Stomach

In anatomy, the stomach (in ancient Greek στόμαχος) is an organ in the alimentary canal used to digest food. Generally, the stomach's primary function is not the absorption of nutrients from digested food; this task is usually performed by the intestine.

Control of secretion and motility

The movement and the flow of chemicals into the stomach are controlled by both the autonomic nervous system and by various digestive system hormones.

Related Topics:
Autonomic nervous system - Hormone

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The hormone gastrin causes an increase in the secretion of HCl, pepsinogen and intrinsic factor from parietal cells in the stomach. It also causes increased motility in the stomach. Gastrin is released by G cells in the stomach to distenstion of the antrum, and digestive products. It is inhibited by a pH normally less than 4 (high acid), as well as the hormone somatostatin.

Related Topics:
Gastrin - Intrinsic factor - Parietal cell - PH - Somatostatin

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Cholecystokinin (CCK) has most effect on the gall bladder, but it also decreases gastric emptying. Similarly secretin, produced in the small intestine, has most effects on the pancreas, but will also diminish acid secretion in the stomach.

Related Topics:
Cholecystokinin - Gall bladder - Secretin

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Gastric inhibitory peptide (GIP) and enteroglucagon decrease both gastric acid and motility.

Related Topics:
Gastric inhibitory peptide - Enteroglucagon

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Other than gastrin, these hormones all act to turn off the stomach action. This is in response to food products in the intestines, which have not yet been absorbed. The stomach only needs to push food into the small intestine when the intestine isn't busy. While the intestine is full and still digesting food, the stomach acts as a storage hopper for food.

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This pattern is also present in the nervous control of the stomach.

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