The stomach wall is lined with millions of gastric pits which release gastric juice into the stomach lumen
- Gastric juice is an acidic solution that functions to break down food into a creamy paste called chyme
The gastric pits are lined by a number of different cell types which contribute to the overall function of the stomach:
- Goblet cells – secrete mucus to form a protective layer around the stomach lining
- Parietal cells – secrete hydrochloric acid which is responsible for creating a low pH environment in the stomach
- G cells – secrete gastrin (stimulates release of stomach acids to increase stomach acidity)
- D cells – secrete somatostatin (inhibits release of stomach acids to reduce stomach acidity)
- Chief cells – secrete pepsinogen (inactive protease precursor which is activated by acidity to form active pepsin)
Structure of a Typical Gastric Pit
