Solubilization and characterization of the nitrendipine receptor in rat brain.
The nitrendipine receptor associated with the voltage-dependent calcium channel in rat brain was solubilized by detergent extraction and sonication. The detergent solution used for extraction consisted of 10 mM 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), 0.25% (wt/vol) polyoxyethylene 20 cetyl ether (Brij 58), and 0.025% (wt/vol) polyoxyethylene 17 cetyl stearyl ether (Lubrol WX) in the presence of 30% (wt/vol) glycerol as a stabilizer. The molecular weight of the receptor was estimated to be 1,800K by Sephacryl S-500 gel filtration and 800K by sucrose density gradient sedimentation. The equilibrium dissociation constant of [3H]nitrendipine to the solubilized receptors was 5.6 nM, which is approximately 10 times that of the membrane-bound receptor. The binding of nitrendipine to the receptor was inhibited noncompetitively by the structurally unrelated calcium channel inhibitors verapamil and prenylamine; their concentrations for 50% inhibition were both 1.0 X 10(-7) M, and they caused maximal inhibitions of 70 and 100%, respectively.
D000818:Animals; D001923:Brain Chemistry; D015220:Calcium Channels; D002499:Centrifugation, Density Gradient; D002850:Chromatography, Gel; D003902:Detergents; D008970:Molecular Weight; D009568:Nitrendipine / Q000378:metabolism; D011299:Prenylamine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000302:isolation & purification* / Q000378:metabolism; D012995:Solubility; D014700:Verapamil / Q000494:pharmacology
D015220:Calcium Channels; D003902:Detergents; D011978:Receptors, Nicotinic; D009568:Nitrendipine; D014700:Verapamil; D011299:Prenylamine