Activation of protein kinase C is not required for glyceraldehyde-stimulated insulin secretion from rat islets.

Glyceraldehyde-induced insulin release from rat islets of Langerhans was not affected following down-regulation of protein kinase C (PKC) by prolonged exposure to the tumour-promoting phorbol ester, 4 beta-phorbol myristate acetate (PMA). Glyceraldehyde did not cause translocation of islet PKC under conditions in which PMA stimulated redistribution of enzyme activity. These results indicate that activation of PKC is not required for glyceraldehyde stimulation of insulin secretion from normal rat islets.