GLP-1(7-36)amide-stimulated insulin secretion in rat islets is sodium-dependent.
We examined the Na(+)-dependency of the effects of GLP-1(7-36)amide in normal, overnight cultured rat islets. It was found that GLP-1(7-36)amide stimulated insulin secretion, 45Ca(2+)-efflux, and 86Rb(+)-efflux from prelabelled islets. All these effects were abolished by omitting Na+ from the medium and replacing it with N-methyl-glucamine. This suggests that GLP-1(7-36)amide stimulates insulin secretion by depolarizing the beta-cells by increasing their permeability to Na+.
Fridolf
T
T
Department of Pharmacology, Lund University, Sweden.
Ahrén
B
B
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D005934:Glucagon / Q000494:pharmacology; D052216:Glucagon-Like Peptide 1; D004763:Glucagon-Like Peptides; D005947:Glucose / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology*; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012413:Rubidium / Q000378:metabolism; D012964:Sodium / Q000494:pharmacology*
D007328:Insulin; D010446:Peptide Fragments; D010455:Peptides; C055453:glucagon-like peptide 1 (7-36)amide; D004763:Glucagon-Like Peptides; D052216:Glucagon-Like Peptide 1; D005934:Glucagon; D012964:Sodium; D005947:Glucose; D012413:Rubidium; D002118:Calcium