Stimulation of gastrointestinal motility by loperamide in dogs.
The effects of loperamide on gastrointestinal motility were investigated in conscious fasted dogs chronically fitted with strain-gauge transducers on the antrum, the jejunum, and the colon. Oral administration of loperamide (0.1 mg/kg) induced, after a delay of 20-30 min, a long-lasting (8-12 hr) stimulation of gastrointestinal motility associated with a disorganization of the cyclic activity at the three levels investigated. These effects were reproduced by a subcutaneous administration at the same dose and were antagonized by previous intravenous administration of naloxone or a quaternary opiate antagonist. Intracolonic administration (0.1 mg/kg) stimulated, after a delay of 20-30 min, colonic motility only. Intracerebroventricular loperamide (1 microgram/kg) induced a long-lasting (15-20 hr) inhibition of the gastric motility and a short (2-hr) disorganization of the jejunal motor profile. These data show that oral loperamide stimulates gastrointestinal motility in dogs and involves peripheral opiate receptors.
D000284:Administration, Oral; D000818:Animals; D003106:Colon / Q000502:physiology; D004285:Dogs; D005769:Gastrointestinal Motility / Q000187:drug effects*; D007276:Injections, Intraventricular; D007279:Injections, Subcutaneous; D007583:Jejunum / Q000502:physiology; D008139:Loperamide / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects; D009270:Naloxone / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology*; D011706:Pyloric Antrum / Q000502:physiology
D010880:Piperidines; D009270:Naloxone; D008139:Loperamide