Prokinetic Effect of Indoramin, an Alpha Adrenergic Antagonist, on Gall Bladder Motility in Subjects with Gall Stone Disease

Introduction: Alpha adrenergic antagonist has been found in previous studies to have a prokinetic effect on gall bladder motility in normal human subjects. However their effects have not been fully elucidated in subjects with gallstone disease.

Aims & Methods: Our aim was to determine the effects of alpha- and beta-antagonists on gall bladder motility in human subjects with gall stone disease.

A slow release formulation of propranolol 80mg (beta antagonist), and indoramin 25mg (alpha antagonist), and placebo were administered to 10 subjects with gall stone disease on three separate days 8 hours before assessment of gall bladder volumes by ultrasonography. Gall bladder volumes were assessed in the fasting state and at 5 minute intervals for 50 minutes after a standard proprietary enteral feed (Ensure 180ml, Abbott). Differences between the placebo and post adrenergic antagonist scan volumes were tested using the Wilcoxon signed rank test, with p<0.05 taken as significant.

Results: There were no significant differences in the fasting volumes of gall bladder after receiving propranolol, indoramin and placebo (24.2±4.3ml, 22.8±4.8ml, 27.6±7.4ml, mean±SEM respectively). However when post prandial gall bladder volumes were compared, indoramin significantly enhanced post prandial gall bladder emptying compared to placebo at 25 minutes (12.4±2.2ml, and 22.7±5.6ml, mean±SEM, respectively, p<0.05). There were no significant post prandial gall bladder volume differences between propranolol and placebo.

Conclusion: Indoramin acts as a prokinetic agent enhancing post-prandial gall bladder emptying in subjects with gall stone disease.