Mast Cells: Your Body's Key Players in Inflammation and Allergy

The substance that responds to injury, infection, or allergy by producing and releasing substances including heparin, histamine, and serotonin is known as *mast cells*. These cells are a type of white blood cell found in connective tissues throughout the body. When activated, mast cells degranulate, releasing their pre-formed mediators, which include heparin, histamine, serotonin, and other inflammatory substances. These mediators play important roles in the body's immune response and in the development of allergic reactions.