Histamine inhibits tumor necrosis factor alpha release by mast cells through H2 and H3 receptors.

Histamine was one of the first inflammatory mediators thought to be important in the pathophysiology of asthma, but it is not now thought to be a mediator with primary importance in airway constriction. However, histamine has several effects that may be relevant. One of these effects, its immunoregulatory role, has been largely ignored in asthma. Thus… (More)