Thr28, Nle31 CCK-9--an useful CCK analogue in stimulation tests of pancreatic exocrine function.

In the present study we examined the effect of Thr28 Nle31-CCK 25-33 (CCK-9) on pancreatic exocrine function in man. In subjects without pancreatic disease CCK-9 together with i.v. secretin (0.5 CU/kg/h) elicited a maximal stimulation of amylase output at a dose of 10 pmol/kg/h while trypsin and chymotrypsin were stimulated maximally at a dose of 30 pmol/kg/h. Higher doses of 60 and 100 pmol/kg/h had no additional effects. Lipase secretion was stimulated by secretin alone with no additional effect of CCK-9. During all doses of CCK-9 no side effects were observed. In patients with chronic pancreatitis a dose of 30 pmol/kg/h was also sufficient to obtain maximal enzyme output. In conclusion this derivative of CCK can be considered as a potent and useful alternative to amphibian caerulein in direct pancreatic function tests.