ABSTRACT
Information obtained from studies on muscle resected from patients with inflammatory bowel disease is crucial to our understanding of the mechanisms underlying altered motility in the inflamed bowel. The motility apparatus of the gut includes smooth muscle and extrinsic and intrinsic nerves. An inflammatory process in the gut may modify motility by quantitatively or qualitatively altering these structures. The nematodes Nippostronqylus brasiliensis and Trichinella spiralis induce inflammatory changes in the mucosa and submucosa of rat jejunum that are time-dependent and reversible. The increased contractile responsiveness of longitudinal smooth muscle from the N.brasiliensis infected rat was prevented by treating the animals with corticosteroid. Different effects observed on circular and longitudinal muscle emphasizes that correlations between in vivo and in vitro studies should take into account studies on both circular and longitudinal smooth muscle. Abnormal patterns of electrical activity in response to carbachol were observed only in circular muscle, longitudinal muscle responded in a manner similar to control.
