PERSISTENT INTESTINAL NEUROMUSCULAR DYSFUNCTION AFTER ACUTE NEMATODE INFECTION IN MICE

Background & Aims: Although most acute enteric infections in humans re solve, some herald the onset of chronic symptomatology and persistent gastrointestinal dysfunction - so-called postinfectious irritable bowe l syndrome, This entity is poorly understood, and there are no animal models for testing hypotheses. The aim of this study was to investigat e changes in intestinal neuromuscular function during and after recove ry from acute intestinal inflammation due to primary Trichinella spira lis infections in NIH Swiss mice, Methods: Morphometric scores and mye loperoxidase activity were used to monitor mucosal inflammation, Neuro muscular function was assessed in vitro by pharmacological or electric al stimulation of longitudinal muscle. Results: Acute inflammation res ulted in an similar to 50% reduction of villus height, an similar to 5 0% increase in crypt depth, and a threefold increase in myeloperoxidas e activity, Carbachol-and KCI-induced contractions of longitudinal mus cle were also increased threefold, whereas contraction induced by elec trical field stimulation of intramural nerves was decreased by 60%. Mu cosal morphology, and myeloperoxidase activity rap idly returned to co ntrol values, but the increased muscle contractility and the decreased excitatory neurotransmission persisted as long as 42 and 28 days afte r infection, respectively. Conclusions: These findings show that trans ient mucosal inflammation alters enteric neuromuscular function; this alteration persists after recovery from the infection and mucosal rest itution.