Effect of exogenous somatostatin infusion on gastrointestinal blood flow and hormones in the conscious dog.

The purpose of this study was to investigate the effects of intravenous somatostatin infusion on gastrointestinal blood flow and hormone release in conscious dogs. Gastric, duodenal, jejunal, and pancreatic blood flows, quantitated using radioactive microspheres, were significantly decreased during somatostatin infusion (200 and 500 ng/kg min), resulting in an overall 30% reduction in summed portal blood flow. Fasting blood levels of glucose fell an average of 10 mg/dl. Immunoreactive insulin, gastrin, glucagon, and pancreatic polypeptide were all profoundly suppressed by somatostatin infusion. Our studies provide one possible explanation for somatostatin's apparent effectiveness in the control of upper gastrointestinal hemorrhage.