Effects of cisapride on the secretion of pancreatic polypeptide in healthy volunteers.

Plasma human pancreatic polypeptide (hPP) responses to intravenous injections of a new gastric and intestinal motility promoting agent, R51 619 (cisapride), were studied in healthy volunteers. The mean fasting concentrations of plasma hPP (39 +/- 5.4 pg/ml; mean +/- S.E.) were elevated significantly to the peak values of 118 +/- 25.1 pg/ml 30 min after the drug had been given in a dose of 4 mg over 5 min. However, plasma insulin (IRI), glucose and prolactin levels were not elevated. Atropine diminished the cisapride-induced hPP elevation, thereby suggesting that cisapride induced release of acetylcholine but had no antidopaminergic action.