Effect of intraluminal administration of amino acids upon plasma glicentin

To see what effect intraluminal amino acids would have on glicentin secretion, we put a mixture of 10 amino acids (1 g/kg) into the duodenum of five normal, conscious piglets. Their plasma nitrogen rose, as did insulin and glucagon measured with C-terminal-specific antiserum. Plasma total immunoreactive glucagon, determined with non-specific antiserum, rose from 2753 ± 460 pg/ml to a peak of 4434 ± 1352 pg/ml at 30 min. Plasma glicentin, determined with R 64 antiserum, rose from a fasting level of 297 ± 70 pmol/l to a peak of 702 ± 167 pmol/l at 45 min. We also gave oral arginine to 6 pancreatectomized dogs to investigate why the plasma glicentin rises after amino acid ingestion. Arginine raised the plasma total immunoreactive glucagon from 1120 ± 214 pg/ml to a peak of 2266 ± 512 pg/ml at 45 min. We conclude that intraluminally administered amino acids enhance glicentin secretion from the gut.