Cholescintigraphic study of effect of somatostatin analog, octreotide, on bile secretion and gallbladder emptying in normal subjects.

The objective of the study was to investigate the effects of a single intravenous injection of the somatostatin analog octreotide on hepatic bile secretion and gallbladder emptying with a quantitative scintigraphic technique. Twelve healthy volunteers received, in a double-blind randomized fashion, either octreotide, 100 micrograms intravenously, or placebo. Ten minutes later, [99mTc]PBIDA was administered intravenously (50 microCi/kg) (time = 0) followed, 60 min later, by the ingestion of a standardized fatty meal. In the liver area, the relative decrease per minute of tracer activity from the time of maximal activity to 60 min was significantly lower in the octreotide group (P = 0.02). In the gallbladder area, after the fatty meal, the ratio of tracer activity at 60 and 90 min (A90/A60) was significantly (P = 0.01) higher in the octreotide group. Our study demonstrates that octreotide slows down liver release of the radiopharmaceutical, probably reflecting decreased bile secretion, and inhibits postprandial gallbladder contraction.