CERULEIN-INDUCED CHANGES IN PLASMA AMINO-ACID-CONCENTRATIONS ARE NOT A VALID TEST FOR PANCREATIC INSUFFICIENCY

Objectives: There is controversy about the cholecystokinin (CCK)-induc ed decrease of plasma amino acids for the diagnosis of pancreatic insu fficiency in that it is unclear whether the conflicting results are du e to different degrees of stimulation by CCK, We have therefore evalua ted the amino acid consumption test by examining the dose-response rel ation among increasing doses of cerulein and plasma amino acids compar ed with the release of pancreatic polypeptide in six healthy volunteer s and six patients with severe pancreatic insufficiency proven by a pa thological para-aminobenzoic acid test. Methods: Stepwise increasing d oses of cerulein (10-80 pmol/kg/h) were given i.v., each for 60 min wi th a secretin background (1 CU/kg/h), In the volunteer group, an addit ional experiment with infusion of placebo (saline 0.9%) was performed. Results: CCK-induced amino acid changes were small in volunteers (max imum decrease: 8.4 +/- 0.9%; mean +/- SEM), tended to be more pronounc ed in patients (maximum decrease: 13.8 +/- 2.8%; NS), and did not perm it a distinction among volunteers and patients, There was no dose-resp onse relationship between CCK and plasma amino acids in either group, In contrast, pancreatic polypeptide levels increased markedly and dose -dependently in volunteers and patients and tended to be lower in pati ents with pancreatic insufficiency, Conclusions: The decrease of plasm a amino acid levels in response to cerulein does not reflect pancreati c function and does not permit the diagnosis of pancreatic insufficien cy.