Estradiol and pregnenolone sulfate could modulate PMA-stimulated and Ca2+/calmodulin-dependent synaptosomal membrane protein phosphorylation from rat brain in vivo.
We have examined the effect of two steroids, pregnenolone sulfate and 17-beta-estradiol, on the activity of two protein kinases: protein kinase C and Ca2+/calmodulin-dependent protein kinase. The activity of the kinases was evaluated as phosphorylation of two synapsins Ia and Ib in cerebral cortex and hippocampus of the rat brain. Both steroids decreased phosphorylation of both synapsins to a great extent; however, in hippocampus neither pregnenolone nor estradiol influenced the reaction catalyzed by Ca2+/calmodulin-protein kinase. In the remaining areas of the brain estradiol decreased the activity of both studied kinases to a greater degree than pregnenolone sulfate. Our study suggests that pregnenolone sulfate and 17-beta-estradiol could modulate directly Ca2+/calmodulin-dependent protein kinase and protein kinase C and thus directly influence processes of neurotransmission.
Rebas
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E
II Department of Biochemistry, Medical University of Lodz, Poland.
Lachowicz
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A
Lachowicz
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L
D000818:Animals; D001921:Brain / Q000378:metabolism*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006624:Hippocampus / Q000378:metabolism; D008565:Membrane Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation; D011284:Pregnenolone / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D016704:Synapsins / Q000302:isolation & purification / Q000378:metabolism*; D013574:Synaptosomes / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D008565:Membrane Proteins; D016704:Synapsins; C018370:pregnenolone sulfate; D004958:Estradiol; D011284:Pregnenolone; D011493:Protein Kinase C; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D013755:Tetradecanoylphorbol Acetate