Fast increases of AMPA receptor sensitivity following tetanus-induced potentiation in the CA1 region of the rat hippocampus.
Changes in sensitivity of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) subtype of glutamate receptors following the induction of long-term potentiation (LTP) were investigated in rat hippocampal slices. AMPA was ejected into the stratum radiatum of the hippocampal CA1 region by pressure ejection and the response recorded intracellularly. Responses to AMPA exhibited a fast increase (2-3 min) following LTP induction: the time course of this increase paralleled the potentiation of the excitatory postsynaptic current (EPSC). In cases where there was no increase in the slope of intracellularly recorded EPSC following tetanization, no increase of the AMPA responses was observed. These results suggest that increases in postsynaptic AMPA sensitivity can underlie short-term potentiation (STP) and thus, support a postsynaptic locus for both STP and LTP.
Fedorov
N B
NB
Department of Neurophysiology, Federal Institute for Neurobiology, Magdeburg, Germany.
Brown
R E
RE
Reymann
K G
KG
D000818:Animals; D006624:Hippocampus / Q000187:drug effects*; D017774:Long-Term Potentiation / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000187:drug effects / Q000502:physiology*; D012680:Sensitivity and Specificity; D013742:Tetanus / Q000503:physiopathology*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology*
D018091:Receptors, AMPA; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid