3H-Clonidine binding to membranes of platelets prepared under physiological conditions

A reproducible binding assay has been established to measure alpha 2-adrenoreceptors on membranes of human platelets prepared under physiological conditions. Washed platelet suspensions were obtained from fresh blood by a modified method (Mustard et al., 1972) and membranes were prepared by mechanical homogenization. 3H-clonidine, a selective alpha 2-adrenoreceptor agonist was selected as the ligand in a concentration range of 2-64 nM. Specific …