Allergic mediators released from mast cells

Antigens can cause degranulation of mast cells resulting in allergic reactions. Some of the allergic mediators released from mast cells are preformed whereas others are synthesised on demand.

Preformed mediators
ECF-A Eosinophil chemotactic factor  of Anaphylaxis – attracts eosinophils to the site
NCF – A Neutrophil chemotactic factor – attracts neutrophils to the site
Histamine Vasodilation and bronchospasm
Heparin Promotes phagocytosis
Newly synthesised mediators
Prostaglandin Vasoconstriction and bronchospasm
Leukotriene Vasoconstriction and bronchospasm
Thromboxane A2 Vasoconstriction and platelet aggregation
PAF Platelet Activating Factor – bronchospasm, platelet aggregation, chemotaxis of neutrophils, eosinophils
TNF alpha Tumour necrosis factor – transmigration of eosinophils and neutrophils