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

This research explores the indication that the hormone cholecystokinin (CCK) has a role in controlling the movement of food in horse’s stomach after consuming high-fat or high-carbohydrate meals.

Objective of the Study

The study aimed to explore two primary components:

• Firstly, the research investigated plasma CCK activity in horses after they consume a high-fat or high-carbohydrate meal.
• Secondly, the study sought to comprehend the impact of a CCK-1 receptor antagonist (a substance that blocks CCK) on how the horse’s stomach adjusts and empties after meal intake.

Methods Used in the Research

The study used healthy adult horses with gastric cannulas. For the first investigation, researchers fed the horses a high-fat or high-carbohydrate meal with identical volume, caloric density, and protein content. They measured the related plasma CCK-like activity using radioimmunoassay (RIA).

For the assessment of plasma CCK activity, they gave a horse a grain meal with corn oil and phenylalanine, which they then measured with bioassay. In the second investigation, they looked into the effects of the CCK-1 receptor antagonist, devazepide, on the stomach’s accommodation and emptying after the horse consumed grain meal supplemented with either corn oil or an identical calorie amount of glucose. They monitored gastric tone using a barostat and measured emptying with the 13C-octanoic acid breath test.

Results and Conclusions

The results found no evidence of plasma CCK-like activity either before or after meal intake. Although administering devazepide before meals did not modify the stomach’s accommodation response, it did significantly shorten both the gastric half-emptying time and time to peak breath 13CO2 content when the horse consumed the glucose-enriched meal.

The conclusion established in the study was that in horses, CCK contributes to regulating the gastric motor response to a meal. Besides, it also suggested that horses might respond more positively to carbohydrates than fat compared to other species. The researchers proposed that this regulation most likely occurs via a vagovagal reflex, with CCK acting as a paracrine intermediary at the intestinal level.