Prostaglandin E2 (PGE2) is a member of the prostaglandin family of lipid compounds. PGE2 is produced in response to various physiological stimuli and acts as a potent mediator of inflammation, pain, and fever.
PGE2 is synthesized from arachidonic acid, which is released from cell membranes by the action of phospholipase A2. The conversion of arachidonic acid to PGE2 is catalyzed by the enzyme cyclooxygenase (COX), which exists in two forms: COX-1 and COX-2. COX-1 is a constitutive enzyme that is present in most tissues and is involved in the regulation of normal physiological processes, such as the regulation of blood flow and the protection of the gastric mucosa. COX-2, on the other hand, is an inducible enzyme that is produced in response to various inflammatory stimuli and is involved in the production of PGE2.
PGE2 acts on specific receptors (EP1-4) to produce a variety of physiological responses, including the regulation of blood flow, the regulation of the immune response, the modulation of pain and inflammation, and the regulation of fever. PGE2 also plays a role in the regulation of sleep, appetite, and the reproductive system.
PGE2 has both beneficial and harmful effects on the body. In small amounts, PGE2 is involved in the regulation of various physiological processes and helps to maintain homeostasis. In larger amounts, however, PGE2 can contribute to the development of various diseases, such as inflammation, pain, and fever. Inhibitors of COX-2, such as nonsteroidal anti-inflammatory drugs (NSAIDs), are commonly used to reduce the production of PGE2 and to treat inflammation, pain, and fever.