Solubilization and characterization of a [3H]hemicholinium-3 binding site in rat brain.
A sodium-dependent high-affinity [3H]-hemicholinium-3 ([3H]HCh-3) binding site was solubilized from rat striatal synaptic plasma membranes by 0.2% deoxycholate. Deoxycholate solubilization of the [3H]HCh-3 binding site was dependent upon both detergent concentration and ionic strength of the solubilization medium. Specific [3H]HCh-3 binding to the solubilized preparation was both sodium- and chloride-dependent and saturable, exhibiting an affinity of 14.2 nM and a capacity (Bmax) of 695 fmol/mg protein. Choline and other analogs inhibited specific [3H]HCh-3 binding to the solubilized preparation in a concentration-dependent manner with the similar rank order of potency observed in crude synaptic membranes. Treatments known to disrupt both protein and lipid moieties resulted in diminished specific [3H]HCh-3 binding. These results suggest that the characteristics of the solubilized [3H]HCh-3 binding site are similar to those of the membrane-bound site.
Yamada
K
K
Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Saltarelli
M D
MD
Coyle
J T
JT
D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000378:metabolism*; D002712:Chlorides / Q000494:pharmacology; D002794:Choline / Q000031:analogs & derivatives / Q000494:pharmacology; D003342:Corpus Striatum / Q000378:metabolism; D003840:Deoxycholic Acid; D006426:Hemicholinium 3 / Q000378:metabolism*; D008297:Male; D009994:Osmolar Concentration; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000494:pharmacology; D012995:Solubility; D013570:Synaptic Membranes / Q000378:metabolism
D002712:Chlorides; D003840:Deoxycholic Acid; D006426:Hemicholinium 3; D012964:Sodium; D002794:Choline