The Importance of Refractoriness in Ovine Antral Digestive and Interdigestive Motility

Authors : Krzysztof Waldemar ROMA´NSKI

Pages : 347-352

View : 18 | Download : 11

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The aim of this work was to find possible differences between the effects of anticholinergic drug administration during the duodenal phase 1 or phase 2a of migrating myoelectric complex on antral spike burst amplitude in fasted and non-fasted sheep. Eight adult rams possessing bipolar electrodes in the antrum and small intestine were used in the study. Feeding increased significantly the spike burst amplitude range from 60-110 to 80-160 µV. The effects of hexamethonium insert ignore into journalissuearticles values(2 mg/kg);, atropine insert ignore into journalissuearticles values(0.1 mg/kg); and pirenzepine insert ignore into journalissuearticles values(0.5 mg/kg); given i.v. during phase 1 of the migrating myoelectric complex insert ignore into journalissuearticles values(expressed as per cent of control); in non-fasted sheep were 68 ± 18, P < 0.05, 69 ± 20, P < 0.05, 45 ± 18, P < 0.01, respectively. The effects of the same doses of these drugs given during phase 2a of the migrating myoelectric complex in non-fasted sheep were 54 ± 13, P < 0.01, 41 ± 12, P < 0.0001, 33 ± 11, P < 0.0001, respectively. In non-fasted animals, the anticholinergic drugs exerted a more pronounced effect than in fasted animals. These effects were partially dose-dependent. The effects of drug combinations were not additive. It is concluded that the effects of anticholinergic substances given during phase 1 or 2a of migrating myoelectric complex and under various feeding conditions on ovine antral spike burst amplitude can vary, partially due to the intensity of the refractory period.
Keywords : Sheep, abomasal antrum, myoelectric activity, feeding, anticholinergic drugs