Inhibitory effect of intraduodenal administration of somatostatin analogue SDZ CO 611 on rat pancreatic exocrine secretion.

The inhibitory effect of the intraduodenal administration of a new somatostatin analogue, SDZ CO 611 (SDZ), on pancreatic secretion was evaluated in the rat. The exocrine pancreas was stimulated by either intravenous infusion of both secretion (0.06 CU/kg/h) and cholecystokinin octapeptide (CCK-8) (0.03 microgram/kg/h) or intraduodenal infusion of oleic acid (0.25 mmol/h) or casein (200 mg/h). Intraduodenal administration of SDZ in three different doses, 0.5, 1.0, and 2.0 mg/kg/h, resulted in dose-related inhibition of pancreatic secretion, including juice volume, bicarbonate, and amylase, stimulated by exogenous secretin and CCK. Intraduodenal oleic acid- and casein-induced increases in pancreatic secretion in terms of juice volume, bicarbonate, and amylase were also significantly suppressed by intraduodenal administration of SDZ in a dose of 2.0 mg/kg/h. Moreover, SDZ (2.0 mg/kg/h) significantly inhibited basal pancreatic secretion. It is concluded that the intraduodenal administration of SDZ inhibits pancreatic secretion stimulated by exogenous secretin and CCK-8 in physiological doses and by intestinal nutrients in the rat.