 PGD2, PGE2, PGF2alpha, and PGI2 have binding and stimulating potencies that are >1,000-fold weaker than I-BOP and therefore are assumed not to have appreciable ability to stimulate TP in vivo.20-Hydroxyeicosatetraenoic acid (20-HETE) is a full agonist and certain isoprostanes, e.g.8-iso-PGF2 alpha and 8-iso-PGE2, are partial agonists of the TP receptor.