A peptic cell, also known as a gastric chief cell or zymogenic cell, is a specialized cell located in the stomach's gastric glands. Its primary function is the production and secretion of pepsinogen and chymosin.
Pepsinogen and its Role in Digestion
Pepsinogen is a zymogen, an inactive precursor to the digestive enzyme pepsin. When pepsinogen comes into contact with the hydrochloric acid (HCl) produced by the stomach's parietal cells, it's converted into active pepsin. Pepsin plays a crucial role in protein digestion, breaking down large protein molecules into smaller peptides.
Chymosin's Role (Primarily in Infants)
Chymosin, also known as rennin, is an enzyme primarily important in infant digestion. It helps coagulate milk, making it easier to digest. While present in peptic cells, its role diminishes in adulthood.
Location and Function within the Stomach
Peptic cells reside within the gastric glands, which are found in the lining of the stomach. These glands are responsible for producing the various components of gastric juice, essential for digestion.
- Gastric Glands: The location of peptic cell activity.
- Pepsinogen Secretion: The primary function, leading to protein digestion.
- Chymosin Secretion (Infancy): A secondary function, aiding milk digestion in infants.
The references highlight the importance of peptic cells in the overall digestive process, particularly in protein breakdown. The conversion of pepsinogen to pepsin is a key step in this process, requiring the acidic environment created by parietal cells. In summary, peptic cells are essential components of the stomach's digestive machinery.
