Role of cholecystokinin in the gastric motor response to a meal in horses

• Published in: American journal of veterinary research Vol. 67; no. 12; pp. 1998 - 2005
• Main Authors: Lorenzo-Figueras, M, Merritt, A.M
• Format: Journal Article
• Language: English
• Published: United States 01-12-2006
• Subjects: Animal Feed; Animals; antagonists; blood chemistry; Carbon Isotopes - analysis; cholecystokinin; Cholecystokinin - blood; Cholecystokinin - physiology; Devazepide - administration & dosage; Devazepide - pharmacology; dietary carbohydrate; Dietary Carbohydrates - administration & dosage; dietary fat; Dietary Fats - administration & dosage; feed intake; Female; gastric emptying; Gastric Emptying - drug effects; Gastric Emptying - physiology; gastrointestinal motility; Hormone Antagonists - administration & dosage; Hormone Antagonists - pharmacology; horses; Horses - physiology; Iodine Isotopes - analysis; Male; Muscle Relaxation - drug effects; protein content; Random Allocation; receptors; Receptors, Cholecystokinin - antagonists & inhibitors; Stomach - physiology; Time Factors; vagus nerve
• ISSN: 0002-9645; 1943-5681
• DOI: 10.2460/ajvr.67.12.1998

To measure plasma cholecystokinin (CCK) activity and the effect of a CCK-1 receptor antagonist on accommodation of the proximal portion of the stomach, and subsequent gastric emptying, in horses after ingestion of high-fat or high-carbohydrate meals.
6 healthy adult horses with gastric cannulas.
In the first study, horses were offered a high-fat (8% fat) or a high-carbohydrate (3% fat) pelleted meal of identical volume, caloric density, and protein content. Related plasma CCK-like activity was measured by radioimmunoassay (RIA). In a separate experiment, a horse was fed a grain meal with corn oil and phenylalanine, and plasma CCK activity was assessed by bioassay. A second study evaluated the effect of a CCK-1 receptor antagonist, devazepide (0.1 mg/kg, IV), on gastric accommodation and emptying following a meal of grain supplemented with either corn oil (12.3% fat) or an isocaloric amount of glucose (2.9% fat). Gastric tone was measured by a barostat and emptying by the (13)C-octanoic acid breath test.
No plasma CCK-like activity was detected by RIA or bioassay before or after ingestion of meals. Preprandial devazepide did not alter the gastric accommodation response but did significantly shorten the gastric half-emptying time and time to peak breath (13)CO(2) content with the glucose-enriched meal.
In horses, CCK participates in regulating the gastric motor response to a meal. Compared with other species, horses may be more responsive to carbohydrate than fat. A vagovagal reflex most likely mediates this regulation, with CCK as a paracrine intermediary at the intestinal level.