[Adrenergic mechanism of the stimulation of the small intestine motor activity].
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.
Ovsiannikov
V I
VI
Institute of Experimental Medicine of the Russian Acad. Med. Sci., St. Petersburg, Russia.
D000200:Action Potentials / Q000187:drug effects; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D004386:Duodenum / Q000187:drug effects / Q000502:physiology*; D005769:Gastrointestinal Motility / Q000187:drug effects / Q000502:physiology*; D006470:Hemorrhage / Q000503:physiopathology; D007082:Ileum / Q000187:drug effects / Q000502:physiology*; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D011817:Rabbits
D000317:Adrenergic alpha-Antagonists; D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D018727:Muscarinic Antagonists; D007545:Isoproterenol
Adrenergicheskiĭ mekhanizm stimuliatsii motornoĭ aktivnosti tonkoĭ kishki.