noun, plural: prostaglandins D
Prostaglandin is an eicosanoid that is derived from unsaturated 20-carbon fatty acids, such as arachidonic acid, through the cyclooxygenase pathway. There are several prostaglandins and they are designated by appending a letter, i.e. from A to I, to indicate the type of substituents found on the hydrocarbon skeleton. There are four major types of prostaglandins produced biosynthetically: prostaglandin E2 (PGE2), prostacyclin (PGI2), prostaglandin D2 (PGD2) and prostaglandin F2α (PGF2α).
PGD series is a group of prostaglandin naturally produced in the body, such as mast cells, brain, and airways. PGD2 is one of the most biologically active. PGD2 (IUPAC name: 9α,15S-dihydroxy-11-oxo-prosta-5Z,13E-dien-1-oic acid), with a chemical formula of C20H32O5 , is a prostaglandin that when bound to the receptors, PTGDR and CRTH, regulates body temperature during sleep, plays a role in pain perception, and regulates inflammation and allergies. It also causes vasoconstriction. PGD2 is the major prostaglandin produced by the mast cells. It recruits type 2 helper T cells, eosinophils, and basophils.
PGD2 is the principal cyclooxygenase metabolite of arachidonic acid. It is released upon activation of mast cells and is also synthesized by alveolar macrophages. Among its many biological actions, the most important are its bronchoconstrictor, platelet-activating-factor-inhibitory, and cytotoxic effects.