Digitonin-solubilized histamine H1-receptors bind to polyethylenimine-treated glass-fibre filters.
The binding of [3H]mepyramine to histamine H1-receptors solublized from guinea-pig cerebellum by 1% digitonin could be assayed by adsorption of the receptor-bound [3H]ligand to glass-fibre filters pretreated with 0.3% polyethylenimine (PEI). Non-specific binding was higher than in parallel experiments in which the bound and free [3H]ligand was separated by gel-filtration on Sephadex G-25 columns, but the parameters characterizing the inhibition curves were otherwise similar. The PEI-treated filter method could also be used to assay [3H]-(+)-N-methyl-4-methyl-diphenhydramine ([3H]QMDP) binding to solubilized H1-receptors, but the level of non-specific binding was higher and was only satisfactorily defined by icotidine or temelastine. A particular utility of the PEI-treated filter assay will be in measurements of the kinetics of H1-receptor-ligand interactions.
Treherne
J M
JM
Department of Pharmacology, University of Cambridge, UK.
Young
J M
JM
D000818:Animals; D002850:Chromatography, Gel; D004072:Digitonin / Q000032:analysis*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D011094:Polyethyleneimine; D011738:Pyrilamine / Q000494:pharmacology; D011969:Receptors, Histamine H1 / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D013997:Time Factors
D011969:Receptors, Histamine H1; D011094:Polyethyleneimine; D011738:Pyrilamine; D004072:Digitonin