Comparative effects of amylin and cholecystokinin on food intake and gastric emptying in rats

Veterans Affairs Medical Center, Omaha 68105; Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178; and Arvid Wretlind Laboratory for Metabolic Research, Department of Surgery, Karolinska Institutet at Huddinge University Hospital, S-14186 Stockholm, Sweden CCK is a physiological inhibitor of gastric emptying and food intake. The pancreatic peptide amylin exerts similar actions, yet its physiological importance is uncertain. Objectives were to compare the dose-dependent effects of intravenous infusion of amylin and CCK-8 on gastric emptying and food intake in rats, and to assess whether physiological doses of amylin are effective. Amylin and CCK-8 inhibited gastric emptying with mean effective doses (ED 50 s) of 3 and 35 pmol · kg 1 · min 1 and maximal inhibitions of 60 and 65%, respectively. Amylin and CCK-8 inhibited food intake with ED 50 s of 8 and 14 pmol · kg 1 · min 1 and maximal inhibitions of 78 and 69%, respectively. The minimal effective amylin dose for each effect was 1 pmol · kg 1 · min 1 . Our previous work suggests that this dose increases plasma amylin by an amount comparable to that produced by a meal. These results support the hypothesis that amylin acts as a hormonal signal to the brain to inhibit gastric emptying and food intake and that amylin produces satiety in part through inhibition of gastric emptying. meal patterns; satiety; stomach; intravenous; potency; efficacy