Effect of erythromycin lactobionate on myoelectric activity of ileum, cecum, and right ventral colon, and cecal emptying of radiolabeled markers in clinically normal ponies
Lester, G.D.; Merritt, A.M.; Neuwirth, L.; Vetro-Widenhouse, T.; Steible, C.; Rice, B.
American Journal of Veterinary Research 59(3): 328-334
1998
ISSN/ISBN: 0002-9645 PMID: 9522953 Document Number: 490927
After a 12-hour non-feeding period, 370 MBq of technetium 99m-labelled sulfur colloid in egg albumen and 37 MBq of indium 111-labelled diethyltriaminepentaacetic acid in 60 ml of water were administered directly into the caecal apex. The following drug concentrations were tested: erythromycin lactobionate (ERY), 0.01, 0.10, 1.0, and 10.0 mg/kg of body weight; ERY, 0.10 mg/kg bolus; and saline (0.9% NaCl) solution, 10 ml. All treatments, with the exception of the 0.10-mg/kg bolus and saline solution, were infusions administered i.v. during a 60-minute period in a randomized complete block design. Each treatment was administered 2 times per pony. Dual-phase scintigraphic images were obtained, and the best-fit function was determined for each study, using data from the right side. Myoelectric data were collected before and after each treatment and analysed for spike burst rate, relative activity, and burst duration. The time to 50% emptying (t50) after ERY administration was dose dependent, and all treatments, with the exception of the 0.01-mg/kg infusion, resulted in a significantly shorter t50 than that observed after saline administration (230.2+or-17.12 min). The shortest t50 was observed after the 1.0 mg/kg dosage of ERY (76.9+or-22.0 min). Although not significantly different, the t50 was shorter (108.6+or-25.9 min) after a bolus dose of 0.10 mg/kg of ERY than after infusion at the same dosage (131.1+or-18.7 min). It is suggested that ERY may be a useful prokinetic for prevention or treatment of caecal motility dysfunction.