When antigens bind to antibodies on mast cell surfaces, degranulation occurs, triggering anaphylaxis. What do the granules of mast cells release that causes this reaction?

Explanation

Mast cell granules contain vasoactive mediators, such as histamine, which increase blood vessel permeability and lead to the symptoms of anaphylaxis. While lysosomes and proteolytic enzymes are cellular components, they are not responsible for the anaphylactic response. Lymphotoxins are produced by lymphocytes and are unrelated to mast cell degranulation.