EFFECTS OF GLUCAGON-LIKE PEPTIDE-1(7-36)AMIDE ON THE CONCENTRATIONS OF INSULIN AND GLUCOSE IN SHEEP

1. The effects of glucagon-like peptide-1(7-36)amide (GLP-1) and/or gl ucose on the concentration of insulin in fed and starved sheep were st udied. Insulin concentrations in starved sheep increased with increasi ng doses of GLP-1 (0.23-2.27 nmol) when given together with glucose. 2 . Hyperglycaemia was necessary for GLP-1 to stimulate increases in ser um insulin but the level required was low (0.4 mmol/l or less). 3. In fed sheep hyperglycaemia alone caused an increase in serum insulin. 4. GLP-1 improved the ability of both fed and starved sheep to remove ex ogenous glucose from the circulation. 5. GLP-1 did not augment insulin secretion in response to other known insulin secretagogues.