Merck Millipore Prostanoid Receptor Membrane Preparation

Prostanoids bind to a family of 8 GPCRs to exert their biological effects (Narumiya and FitzGerald, 2001). The prostaglandin PGE2 causes pain, vasodilation, immunosuppression of T cells, bone resorption and promotion of carcinogenesis. Four related GPCRs, EP1, EP2, EP3 and EP4, each bind to PGE2, but the different G protein coupling status of each receptor leads to distinct biological effects. Further diversity is generated by alternative splicing; the human gene for EP3 generates 9 alternatively spliced mRNAs encoding 8 isoforms of EP3 (Kotani et al., 1997). These isoforms of EP3 vary in sequence at their C-termini, and differ in their ability to couple to Gs, Gq or Gi (Kotani et al., 1995). EP3 is required for fever induced by pyrogens, a response long attributed to prostaglandins by the antipyretic action of aspirin and other COX inhibitors (Ushikubi et al., 1998). Chemicon's EP3 membrane preparations are crude membrane preparations made from our proprietary stable recombinant cell lines to ensure high-level of GPCR surface expression; thus, they are ideal HTS tools for screening of antagonists of EP3 interactions and its ligands. The membrane preparations exhibit a Kd of 1.56 nM for [3H]-PGE2. With 1.5 nM [3H]-PGE2, 5 µg/well and 10 µg/well EP3 Membrane Prep typically yield greater than 10 and 20-fold signal-to-background ratios, respectively.