Role of protein kinase C isoenzymes in fatty acid stimulation of insulin secretion.
Although hyperlipidemia is frequently associated with hyperinsulinemia. the stimulation of insulin secretion by fatty acids in the in vitro studies has remained a matter of constant debate, partly because of the uncertainty about a clearly defined mechanism to explain such a direct effect. In this study, we used a pharmacologic approach to test the hypothesis that protein kinase C (PKC) signal-transduction pathway is involved in fatty acid-stimulated insulin secretion. Isolated rat islets were perifused with either palmitate (C(16:0)) or linoleate (C(18:2)) in the absence or presence of selective inhibitors of PKC isoenzymes. Our results suggest a role for Ca2+-independent PKC isoenzymes in the signal transduction of fatty acid-stimulated insulin secretion. The data imply that either the nonconventional and/or atypical isoforms of PKC are involved in the stimulation of insulin release induced by fatty acids.
Littman
E D
ED
Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA.
Pitchumoni
S
S
Garfinkel
M R
MR
Opara
E C
EC
D000818:Animals; D002227:Carbazoles / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005227:Fatty Acids / Q000494:pharmacology*; D005260:Female; D007211:Indoles / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019787:Linoleic Acid / Q000494:pharmacology; D019308:Palmitic Acid / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction
D002227:Carbazoles; D004791:Enzyme Inhibitors; D005227:Fatty Acids; D007211:Indoles; D007328:Insulin; D007527:Isoenzymes; C081021:Go 6976; D019308:Palmitic Acid; D019787:Linoleic Acid; D011493:Protein Kinase C; C064758:Ro 31-8220