Enhancement of glucagon secretion from isolated rat islets of Langerhans by phorbol 12-myristate 13-acetate.
The phorbol ester 4 beta-phorbol 12-myristate 13-acetate (PMA), at concentrations of 0.1 microM and above, stimulated secretion of glucagon and of insulin from isolated rat islets of Langerhans incubated in the presence of 5.5 mM-glucose. Stimulation of secretion of both hormones by 1 microM-PMA persisted in the absence of external Ca2+, and could be abolished by incubating the islets at 4 degrees C. These findings suggest a role of protein kinase C in the alpha-cell (and beta-cell) secretory mechanism.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D005934:Glucagon / Q000378:metabolism*; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010704:Phorbols / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013696:Temperature; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D007328:Insulin; D010704:Phorbols; D005934:Glucagon; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium