Effect of physical training on changes in plasma gastrointestinal hormones due to exercise in man

In order to investigate the effect of physical exercise training on gastrointestinal function, changes in plasma gastrin and cholecystokinin (CCK) due to an acute exercise were examined before and after the training in six untrained healthy men. After overnight fasting, the subjects ran on a treadmill at 60% of VO(2max) for 30 minutes. Blood was sampled immediately before the exercise (rest), 10 and 20 minutes during the exercise, and immediately, 10, 30, and 90 minutes after the exercise. Plasma gastrin, CCK, glycerol, lactate, insulin, and glucagon were measured. With plasma gastrin, the level at rest was significantly lower after the training than before the training, and the change during the exercise which showed a gradual increase was identical between before and after the training. Peak value of plasma gastrin observed at 10 minutes after the exercise in both conditions showed no significant difference, showing the increase from the rest was significantly higher after the training than before the training. Changes in plasma CCK, glycerol, lactate, insulin, and glucagon due to the exercise were not significantly different between before and after the training. These results suggests that physical exercise training with moderate intensity might cause adaptive change(s) in gastrin action on the target cell such as an increase in sensitivity of gastrin receptors.