Binding characteristics of 3H-prazosin to rat brain alpha-adrenergic receptors.

3H-Prazosin binding to membranes from rat brain is saturable, Bmax, 77 fmol/mg protein, of high affinity, KD, 0.28 nM and with a drug specificity indicating that it labels alpha-adrenergic receptors. The ranking of alpha-antagonists for these binding sites suggests that 3H-prazosin may be useful in identifying a subpopulation of alpha-receptors (alpha1) in the central nervous system.