Histamine Pathway

The histamine pathway encompasses the synthesis, storage, release, receptor-mediated actions, and metabolism of histamine. Histamine, a biogenic amine, plays crucial roles in immune responses, neurotransmission, gastric acid secretion, and inflammation. It exerts its effects primarily through four G protein-coupled receptors (H1R–H4R), each with distinct tissue distributions and physiological functions. The pathway involves L-histidine decarboxylase for synthesis, mast cells and basophils for storage, and histamine-N-methyltransferase (HNMT) and diamine oxidase (DAO) for metabolism. Antihistamines targeting different receptor subtypes are widely used to treat allergies, reduce gastric acidity, and potentially address neurological disorders or chronic inflammatory diseases.

Other names

Histamine signaling pathway

Multiple mechanisms depending on the specific drug and target within the pathway, including receptor antagonism, inverse agonism, and enzyme inhibition.