CARDIOVASCULAR AND PANCREATIC ENDOCRINE RESPONSES TO GLUCAGON-LIKE PEPTIDE-1(7-36) AMIDE IN THE CONSCIOUS CALF

Intravenous infusions of glucagon-like peptide-1(7-36) amide (CLP-1; 3 5 pmol min(-1) kg(-1) for 10 min) produced a significant rise in mean heart rate, without significant change in mean aortic blood pressure, together with a significant rise in mean arterial plasma insulin, but not in plasma pancreatic glucagon or pancreatic polypeptide concentrat ion, in conscious calves given exogenous glucose (30-60 mu mol min(-1) kg(-1) I.V.). The insulinotropic effect was eliminated in the presenc e of exogenous amino acids (0.03 mmol min(-1) kg(-1) I.V.). It was not affected predictably by blocking the synthesis of nitric oxide or by the simultaneous administration of the established incretin factor gas trin-releasing peptide (GRP). Whereas GLP-1 produced a statistically s ignificant rise in plasma insulin concentration in these animals, it w as much less effective than GRP in this respect, when given by continu ous I.V. infusion.