Cholecystokinin mediates feedback regulation of pancreatic enzyme secretion in rats

1986 ◽  
Vol 250 (2) ◽  
pp. G252-G259 ◽  
Author(s):  
D. S. Louie ◽  
D. May ◽  
P. Miller ◽  
C. Owyang

Previous studies have shown that trypsin and chymotrypsin in the duodenum exert a negative-feedback regulation on pancreatic enzyme secretion in the rat. The mechanism responsible for this physiological phenomenon is unknown. By use of a specific and sensitive bioassay based on amylase release from isolated pancreatic acini, the role of cholecystokinin in the negative-feedback regulation of exocrine pancreatic secretion was examined. Rats were prepared with duodenal cannulas and pancreaticobiliary cannulas. Diversion of pancreaticobiliary juice resulted in a threefold increase in pancreatic protein output and an increase of plasma cholecystokinin from a basal level of 0.5 +/- 0.08 pM cholecystokinin octapeptide (CCK-8) to 16 +/- 4 pM CCK-8. Perfusion of trypsin (2 mg/h) or pancreaticobiliary juice returned pancreatic protein output to basal levels and plasma cholecystokinin to 2.1 +/- 1.2 and 0.33 +/- 0.1 pM, respectively. The inhibitory effect of trypsin on cholecystokinin release was enzyme and site specific, since inhibition of cholecystokinin release was not observed with perfusion of amylase into the duodenum or with trypsin into the ileum. Intravenous infusion of proglumide abolished the increase in pancreatic secretion following diversion of pancreaticobiliary juice. Intraduodenal perfusion of lidocaine, infusion of tetrodotoxin into the superior mesenteric artery, or intravenous infusion of atropine inhibited the rise in plasma cholecystokinin seen with diversion of pancreaticobiliary juice. These studies suggest that feedback regulation of pancreatic enzyme secretion in the rat is mediated by release of cholecystokinin. Furthermore, the feedback mechanism is neurally mediated, involving a cholinergic pathway.

2020 ◽  
Vol 1 (30) ◽  
pp. 30-36
Author(s):  
E. A. Krylova ◽  
D. V. Aleinik

The article presents the results of a study of the effectiveness of the use of an inhibitor of pancreatic enzyme secretion of octreotide (Octrade) for the prevention of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). It was shown that the administration of Octrade at a dose of 0.3 mg in 500 ml of 0.9 % NaCl by continuous intravenous infusion for 7 hours and then 0.1 mg of Octrade subcutaneously at 6 and 12 hours after the end of intravenous infusion significantly reduced the frequency of pancreatitis (4.0 % and 22.2 %; p < 0.05) and hyperamylasemia (8.0 % and 25.9 %; p < 0.05) after ERCP. It is concluded that Octrade is effective in preventing the development of pancreatitis and hyperamilasemia after ERCP.


1993 ◽  
Vol 265 (2) ◽  
pp. G251-G257 ◽  
Author(s):  
Y. Li ◽  
C. Owyang

The mechanisms and site of action of somatostatin-induced inhibition of pancreatic enzyme secretion were investigated using different stimulants of pancreatic secretion acting on different sites in anesthetized rats. Administration of graded doses of somatostatin-14 resulted in a dose-related inhibition of pancreatic protein secretion evoked by 2-deoxy-D-glucose, a central vagal stimulant that acts by stimulating the dorsal vagal nuclei. The lowest effective dose of somatostatin-14 was 1.0 microgram.kg-1 x h-1; maximal effective dose was 25 micrograms.kg-1 x h-1, which resulted in complete inhibition of protein output. Similarly, somatostatin-14 at a dose of 25 micrograms.kg-1 x h-1 also completely inhibited pancreatic protein secretion in response to a physiological concentration of cholecystokinin octapeptide (CCK-8), which acts via a vagal afferent pathway. In contrast, pancreatic protein outputs evoked by bethanechol, which directly stimulates pancreatic muscarinic receptors, or electrical stimulation of the vagal trunk, which activates the vagal efferent pathway, were unaffected by somatostatin-14. In separate studies, we demonstrated that perivagal treatment with the sensory neurotoxin capsaicin impaired pancreatic responses to CCK-8 but had no effect on the inhibitory action of somatostatin-14 on pancreatic secretion evoked by 2-deoxy-D-glucose, ruling out an effect of somatostatin on the vagal afferent pathway. Similarly we also demonstrated that perineural capsaicin treatment of the celiac-superior mesenteric ganglia did not affect the inhibitory action of somatostatin. These findings indicate that somatostatin inhibits 2-deoxy-D-glucose- and CCK-8-evoked pancreatic enzyme secretion via a vagal pathway.(ABSTRACT TRUNCATED AT 250 WORDS)


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