The effect of monooleoylglycerol on insulin secretion from isolated perifused rat islets.
The effect of monooleoylglycerol on cholecystokinin- and tolbutamide-induced insulin secretion was examined in isolated perifused rat islets. In the presence of 5.5 mmol/l glucose, addition of 10 nmol/l cholecystokinin or 50 mumol/l tolbutamide had practically no effect on insulin secretion. Combined tolbutamide and cholecystokinin led to a biphasic insulin secretory response which was significantly enhanced by addition of 50 mumol/l monooleoylglycerol, an inhibitor of diacylglycerol kinase. Monooleoylglycerol (50 mumol/l) alone had a minimal stimulatory effect on insulin release in the presence of 5.5 mmol/l glucose. Perifusion of islets with 1 mumol/l forskolin had no significant effect on basal insulin secretion in the presence of 5.5 mmol/l glucose, but markedly enhanced the responses to both cholecystokinin plus tolbutamide, and to the combination of cholecystokinin, tolbutamide and monooleoylglycerol. Lowering the glucose level to 2.75 mmol/l abolished the profound stimulatory effect to these agonist combinations on insulin release. Finally, monooleoylglycerol also enhanced the first and second phase insulin secretory responses induced by 20 mmol/l glucose. These results are discussed in relationship to the possible role of protein kinase C in mediating insulin secretion.
Zawalich
W S
WS
Yale University School of Nursing, New Haven, Conn.
Zawalich
K C
KC
Rasmussen
H
H
D000818:Animals; D002766:Cholecystokinin / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D005989:Glycerides / Q000494:pharmacology*; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D014044:Tolbutamide / Q000494:pharmacology
D005989:Glycerides; D007328:Insulin; D005576:Colforsin; D002766:Cholecystokinin; D014044:Tolbutamide; C005953:monoolein; D005947:Glucose