Affinity Labeling of Adenosine A1 Binding Sites

Abstract
The adenosine A1 receptors of sheep brain membranes have been identified by the specific binding of radiolabeled cyclohexyl [3H]adenosine ([3H]CHA). Pretreatment of membranes with periodate-oxidized CHA causes a dose-and time-dependent decrease in the number of binding sites. No decrease occurs when membranes are pretreated with CHA. Binding of [3H]CHA to the remaining sites occurs with the same characteristics as binding to the untreated receptor population.