Histamine Mechanism

Histamine exerts its actions by combining with specific cellular histamine receptors. The four histamine receptors that have been discovered are designated H1 through H4.

TypeLocationFunction
H1 histamine receptorFound on smooth muscle, endothelium, and central nervous system tissueCauses vasodilation, bronchoconstriction, bronchial smooth muscle contraction, separation of endothelial cells (responsible for hives), and pain and itching due to insect stings; the primary receptors involved in allergic rhinitis symptoms and motion sickness.
H2 histamine receptorLocated on parietal cellsPrimarily stimulate gastric acid secretion
H3 histamine receptorFound on central nervous system and to a lesser extent peripheral nervous system tissueDecreased neurotransmitter release: histamine, acetylcholine, norepinephrine, serotonin
H4 histamine receptorFound primarily in the basophils and in the bone marrow. It is also found on thymus, small intestine, spleen, and colon.Plays a role in chemotaxis.

Further Reading


This article is licensed under the Creative Commons Attribution-ShareAlike License. It uses material from the Wikipedia article on "Histamine" All material adapted used from Wikipedia is available under the terms of the Creative Commons Attribution-ShareAlike License. Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.

Last Updated: Feb 1, 2011

Read in | English | Español | Français | Deutsch | Português | Italiano | 日本語 | 한국어 | 简体中文 | 繁體中文 | العربية | Dansk | Nederlands | Finnish | Ελληνικά | עִבְרִית | हिन्दी | Bahasa | Norsk | Русский | Svenska | Magyar | Polski | Română | Türkçe
Comments
The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News-Medical.Net.
Post a new comment
Post