This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Cellular action

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Histamine acts via two types of target receptor:

  • H1:
    • activation causes an increase in cytosolic calcium
    • found predominantly on smooth muscle of gut and lung where it promotes contraction; bronchial histamine has a role in asthma
    • in vessels, an important role in inflammation as epitomised by the triple response:
      • vasodilatation of arterioles
      • vasodilatation of pre-capillary sphincters
      • increased permeability of post-capillary venules
  • H2:
    • activation causes an increase in adenylate cyclase
    • in the stomach, H2 receptors stimulate the production of acid by parietal cells
    • in the heart, H2 receptors cause positive inotropy and chronotropy

It may also act indirectly, as it does in the stimulation of free nerve endings to cause pruritus.


Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.