A competitive assay that can be used for quantification of PGD₂.

• Measure PGD₂ in multiple sample types
• Assay 24 samples in triplicate or 36 samples in duplicate
• Measure PGD₂ levels down to 55 pg/ml
• Incubation: 18 hours
• Development: 90 to 120 minutes
• Read: Colorimetric at 405 to 420 nm

Prostaglandin D2 (PGD₂) is biosynthesized in the brain by a soluble, 26 kDa glutathione-independent lipocalin-type PGD₂ synthase. This PGD₂ accumulates in the cerebrospinal fluid (CSF), where it induces physiologic sleep in rats and humans. PGD₂ is also synthesised in mast cells and leukocytes by a cellular, myeloid-type, glutathione-dependent PGD synthase. This PGD₂ which is formed in the intracellular and vascular compartments is rapidly metabolised to 11β-PGF_2α and other metabolites.

Measurement of the parent eicosanoid PGD₂ is appropriate in cell culture lysates and in CSF, where concentrations of several hundred pg/ml have been measured. Cayman’s PGD₂ ELISA kit is a competitive assay that can be used for quantification of PGD₂ in cell culture lysates and enzymatic reactions.