Long-lasting decreases of AMPA responses following postsynaptic activity in single hippocampal neurons.
Direct postsynaptic depolarization and firing of single CA1 neurons caused decreased responses to iontophoresed alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA). Since there was no associated change in the excitatory postsynaptic potential (EPSP) evoked by electrical stimulation in the same band of stratum radiatum, we infer that the decreased AMPA response was mediated predominantly by extrasynaptic receptors. The decreased AMPA response developed within 10-30 min after conditioning, a time course similar to the delayed increase in AMPA responses associated with long-term potentiation (LTP) [Davies et al. (1989), Nature, 338:500-503; Sergueeva et al. (1993), Neuropharmacology, 32:933-935]. Our observations suggest the existence of mirror-image processes that may regulate AMPA receptors and possibly synaptic efficacy.
Vickery
R M
RM
Department of Physiology, University College London, UK.
Bindman
L J
LJ
D000818:Animals; D006624:Hippocampus / Q000187:drug effects*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D009435:Synaptic Transmission / Q000187:drug effects*; D013997:Time Factors; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology*
D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid