ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: α2-Adrenergic receptors labelled by [3H]clonidine (α2-agonist) can be solubilized from the rat brain in a form sensitive to guanine nucleotides with a zwitterionic detergent, 3-[3-(cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS). About 40% of the original [3H]CLO binding sites in the membranes were solubilized with 6 mM CHAPS. Separation of the soluble [3H]CLO-bound complex was performed by the vacuum filtration method using polyethylenimine-treated GF/B filters. Solubilized [3H]CLO binding sites retained the same pharmacological characteristics of membranebound α2-adrenergic receptors. Scatchard plots of [3H]CLO binding to solubilized α2-receptors were curvilinear, indicating the existence of the two distinct binding components. Solubilized receptors were eluted as a single peak from Bio-Gel A-1.5 m column with a Stokes radius of 6.6 nm. The isoelectric point was 5.6–5.8. Regulations of the receptor binding by guanine nucleotides, monovalent cations, and sulfhydryl-reactive agents were maintained intact in the soluble state, whereas those by divalent cations were lost. The apparent retention of receptors and guanine nucleotide binding regulatory component(s) in the soluble state may allow a investigation of the regulation mechanisms of the brain α2-adrenergic receptor system at the molecular level.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1985.tb08805.x
