Pharmacology : Stomach And Proton-pump Inhibitors

Question 1

What protect the stomach wall from the acidity of its lumen ?

Answer 1

A mucous bicarbonate barrier situated above the epithelial junction.

Question 2

What is dyspepsia ? What does it cause ?

Answer 2

It is the excess acid production in the stomach. The high acid concentration can damage the stomach lining and result in ulcers.

Question 3

What is the main cause of peptic ulcers ?

Answer 3

Caused at 80% by H. Pylori. This bacteria survive in the acidic environment by attaching to sugar molecule and use the mucus layer as a protection. They can create a bubble in the mucous layer to neutralise acid thanks to urease.
They damage the mucous layer and also secret proteins and toxins interacting with stomach’s epithelial cells.

Question 4

What is GERD ?

Answer 4

Gastroesophageal reflux disease, characterised by heartburn. Is when the excess of acid in the stomach is forced into the oesophagus.

Question 5

How does the parietal cell produce acid ?

Answer 5

They possess proton pump that release H+ when activated. It will then bind to Cl- to create hydrochloride acid.
The proton pump can be activated by H2 receptors (via histamine) the M3 cholinergic receptors (via achetylcholine), and CCK2 receptors (via gastrin).