Methyl-D-Aspartate