How Our Stomach Defends Itself Against Protein Digesting Enzymes

Our stomach has to produce a new layer of mucus regularly after every two weeks or else it will digest itself.

Our stomach has to perform a very important and difficult task of digesting food which involves the secretion of powerful acids and enzymes. The stomach is the most dilated part of the digestive tube, and is situated between the end of the oesophagus and the beginning of the small intestine.

The stomach is made up of proteins and astonishingly, it contains powerful protein-digesting enzymes. So if the stomach wall doesn’t have any protection, the enzymes will digest the stomach itself. The mucus membrane itself is very thick and velvety. It has a peculiar honeycomb appearance with shallow depressions and it is made of water and protein.

All mucous producing membranes are termed as mucosa(s), and the epithelium of the stomach is called the Gastric mucosa. The mucosa generates so much mucus that this layer insulates itself from the stomach thus saving it from digestive enzymes. This layer of mucus can protect the stomach pretty well but it is not impermeable, as the cells of the mucosa are constantly being damaged and have an average lifespan of only few days. The basal layer beneath the epithelium must produce enough new cells to replace the entire gastric mucosa every week.

If the rate of destruction is too high, perhaps because of insufficient mucus or the rate of replacement is too low, the acid and pepsin may begin to destroy the underlying tissues of the stomach wall, causing an ulcer.

[Source: WIKIPEDIA]