Feedback regulation of pancreatic enzyme secretion. Suppression of cholecystokinin release by trypsin

C Owyang, D S Louie, D Tatum, C Owyang, D S Louie, D Tatum

Abstract

Feedback regulation of pancreatic enzyme secretion occurs in rats. Whether such a system exists in man remains unsettled and the responsible mechanism is unknown. To investigate this question gastrointestinal intubation and perfusion were performed in 12 healthy subjects. Intraduodenal perfusion of trypsin-inhibited phenylalanine-, oleic acid-, and meal-stimulated chymotrypsin and lipase outputs in a dose-related manner. The minimal concentration of bovine trypsin needed to inhibit pancreatic enzyme secretion was 0.5 g/liter. 1 g/liter caused a maximal suppression of 35 +/- 4% of the phenylalanine-stimulated chymotrypsin release. This inhibitory effect was protease-specific. Intraduodenal perfusion of phenylalanine and oleic acid increased plasma cholecystokinin (CCK) from a basal level of 0.9 +/- 0.06 to 5.3 +/- 0.9 pM and 7.2 +/- 1.3 pM, respectively. Addition of bovine trypsin to the perfusates significantly reduced the plasma CCK level to basal values. This inhibitory effect of trypsin on CCK release was dose dependent and specific to proteases. Therefore, the present studies indicate that feedback regulation of pancreatic enzyme secretion is operative in man and it is mediated by release of CCK.

References

    1. J Clin Invest. 1985 Apr;75(4):1144-52
    1. Proc Soc Exp Biol Med. 1972 May;140(1):6-12
    1. Gastroenterology. 1974 Jan;66(1):22-7
    1. Am J Physiol. 1986 Feb;250(2 Pt 1):G252-9
    1. Am J Physiol. 1969 Sep;217(3):646-51
    1. J Endocrinol. 1978 Oct;79(1):17-27
    1. Am J Physiol. 1978 Dec;235(6):E743-9
    1. Gastroenterology. 1982 Jul;83(1 Pt 1):55-62
    1. Clin Chim Acta. 1980 Jan 1;100(1):7-11
    1. Dig Dis Sci. 1983 Feb;28(2):97-102
    1. J Physiol. 1943 Jun 30;102(1):115-25
    1. Gastroenterology. 1968 Aug;55(2):157-64
    1. Am J Physiol. 1962 Feb;202:285-8
    1. Digestion. 1977;15(6):540-55
    1. Gastroenterology. 1984 Jul;87(1):44-52
    1. Scand J Gastroenterol. 1976;11(1):11-5
    1. J Clin Invest. 1985 May;75(5):1471-6
    1. Gastroenterology. 1982 Mar;82(3):406-12
    1. J Lab Clin Med. 1980 JAN;95(1):13-8
    1. Gastroenterology. 1984 Sep;87(3):542-9
    1. Digestion. 1977;15(4):303-8
    1. Gastroenterology. 1970 Mar;58(3):321-8
    1. Gastroenterology. 1982 Mar;82(3):438-44
    1. Dig Dis Sci. 1979 Feb;24(2):101-10

Source: PubMed

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