Prostaglandin has significant constitutive role on gastric acid secretion – explain the mechanism


Prostaglandins are locally produced signaling molecules derived from arachidonic acid, an essential fatty acid. In the stomach, prostaglandins are mainly synthesized by gastric parietal cells, the primary acid-secreting cells. The enzyme cyclooxygenase-1 (COX-1) is responsible for prostaglandin production in these cells.

Prostaglandins, particularly Prostaglandin E (PGE), play a significant role in gastric acid secretion. They are involved in the regulation of various gastric functions that contribute to gastric protection. 

Mechanism 

  1. PGE2 and PGI2 have significant role in gastric acid secretion.
  2. Prostaglandins bind with EP receptor (a GPCR) and stimulate the Gi protein.
  3. Gi pathway is responsible for the inhibition of Adenylyl Cyclase Pathway. 
  4. So, AMP can not converted to cyclic AMP thereby reducing the PKA and decrease in Gastric Acid Secretion by Proton Pump. 
Prostaglandins decrease stomach acid production while also stimulating the release of protective mucus in the gastrointestinal tract. This dual action helps to maintain the stomach’s pH balance and protect the stomach lining from the corrosive effects of gastric acid.



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