EFFECT OF ERYTHROMYCIN ON GALLBLADDER EMPTYING IN PATIENTS WITH ANTRECTOMY OR TRUNCAL VAGOTOMY

Objectives: Erythromycin, a motilin-like agent, stimulates gallbladder contraction in healthy control subjects. Because the action of erythr omycin is cholinergic dependent and possibly related to premature phas e III migrating motor complex activity in the antrum, we investigated the effect of erythromycin on gallbladder volume in six patients with truncal vagotomy without gastric resection and 14 patients with antrec tomy (6 with Billroth I anastomosis, 8 with Billroth II anastomosis), and we compared the results obtained with those in eight healthy contr ols. In addition, the effect of meal ingestion on gallbladder volume w as studied. Methods: Gallbladder volumes, measured with ultrasonograph y, were determined every 15 min for 180 min after erythromycin infusio n (3 mg/kg i.v.), as well as 30 and 60 min after meal ingestion. Resul ts: Basal gallbladder volumes were not significantly different among t he four groups. Erythromycin induced a significant (p < 0.01-0.05) gal lbladder contraction of maximal 46 +/- 6% in the controls, 49 +/- 9% i n the patients with truncal vagotomy, and 38 +/- 7% in the patients wi th antrectomy and Billroth I anastomosis. In the patients with antrect omy and Billroth II anastomosis, no significant reduction in gallbladd er volume after erythromycin was observed. Meal-induced gallbladder co ntraction was normal in all patients, including those with Billroth II anastomosis. Conclusions: These results indicate that neither the lon g vagus nerve nor the antrum is essential for erythromycin-induced eff ects on the gallbladder. Because no significant reduction in gallbladd er volume in response to erythromycin was observed in the patients wit h antrectomy and Billroth II anastomosis, we suggest that duodenojejun al anatomical integrity is essential for erythromycin-induced gallblad der contraction.