There are four known histamine receptors:
There are several splice variants of H3 present in various species. Though all of the receptors are 7-transmembrane g protein coupled receptors, H1 and H2 are quite different from H3 and H4 in their activities. H1 causes an increase in phosphoinositol hydrolysis, H2 stimulates gastric acid secretion, and H3 mediates feedback inhibition of histamine.
- Hill SJ, Ganellin CR, Timmerman H, Schwartz JC, Shankley NP, Young JM, Schunack W, Levi R, Haas HL (1997). "International Union of Pharmacology. XIII. Classification of histamine receptors". Pharmacol. Rev. 49 (3): 253–78. PMID 9311023.
- Hofstra CL, Desai PJ, Thurmond RL, Fung-Leung WP (2003). "Histamine H4 receptor mediates chemotaxis and calcium mobilization of mast cells". J. Pharmacol. Exp. Ther. 305 (3): 1212–21. PMID 12626656. doi:10.1124/jpet.102.046581.