PKC-independent inhibition of glutamate exocytosis by arachidonic acid in rat cerebrocortical synaptosomes.
In rat cerebrocortical synaptosomes, the addition of 4 beta-phorbol dibutyrate (4 beta-PDBu) and arachidonic acid enhances and decreases, respectively, the glutamate release evoked by 4-aminopyridine. Pretreatment of synaptosomes with 12-O-tetradecanoylphorbol 13-acetate (TPA) or pre-incubation with staurosporine, prevent the stimulatory effect of 4 beta-PDBu, but are without effect on the inhibitory action of arachidonic acid. Moreover, methyl arachidonate, which is not effective as a PKC activator, also strongly inhibits glutamate exocytosis. These results suggest that PKC is not involved in the inhibition of glutamate release by arachidonic acid.
Herrero
I
I
Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.
Miras-Portugal
M T
MT
Sánchez-Prieto
J
J
D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000378:metabolism* / Q000648:ultrastructure; D004789:Enzyme Activation; D005089:Exocytosis; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D019311:Staurosporine; D013574:Synaptosomes / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000470:Alkaloids; D001095:Arachidonic Acids; D005971:Glutamates; D018698:Glutamic Acid; D011493:Protein Kinase C; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate