title: The binding of [3H]R-PIA to A1 adenosine receptors produces a conversion of the high- to the low-affinity state.
abstract: Kinetic evidence for negative cooperativity on the binding of [3H]R-PIA to A1 adenosine receptors was obtained from dissociation experiments at different ligand concentrations and from the equilibrium isotherm. The dissociation curves indicate that there is an apparent ligand-induced transformation of high- to low-affinity states of the receptor. At concentrations of 18.2 nM R-PIA or higher there was only found the low-affinity state of the receptor. In view of these results equilibrium binding data were analyzed by the usual two-state model (assuming that there is an interconversion between them) and by the negative cooperativity model employing the Hill equation.
authors.affiliation: Departament de Bioquimica i Fisiologia, Facultat de Quimica, Barcelona, Catalunya, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Casadó
authors.forename: J
authors.initials: J
authors.lastname: Mallol
authors.forename: E I
authors.initials: EI
authors.lastname: Canela
authors.forename: C
authors.initials: C
authors.lastname: Lluis
authors.forename: R
authors.initials: R
authors.lastname: Franco
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D010660:Phenylisopropyladenosine / Q000378:metabolism*; D011983:Receptors, Purinergic / Q000378:metabolism*; D012044:Regression Analysis; D013552:Swine
chemical_list: D011983:Receptors, Purinergic; D010660:Phenylisopropyladenosine