Glucagon-Like Peptide-1-(7-36)Amide Is Transformed to Glucagon-Like Peptide-1-(9-36)Amide by Dipeptidyl Peptidase IV in the Capillaries Supplying the L Cells of the Porcine Intestine

Abstract

The insulinotropic hormone glucagon-like peptide-1 (GLP-1) is stored in the intestinal L cell in an active form, GLP-1-(7–36)amide, but more than half of the endogenous peptide circulates in an inactive, N-terminally truncated form, GLP-1-(9–36)amide. This study examined the GLP-1 newly secreted from the porcine ileum, in vitro (isolated perfused preparation) and in vivo (anesthetized pig), to determine where this conversion occurs.