Histamine is a naturally occurring compound synthesized in the body. It is a low molecular weight biogenic amine. It has been identified as a toxic agent which causes allergic reactions.
It is derived from amino acid histidine by the action of histidine decarboxylase. Histamine is found within granules of mast cells. basophils and platelets. It is concentrated especially in skin, gastrointestinal tract and lung.
Indigenous histamine is produced in the human body mainly in mast cells and is released as a result of response to allergens.
Mast cells release histamine in response to a number of stimuli, including mechanical stimulation, anaphylatoxins formed from complement and certain neuropeptides.
The mechanisms of histamine toxicity involves mediators known as histamine receptors such are responsible for the development of the various symptoms.
Histamines, one in the bloodstream has a number of effects. Histamine relaxes the smooth muscle of the arterioles leading to the wounded area, so increasing its blood flow.
It causes the cells of the capillary walls to draw away from one another, so that the capillaries become leaky. More plasma escapes from capillaries and collects in the site of the wound. The fluid causes the site of the wound to swell and become warm.
Allergic reactions to foods contain histamine depend not only how much histamine is, but also on individual threshold and the ability to breakdown histamine.
Histamine in human body
