H₂ receptor

H2 receptors positively coupled to adenylate cyclase via Gs. It is a potent stimulant of cAMP production. It increases the intracellular Ca2+ concentrations and release Ca2+ from intracellular stores.

The drug Betazole is an example of a Histamine H2 receptor agonist.

Location

 * Gastric parietal cells (oxyntic cells)
 * Vascular smooth muscle
 * Neutrophils
 * Central nervous system
 * Heart
 * Uterus

Response

 * Stimulation of gastric acid secretion
 * Smooth muscle relaxation
 * Inhibit antibody synthesis, T-cell proliferation and cytokine production

H2-receptor agonists and antagonists
see H2-receptor agonist and H2-receptor antagonist