THE EFFECT OF OCTREOTIDE ACETATE ON MEAL-STIMULATED EXOCRINE SECRETION IN CANINE PANCREATIC AUTOGRAFTS

Abstract

Octreotide acetate (Sandostatin), a long-acting somatostatin analogue, has been demonstrated to have an inhibitory effect on exocrine secretion in the neurally intact pancreas. This study was designed to evaluate the effect of this agent on exocrine secretion in the denervated canine pancreas, utilizing animals with pancreatic autografts and functioning pancreaticocystostomies. The rates of secretion of urinary (autograft) amylase (units/min) and bicarbonate (mM/min), over a five-hr interval, were determined in the basal state (group A, n = 10), after a bolus injection of 400 micrograms of Sandostatin (group B, n = 5), after a standard meal (group C, n = 5), or a meal preceded by 400 micrograms of Sandostatin (group D, n = 5). Basal secretion of amylase was decreased for 4 hr following Sandostatin, although this decrease was not significant. Conversely, basal bicarbonate secretion was not inhibited by Sandostatin. When compared with group C (22.4 +/- 3.2), a significant inhibition of meal-stimulated amylase release was demonstrated in group D (5.4 +/- 0.21, P = 0.0006) during the first hour after Sandostatin was given. This inhibition remained significant at 2 hr (group C = 38.5 +/- 5.2 versus group D = 9.4 +/- 0.8; P = 0.0006) and 3 hr (group C = 38.6 +/- 6.3 versus group D = 17.5 +/- 0.9; P = 0.0108) after Sandostatin was given. In addition, meal-stimulated bicarbonate secretion was significantly inhibited for 2 hr following Sandostatin (group C = 0.19 +/- 0.03 versus group D = 0.07 +/- 0.02, P = 0.0096; and group C = 0.23 +/- 0.03 versus group D = 0.10 +/- 0.01, P = 0.0018, respectively). These studies demonstrate that Sandostatin has a profound inhibitory effect on meal-stimulated enzyme and bicarbonate release in a denervated canine autograft model. Although the site of action of this agent remains to be defined, Sandostatin may have therapeutic potential in clinical pancreas transplantation.