Gastric Factors That Promote Emptying Effect of Gastric Food Volume on Rate of Emptying. Increased food volume in the stomach promotes increased emptying from the
stomach. But this increased emptying does not occur for the reasons that one would expect
Effect of the Hormone Gastrin on Stomach Emptying. In Chapter 64, we discuss how stomach wall stretch and the presence of certain types
of foods in the stomach—particularly digestive products of meat—elicit release of the hormone gastrin from the antral mucosa.
Inhibitory Effect of Enterogastric Nervous Reflexes from the Duodenum. When food enters the duodenum, multiple nervous reflexes are initiated
from the duodenal wall.
Hormonal Feedback from the Duodenum Inhibits Gastric Emptying — Role of Fats and the Hormone Cholecystokinin. Not only do nervous reflexes from the duodenum to the
stomach inhibit stomach emptying, but hormones released from the upper intestine do so as well. The
stimulus for releasing these inhibitory hormones is mainly fats entering the duodenum, although other
types of foods can increase the hormones to a lesser degree.
Other possible inhibitors of stomach emptying are the hormones secretin and gastric inhibitory peptide (GIP), also called glucose-dependent insulinotropic peptide. Secretin is released mainly from
the duodenal mucosa in response to gastric acid passed from the stomach through the pylorus. GIP has
a general but weak effect of decreasing gastrointestinal motility. In summary, hormones, especially
CCK, can inhibit gastric emptying when excess quantities of chyme, especially acidic or fatty chyme,
enter the duodenum f om the stomach.
