title: Use of gut cyclic motor activity to evaluate a stimulant (narcotic) and inhibitor (anticholinergic) of gastrointestinal-tract activity in the unanesthetized dog.
abstract: The use of gut cyclic motor activity to evaluate both a stimulant and inhibitor of gastrointestinal contractile activity in the unanesthetized dog is described. In the interdigestive (fasted) state, there is a cyclic alternation of intense periods of contractions (burst) with quiescent periods (basal). Codeine phosphate, a narcotic agent, caused a dose-dependent increase in the number and duration of circular muscle contractions when administered in the basal phase. Hyoscine N-butyl-bromide, an anticholinergic drug, caused a dose-dependent reduction in both amplitude and frequency of burst-phase contractions. When a combination of codeine phosphate and hyoscine N-butylbromide was administered simultaneously in the basal or burst phase, the hyoscine N-butylbromide prevailed and had the dominant effect. This is a useful in vivo model to evaluate the effects of drugs on the gastrointestinal tract.
mesh_terms: D000818:Animals; D003061:Codeine / Q000031:analogs & derivatives / Q000494:pharmacology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D009119:Muscle Contraction / Q000187:drug effects; D009294:Narcotics / Q000494:pharmacology*; D010276:Parasympatholytics / Q000494:pharmacology*; D012601:Scopolamine / Q000494:pharmacology
chemical_list: D009294:Narcotics; D010276:Parasympatholytics; D012601:Scopolamine; D003061:Codeine