Prostaglandin D2

Prostaglandin D2 (PGD2) is a prostaglandin that is produced by the enzyme Hematopoietic prostaglandin D synthase in the human body. It is one of the primary prostaglandins produced following inflammation or allergy and has a role in modulating the immune system and vasodilation.

Biosynthesis

Prostaglandin D2 is synthesized from prostaglandin H2 by the action of the enzyme Hematopoietic prostaglandin D synthase. This enzyme is found in various tissues, including the brain, heart, lung, and immune cells such as mast cells and Th2 cells.

Functions

PGD2 has several functions in the body. It is a potent vasodilator, meaning it can widen blood vessels and decrease blood pressure. It also acts as a bronchoconstrictor, causing narrowing of the airways in the lungs, which can lead to symptoms of asthma.

In the immune system, PGD2 is involved in the regulation of immune response. It can inhibit the migration of neutrophils to sites of inflammation, and promote the recruitment of eosinophils, which are involved in allergic reactions.

In the central nervous system, PGD2 promotes sleep and regulates body temperature.

Clinical significance

Due to its role in inflammation and immune response, PGD2 is implicated in a number of diseases, including asthma, allergic rhinitis, and atopic dermatitis. It is also involved in the pathogenesis of cardiovascular disease due to its effects on blood vessels.

Inhibitors of PGD2 synthesis or action are being investigated as potential treatments for these conditions. For example, laropiprant is a drug that blocks the action of PGD2 and is used in combination with niacin to treat high cholesterol.

See also

• Prostaglandin
• Inflammation
• Immune response
• Vasodilation
• Bronchoconstriction