Erythromycin stimulates gallbladder emptying and motilin release by atropine-sensitive pathways

Abstract

The effect of administering different doses of erythromycin on gallbladder emptying and plasma concentrations of immunoreactive motilin was investigated in healthy volunteers. Erythromycin was infused for 30 min at four different doses: 20, 50, 100, and 1000 mg/hr. Gallbladder volume was determined by ultrasound scanning every 10 min for 60 min. All doses, except 20 mg/hr, provoked a significant reduction in gallbladder volume (PPP<0.001). Our results suggest that atropine acts by inhibiting an erythromycin-activated cholinergic neural mechanism. Somatostatin could exert its inhibitory effect by blocking the release of acetylcholine from neural terminations.