Effect of somatostatin on pancreatic enzyme secretion.

The effect of somatostatin (SS) on the pancreatic enzyme secretion was studied in a perfusion system using dispersed pancreatic rat acini in vitro. In addition the effect of SS on pancreatic secretion in vivo was also studied in conscious rats for comparison. In an in vitro study, 6 x 10(-7) M SS-14 caused no significant change in amylase release when added 20 min before stimulation by 10(-5) M carbamylcholine (Cch), 10(-6) M A23187, 5 x 10(-7) M secretin and 2 mM dibutyryl cyclic AMP. The addition of 6 x 10(-7) M SS-28 also caused no significant change in amylase release stimulated by 10(-5) M Cch. High performance liquid chromatographic examination indicated that no degradation of either SS-14 or SS-28 occurred after reaction with dispersed acini. In an in vivo study SS-14 caused marked inhibition of basal pancreatic secretion and stimulated pancreatic secretion by bile-pancreatic juice diversion. These results indicate that SS has no direct inhibitory action on rat pancreatic secretion, and that SS may inhibit the pancreatic secretion by indirect mechanisms.