Changes of small bowel motility and noradrenaline content of the intestinal wall in response to alpha- and beta-adrenergic blockade in dog.
In experiments on dogs, the spontaneous movements of the small bowel were in all cases enhanced by the alpha 2-blocker phentolamine, while they were not influenced, or were slightly decreased, by the beta 1-blocker practolol. Neither drug caused a change in the noradrenaline content of the intestinal wall. In the same animals, the joint administration of phentolamine and practolol led to a considerable increased small bowel motility, and to a significant decrease in the noradrenaline level of the intestinal wall. The results are in agreement with experimental data indicating that presynaptic alpha-receptors play a primary role in the sympathetic regulation of small bowel motility.
D000818:Animals; D004285:Dogs; D004347:Drug Interactions; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D007422:Intestines / Q000032:analysis*; D008297:Male; D009638:Norepinephrine / Q000032:analysis*; D011217:Practolol / Q000008:administration & dosage / Q000494:pharmacology*; D011433:Propranolol / Q000008:administration & dosage / Q000494:pharmacology*
D011433:Propranolol; D011217:Practolol; D009638:Norepinephrine