EFFECT OF GLUCAGON-LIKE PEPTIDE-1 ON BIOSYNTHETIC ACTIVITY IN RAT PANCREATIC-ISLETS EXPOSED TO D-GLUCOSE AND THE DIMETHYL ESTER OF SUCCINICACID

It was recently reported that glucagon-like peptide 1 (GLP-1) markedly enhances insulin release evoked by succinic acid dimethyl ester (SAD) . We have now examined the effect of GLP-1 on protein biosynthesis in rat pancreatic islets exposed to SAD (10 mM). In the absence of GLP-1, the ester stimulated the incorporation of L-[4-H-3]phenylalanine into islet protein above the level found in islets exposed to a low concen tration of D-glucose (2.8 mM). In both cases, however, GLP-1 failed to enhance protein biosynthesis significantly. Thus, GLP-1, whilst enhan cing nutrient-stimulated insulin release, does not increase the effect of D-glucose or other nutrient secretagogues on the biosynthetic acti vity of islet cells.