Pepsinogen

In biology class, we often hear biology teachers talk about pepsin and so on. Pepsin is a protease that facilitates digestion. It is secreted by the chief cells of the gastric mucosa in the stomach. Its function is to break down proteins in food into small peptide fragments. It is the only proteolytic enzyme in the stomach. Its optimum pH value is 1-2. Pepsinogen is the precursor of pepsin, which is synthesized by the chief cells of the oxyntic glands.

Pepsinogen will gradually become a more active protease, and pepsin will promote pepsin. Let me explain to you what pepsinogen is. I hope that through this article, you can learn more about it and stay healthy.

Pepsinogen is pepsin, which is divided into two subgroups according to its biochemical properties and immunogenicity. Components 1-5 have the same immunogenicity and are called pepsinogen I, which is mainly secreted by the chief cells and mucus neck cells of the fundic glands; components 6 and 7 are called pepsinogen II. In addition to being secreted by the chief cells and mucus neck cells of the fundic glands, the mucus neck cells of the pyloric glands of the cardia and antrum, and the upper duodenum can also produce pepsinogen II.

Pepsinogen is synthesized by the chief cells of the acid-secreting glands and is converted into pepsin by the action of hydrochloric acid or active pepsin in the gastric cavity, breaking down proteins into fat, peptone and a small amount of polypeptides. The optimum pH for the enzyme to function is 2. After entering the small intestine, the enzyme activity is lost. Stomach acid

Pepsinogen is synthesized by chief cells and stored in the cell as inactive zymogen granules. When the cell is filled with zymogen granules, it has a negative feedback effect on the production of new zymogen. Under the action of gastric acid, pepsinogen secreted into the gastric cavity separates a small molecule of polypeptide from the molecule and is converted into active pepsin. Activated pepsin also activates pepsinogen.

Pepsin can hydrolyze proteins in food. It mainly acts on the peptide bonds containing phenylalanine or tyrosine in protein and polypeptide molecules. Its main decomposition product is peptone, and it produces less polypeptides or amino acids. Pepsin can only work in a highly acidic environment, and its optimal pH is 2. As the pH increases, the activity of pepsin decreases, and when the pH rises above 6, the enzyme undergoes irreversible denaturation.

I believe that everyone now has more or less understanding of pepsinogen, and it also has certain clinical significance. The serum PG level reflects the morphology and function of the gastric mucosa in different parts of the body. Through the difference in its serum measurement values, it changes to varying degrees in various gastric diseases, providing reliable diagnostic value for clinical practice.