Evaluation of somatostatin inhibitory effect on pancreatic exocrine function using secretin-enhanced dynamic magnetic resonance cholangiopancreatography: a crossover, randomized, double blind, placebo-controlled study.

OBJECTIVES

Somatostatin inhibitory effect on the exocrine pancreas has been demonstrated by clinical and experimental studies performed with invasive investigative methods. The aim of this study was to quantify the inhibitory effect of low doses of somatostatin (62.5, 125, and 250 microg) on secretin-stimulated pancreatic exocrine secretions using magnetic resonance cholangiopancreatography (MRCP).

METHODS

Ten healthy volunteers underwent 4 MRCP at a 1-week interval. At each MRCP, 1 of the 3 doses of Somatostatin or the placebo was given by the intravenous route for a period of 40 minutes. After 20 minutes from the beginning of drug infusion, secretin was injected (0.3 CU/kg). MRCP was performed before and every 30 to 45 seconds for 15 minutes after secretin administration. Pancreatic exocrine secretions were quantified by the measurements of pancreatic flow output and total excreted volume, derived from a linear regression between MRCP calculated volumes and time.

RESULTS

For the 3 doses of somatostatin, pancreatic flow output was significantly reduced compared to placebo (P < 0.05). Total excreted volume was significantly reduced only for the doses of 62.5 and 250 microg. No statistical significant differences were observed among the 3 doses.

CONCLUSIONS

Low doses of somatostatin inhibit pancreatic exocrine secretions as demonstrated noninvasively with MRCP.