Prostaglandins are synthesized by cyclooxygenase enzymes, which initially convert arachidonic acid to Prostaglandin H2. Prostaglandin synthases then convert Prostaglandin H2 to Prostaglandin E2 (PGE2). PGE2 is a vasodilator and is associated with several disease states including inflammation, arthritis, endometriosis, and a variety of cancers. PGE2 is identical across all species and we can measure PGE2 from sources other than humans. BioVendor multispecies PGE2 immunoassay has been validated for saliva, urine, serum, EDTA, and heparin plasma samples and for tissue culture samples.