this video is a absoloutely amazing way of understanding wtf is happening
https://www.youtube.com/watch?v=oAEwnbi9Cio
There are things known as secretagons, these act as stimulators of certain secretion there are 3 POSITIVE secretagons in the stomach for gastric acid secretion and 2 NEGATIVE
the Proton pump involves passage of K+ into the parietal cell in exchange for H+ out into the lumen of the stomach this H+ out is the gastric acid the following things we are talking about all effect this pathway and some inhibit whereas others stimulate it.
POSITIVE (agonists)
Histamine
Acetylcholine
Gastrin
Histamine (works on H2 receptors)
Released by enterochromaffin like (ECL) cells lying close to parietal cell
Release is increased by action of gastrin and acetylcholine
ACTION OF HISTAMINE
• Stimulates parietal cell activity via its H2 receptors