Merck Millipore M3 Membrane Preparation Human Recombinant

The muscarinic acetylcholine receptor (mAChR) family consists of five GPCRs that mediate some of the neurotransmission functions of acetylcholine in the CNS and the periphery. The M1, M3 and M5 receptors couple to Gq to mobilize intracellular calcium, whereas the M2 and M4 receptors couple to Gi/o to inhibit cAMP production (Caulfield and Birdsall, 1998). M3 is expressed prominently in smooth muscle, and plays a primary role in mediating mAChR agonist-induced contractility. Mice lacking M3 have dilated pupils, which indicates a role for M3 in regulating tone of the pupillary sphincter muscle. In addition, Msub3 plays a role in feeding, as indicated by the lean and hypophagic phenotype of M3-null mice (Wess, 2004). Chemicon's M3 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 M3 interactions with 4-DAMP. The membrane preparations exhibit a Kd of 0.72-1 nM for [3H]-4-DAMP. With 10 µg/well M3 Membrane Prep and 0.75 nM [3H]-4-DAMP, a greater than 4-fold signal-to-background ratio was obtained.