Modulation of DL-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)/quisqualate receptors by phospholipase A2 treatment.
The expression of long-term potentiation (LTP) in area CA1 of hippocampus has been proposed to result from an increased sensitivity of the AMPA/quisqualate receptors. We have investigated the binding properties of excitatory amino acid receptors in phospholipase A2 (PLA2)-treated rat brain membranes. PLA2 from bee venom produced a significant increase in the binding of [3H]-AMPA ([3H]-amino-3-hydroxy-5-methylisoxazole-4- propionate), a ligand for the AMPA/quisqualate receptor. Analysis of the saturation kinetics revealed that PLA2 treatment increased the affinity of the AMPA/quisqualate receptor without changing the maximum number of sites. In contrast, PLA2 treatment did not detectably modify the binding of [3H]-kainate to the kainate receptor and of [3H]-glutamate and [3H]-glycine to the NMDA (N-methyl-D-aspartate) receptor complex. These finding suggest that phospholipase A2 may regulate the AMPA/quisqualate receptor and could play an important role in the development of LTP.
Massicotte
G
G
Program in Neural, Informational, and Behavioral Sciences, University of Southern California, Los Angeles 90089.
Baudry
M
M
D000818:Animals; D005971:Glutamates / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects*; D007051:Ibotenic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D007608:Kainic Acid / Q000378:metabolism; D008297:Male; D010741:Phospholipases A / Q000494:pharmacology*; D054467:Phospholipases A2; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D018091:Receptors, AMPA; D017981:Receptors, Neurotransmitter / Q000187:drug effects*; D013570:Synaptic Membranes / Q000187:drug effects; D014316:Tritium; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
D005971:Glutamates; D018091:Receptors, AMPA; D017981:Receptors, Neurotransmitter; D014316:Tritium; D007051:Ibotenic Acid; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D010741:Phospholipases A; D054467:Phospholipases A2; D007608:Kainic Acid; D005998:Glycine