Inflammatory Mediator Molecules
Inflammatory mediator molecules are chemicals that control the inflammatory process. Some mediators are released when tissue cells are damaged, while others are released by the blood or leukocytes in response to tissue damage. The major classes of inflammatory mediators are such as prostaglandins, such as interleukin (IL) and such as bradykinin. Eicosanoids have many functions including major roles in inflammation and fever. They are produced by mast cells from the fatty acid acid. By affecting the availability and reactivity of arachidonic acid we can control the heat, pain and swelling associated with inflammation. Examples include: Prostaglandins: mediate vasodilatation, thermoregulation and pain sensation Thromboxanes: vasoconstriction & platelet aggregation Leukotrienes: increase membrane permeability & platelet aggregation act to inhibit the release of arachidonic acid from the membrane of cells, thereby making it unavailable for the production of inflammatory mediator chemicals. block the activity of the enzymes that control the anabolism of arachidonic acid- based inflammatory mediators. Cytokines are important in cell signalling and act to change the behaviour of other cells. Most importantly is the interleukin mediators. They promote the development and differentiation of B & T lymphocytes. Kinins act to cause local vasodilation and contraction of smooth muscles. It acts to decrease blood pressure. Bradykinin is the most well-known of the kinins. Histamine is considered the most important chemical mediator of inflammation. It is released by cells in response to damage. Histamine acts to increase vasodilatation, vascular permeability and is a strong chemotaxic molecule. We can decrease the production of histamine in the body by using a group of pharmaceuticals known as H-1 receptor agonists. These drugs in effect block histamine from binding to receptors in target cells, thereby reducing the effects of histamine on the blood vessels and tissue.
Signs and Symptoms of Inflammation
The process of inflammation is consistent, but the amount of inflammation reflects the intensity and duration of tissue damage. Inflammation can be quite mild, or it can be severe, it can be localized, or it can be systemic. The outward signs of inflammation are an indication of the severity and extent of injury to body tissues.
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