Mechanisms underlying histamine release from mast cells

Histamine is the most important inflammatory mediator in urticaria.Histamine release from mast cells plays a key role in the pathogenesis of allergic disorders and non-allergic reactions.Researches have shown that mast cells release histamine via both immunological and non-immunological pathways.Many substances participate in the process of histamine release.The typical way to activate mast cells is through specific IgEs.Both anti-high affinity IgE receptor(FceRI)antibodies and anti-IgE antibodies are involved in histamine release by mast cells in chronic idiopathic urticaria.Thrombin generated during blood coagulation can activate proteinase-activated receptors,which mediate mast cell adhesion to fibronectin,and induce histamine release from mast cells.Genetic factors,neurological and psychiatric factors,as well as physical factors are also involved in histamine release by mast cells in urticaria. Key words: Urticaria; Mast cells; Histamine