TNBS-induced inflammation impairs organized myoelectric activity in the rat small intestine

Abstract

Background It has been known for several years that nematode-induced enteric inflammation impairs myoelectric and contractile activity, More recently, several studies showed that trinitrobenzene sulfonic acid (TNBS) induced inflammation alters in vitro muscle strip contractility. To our knowledge, the effect of TNBS-induced inflammation on small intestinal motility has not been studied in viva in the rat. Aim: To characterize the changes in small intestinal myoelectric activity caused by TNBS-induced inflammation. Methods: 4 bipolar electrodes were implanted at regular intervals on the antimesenterial side of the proximal jejunum of 13 male Wistar rats (250-350 g). During surgery, we administered intraluminally 30 mg TNBS in 0.25 ml ethanol 40% (n=5), 0.25 ml ethanol 40% (n=4) or 0.25 ml water (n=4). One week later, fasting myoelectric activity was recorded during at least 1 hour. The tracings were analyzed semiautomatically and several parameters concerning phase 3 (P3) and the migrating myoelectric complex (MMC) were examined. Results (mean 4SEM) were compared using ANOVA and Chi-square test. Results: Anaiysis of parameters at a single electrode site