The Stomach: Introduction and Index

Foodstuffs entering the stomach have been, to at least some extent, crushed and reduced in size by mastication, and impregnanted with saliva. The stomach provides four basic functions that assist in the early stages of digestion and prepare the ingesta for further processing in the small intestine:

1. It serves as a short-term storage reservoir, allowing a rather large meal to be consumed quickly and dealt with over an extended period of time.
2. It is in the stomach that substantial enzymatic digestion is initiated, particularly of proteins.
3. Vigorous contractions of gastric smooth muscle mix and grind foodstuffs with gastric secretions, resulting in liquefaction of food, a prerequisite for delivery of the ingesta to the small intestine.
4. As food is liquefied in the stomach, it is slowly released into the small intestine for further processing.

Core gastric physiology is presented as the following topics:

• Gross and microscopic anatomy of the stomach
• Gastric motility - filling and emptying
• Gastric secretions
• Absorption in the stomach
• One meal in the life of the stomach

Advanced and supplemental topics related to gastric physiology:

• Secretory Processes
• The Parietal Cell and the Mechanism of Acid Secretion
• Drug Therapy for Suppressing Secretion of Gastric Acid
• Pepsin and Pepsinogens
• Rennin and the Coagulation of Milk
• Intrinsic Factor
• Enterochromaffin-Like (ECL) Cells
• Gastric Motility
• Control of Gastric Emptying
• The Migrating Motor Complex
• Gastrointestinal Transit: How Long Does It Take?

Pathophysiology and diseases affecting the stomach:

• Physiology of Vomiting
• The Gastrointestinal Barrier