title: Solubilization of dopamine D2 receptors with a zwitterionic detergent DCHAPS.
abstract: Dopamine D2 receptors were solubilized from synaptosomal membranes of the bovine caudate nucleus using a novel zwitterionic detergent 3-[(3-deoxycholamidopropyl)-dimethylammonio]-1-propane sulfonate (DCHAPS) supplemented with 1,2-propylene glycol. Optimal conditions for solubilization were: 0.12% DCHAPS, 5% 1,2-propylene glycol, 8 mg/ml membrane protein, 30 min, 4 degrees and the yield of the D2 receptors was 36.1%. The soluble extract retained the ability to bind [3H]spiperone. This binding was of high affinity (Kd = 2.28 +/- 0.16 nM), reversible and saturable (Bmax = 1.68 +/- 0.06 pmol/mg protein). The order of potencies of dopamine agonists and antagonists for inhibition of binding, paralleled that observed on membrane-bound D2 receptors (correlation factor r = 0.96). The stereo-specificity of solubilized receptors toward the pairs (+)-[(-)butaclamol, cis(Z)-]trans(E)flupenthixol and dihydroergosine/dihydroergosinine was pronounced.
mesh_terms: D000818:Animals; D002417:Cattle; D002793:Cholic Acids / Q000494:pharmacology*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003902:Detergents / Q000494:pharmacology*; D066298:In Vitro Techniques; D007700:Kinetics; D011954:Receptors, Dopamine / Q000302:isolation & purification* / Q000378:metabolism; D017448:Receptors, Dopamine D2; D012965:Sodium Chloride / Q000494:pharmacology; D012995:Solubility; D013134:Spiperone / Q000378:metabolism; D013237:Stereoisomerism; D013501:Surface-Active Agents / Q000494:pharmacology*
chemical_list: D002793:Cholic Acids; D003902:Detergents; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D013501:Surface-Active Agents; C050286:3-((3-deoxycholamidopropyl)dimethylammonio)-1-propane; D012965:Sodium Chloride; D013134:Spiperone