title: A study of the kinetics of the interaction of spiperone with binding sites on human mononuclear cells: existence of a heterogeneous population of spiperone binding sites.
abstract: The kinetics and equilibrium of the interaction of [3H]spiperone with binding sites on human mononuclear cells were studied using a competitive displacement of spiperone by ketanserin, sulpiride, haloperidol, (+)- and (-)-butaclamol. [3H]Spiperone binding sites on human mononuclear cells were shown to be not of the D2, but most probably of the 5-HT2 type. The process of [3H]spiperone binding to these sites conforms to the model of ligand interaction with two independent binding sites (the high-affinity site, Kd1 = 3 nM and the low-affinity site, Kd2 = 20 nM), thus suggesting heterogeneity of spiperone sites on mononuclear cells. We found that in contrast to high-affinity binding sites, low-affinity sites show an essentially lower stability during storage of mononuclear cells.
authors.affiliation: A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, M.V. Lomonosov Moscow State University, USSR.
authors.forename: S V
authors.initials: SV
authors.lastname: Zaitsev
authors.forename: A A
authors.initials: AA
authors.lastname: Koshkin
authors.forename: I I
authors.initials: II
authors.lastname: Izumrudova
authors.forename: S D
authors.initials: SD
authors.lastname: Varfolomeev
mesh_terms: D001665:Binding Sites; D002478:Cells, Cultured; D006801:Humans; D007700:Kinetics; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D011985:Receptors, Serotonin / Q000378:metabolism; D013134:Spiperone / Q000378:metabolism*
chemical_list: D011985:Receptors, Serotonin; D013134:Spiperone