Synergistic potentiation of glutamate release by arachidonic acid and oleoyl-acetyl-glycerol.
Both the activation of protein kinase C (PKC) and the facilitation of depolarization-evoked glutamate release have been implicated in the induction of hippocampal long-term synaptic potentiation. These observations may be functionally related, since stimulation of PKC activity enhances evoked glutamate release. Recently, it was shown that arachidonic acid and the diacylglycerol analog oleoyl-acetyl-glycerol activate brain PKC in a synergistic fashion. We report the facilitation of depolarization-induced glutamate efflux from hippocampal mossy fiber synaptosomes due to a combination of arachidonic acid and oleoyl-acetyl-glycerol. The potentiating effects appeared to depend on the activation of PKC since they were attenuated by staurosporine. In addition, the effects of arachidonic acid and oleoyl-acetyl-glycerol appeared to be limited to calcium-dependent processes.
Zhang
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Department of Biological Sciences, Kent State University, OH 44242.
Dorman
R V
RV
D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology*; D004075:Diglycerides / Q000494:pharmacology*; D004357:Drug Synergism; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D006624:Hippocampus / Q000378:metabolism*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D051381:Rats; D017207:Rats, Sprague-Dawley; D019311:Staurosporine; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology
D000470:Alkaloids; D004075:Diglycerides; D005971:Glutamates; D016718:Arachidonic Acid; D018698:Glutamic Acid; C038237:1-oleoyl-2-acetylglycerol; D011493:Protein Kinase C; D019311:Staurosporine; D011188:Potassium