https://doi.org/10.1351/goldbook.13442
Large connective tissue cell that contains inflammatory substances such as histamine, proteases (including tryptases, chymases, and carboxypeptidase A), heparin and chondroitin sulfate proteoglycans, and eicosanoid lipid mediators (the precursors of leukotrienes and prostaglandins). These substances are released in allergic reactions or in response to injury or inflammation.
Note: Mast cells are bound within tissues that interface with the external world such as the skin, respiratory or intestinal tract, as well as in other areas such as heart, synovium, and uterus. Mast cells do not circulate. The mast cell has binding sites on its surface for immunoglobulin E (IgE).