Comparative effects of caerulein on food intake and pancreatic secretion in dogs

We compared effects of the CCK analog caerulein on feeding and pancreatic secretion. Nine fasted mongrel dogs with gastric and pancreatic fistulas received scalar doses of caerulein (0, 6.25, 12.5, 25, 50, 100, 200, 400 pmol/kg-hr, each for 30 min). The D50 dose for stimulation of pancreatic secretion was 15 pmol/kg-hr. Effects of intravenous caerulein (0 to 800 pmol/kg-hr; 15 min before and during a 45 min test meal) on food intake were examined in 8 beagles under 4 feeding conditions: 1 meal/day (22 hr fast), 2 meals/day (4 hr fast), 2 meals/day (19 hr fast), and after ad lib access to food followed by a 4 hr fast. The lowest doses that inhibited feeding were: 400 pmol/kg-hr for feeding condition, 200 pmol/kg-hr for and, and 150 pmol/kg-hr for. We conclude: the potency of caerulein for inhibition of food intake is dependent upon feeding condition; these results do not support a role for CCK as a satiety hormone, since the lowest dose of caerulein for inhibition of feeding was 10 times larger than the D50 dose of caerulein for stimulation of pancreatic secretion.