CHEMBL3887793

Functional Assay: [35S]GTPgammaS functional assays were conducted using freshly thawed u-receptor membranes (Perkin Elmer, Shelton, Conn.). Assay reactions were prepared by sequentially adding the following reagents to binding buffer (100 mM NaCl, 10 mM MgCl2, 20 mM HEPES, pH 7.4) on ice (final concentrations indicated): membrane protein (0.026 mg/mL), saponin (10 mg/mL), GDP (3 mM) and [35S]GTPgammaS (0.20 nM; Perkin Elmer, Shelton, Conn.). The prepared membrane solution (190 ul/well) was transferred to 96-shallow well polypropylene plates containing 10 ul of 20x concentrated stock solutions of the agonist [D-Ala2, N-methyl-Phe4 Gly-ol5]-enkephalin (DAMGO) prepared in dimethyl sulfoxide (DMSO). Plates were incubated for 30 min at about 25° C. with shaking. Reactions were terminated by rapid filtration onto 96-well Unifilter GF/B filter plates (Perkin Elmer, Shelton, Conn.) using a 96-well tissue harvester (Perkin Elmer, Shelton, Conn.) followed by three filtration washes with 2001 of ice-cold binding buffer.