New concepts of histamine receptors and actions
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Updated: Sep 26, 2026

Basophil Activation Test for Allergy Diagnosis
Published on: May 31, 2021
1Division of Rheumatology, Immunology, and Allergy, Georgetown University Medical Center, GL-020 Gorman Building, 3800 Reservoir Road, Washington, DC 20007-2197, USA. baraniuj@georgetown.edu
Abstract:
Histamine and antihistamines are so deeply woven into the fabric of allergic diseases that it is sometimes difficult to see how this field could advance beyond our current, potent histamine H1-receptor drugs. Investigations of other actions of histamine and the identification of H2, H3, and now H4 receptors have suddenly reignited the search for new mono- and multi-receptor-specific agonists and antagonists. There is great excitement due to preliminary findings that H3 receptors act as neural inhibitory autoreceptors, and H4 receptors might modulate immune cell functions.
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