The function of chemical substances such as histamine and leukotrienes would be to stimulate inflammation. Leukotrienes is an example of eicosanoids which play a key role in the pathogenesis of inflammation. They are synthesized in the leucocytes from arachidonic acid via the actions of 5-lipoxygenase. The release of histamine serves as an important part of the body's immune response; when the body comes into contact with an allergen, such as pollen or animal dander, histamine is released by the body to the site of contact and triggers inflammation.
