A METHOD FOR SIMULTANEOUS RECORDING AND ASSESSMENT OF GUT CONTRACTIONS AND RELAXATIONS IN-VIVO

The normal gut exhibits both contractions and relaxation from a restin g tonus. Pathological and pharmacological information may be gleaned f rom separate measurement of these activities. Methods for recording an d analyzing gut contractions have been presented before. We present an extension to the methods, utilising simple foil strain gauges tested here in male Sprague-Dawley mts. Coupled with a computer-based data ac quisition and analysis system, we could assess the relaxation and cont raction waves recorded simultaneously and from different gut regions i n vivo. In contrast with the antrum, where spontaneous motor activity consisted of low frequency relaxations and random contractions, sponta neous duodenal motility was patterned into periodic groups of intense activity interposed by periods of low amplitude, low frequency contrac tions and relaxations. This grouped activity was propagatory, reminisc ent of migrating myoelectrical complexes. When challenged with the ulc erogen cysteamine-HCl (56 mg/100 g s.c.), only duodenal motor activity was affected. Moreover, this treatment had differential effects in th e duodenum. Patterned motility was no longer distinguishable, and cont raction frequency and amplitude were increased while relaxation amplit ude was decreased. This method affords a particularly sensitive and mo re precise assessment of both contractile and relaxant motor activity in vivo, before and after drug treatment.