Prokinetic effect of indoramin, an alpha-adrenergic antagonist, on human gall-bladder.
BACKGROUND
The effects of alpha- and beta-adrenergic agents on gall-bladder motility remain undefined.


OBJECTIVE
To determine the effects of alpha- and beta-antagonists on gall-bladder motility in healthy humans.


METHODS
In this single, blind, three-way crossover study, a slow-release formulation of propranolol 80 mg (beta-antagonist), indoramin 25 mg (post-synaptic alpha1-antagonist) and placebo were administered to 10 healthy volunteers on three separate days 8 h before the assessment of gall-bladder volumes by ultrasonography. Gall-bladder volumes were assessed in the fasting state and at 5-min intervals for 50 min after a standard proprietary enteral feed (Ensure 186 mL, Abbott).


RESULTS
The fasting gall-bladder volumes of subjects who received placebo or indoramin were significantly different (mean +/- S.E.M.: 16.50 +/- 2.78 mL and 13.47 +/- 2.24 mL, respectively; P < 0.001, two-way analysis of variance). The fasting gall-bladder volume after the administration of propranolol was 17.49 +/- 2.37 mL and was not significantly different from placebo (16.50 +/- 2.78 mL). When the mean post-prandial gall-bladder volumes were compared, indoramin significantly enhanced post-prandial gall-bladder emptying compared to placebo (P < 0.001). There was no significant post-prandial volume difference between placebo and propranolol.


CONCLUSIONS
Indoramin, an alpha-adrenergic antagonist, acts as a prokinetic agent, enhancing post-prandial gall-bladder emptying in healthy individuals.
Sengupta
S
S
Department of Medical and Gastroenterology, Mayo General Hospital, Castlebar, Ireland.
Cooney
R
R
Baj
M
M
Ni'Muircheartaigh
R
R
O'Donnell
L J D
LJ
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000328:Adult; D018592:Cross-Over Studies; D005215:Fasting / Q000502:physiology; D005260:Female; D016473:Gallbladder Emptying / Q000187:drug effects*; D006801:Humans; D007217:Indoramin / Q000494:pharmacology*; D008297:Male; D019518:Postprandial Period / Q000502:physiology; D011433:Propranolol / Q000494:pharmacology; D016037:Single-Blind Method
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D007217:Indoramin; D011433:Propranolol