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Updated: Oct 26, 2026

Gastrointestinal Motility Monitor (GIMM)
Published on: December 1, 2010
[Adrenergic mechanism of the stimulation of the small intestine motor activity]
1Institute of Experimental Medicine of the Russian Acad. Med. Sci., St. Petersburg, Russia.
Abstract:
Myoelectrical activity of the duodenum and ileum was recorded in rabbits with implanted electrode. Acute haemorrhage caused either elevation or reduction of the firing rate, the responses being abolished with a combined blockade of alpha- and beta-adrenoreceptors. Beta-adrenoreceptors agonist isoproterenol resulted in a biphasic (decrease-increase) change of the myoelectrical activity which could be abolished with blockade of beta-adrenoreceptors. The character of the small intestine motor responses to acute haemorrhage and isoproterenol infusion depended on the initial level of the intestinal contractile activity. The findings suggest that catecholamines induce a small intestinal motor effect via stimulation of both inhibitory adrenoreceptors and excitatory presynaptic adrenoreceptors.
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