Histamine - Plasma
Histamine plays a crucial role in the immune response and high levels are seen in allergic disorders and mast cell disorders. Histamine is released from mast cells which are immune cells present mainly in the skin, lining of the intestine and air passages as well as the bone marrow. Mast cells are crucial in the body's normal injury response as well as allergic reactions. The release of histamine is responsible for a number of symptoms associated with an allergic reaction.