Steroid-binding properties of the androgen receptor of rat seminal vesicle.

The binding of 19 steroids to the vesicular androgen receptor has been studied under cell-free conditions. Rate constants of association and dissociation were determined for the binding of 3H-5 alpha-dihydrotestosterone (3H-DHT) and 3H-testosterone with the receptor. The Scatchard-analyses of the two reactions were also performed to determine the equilibrium binding constants. The values obtained were significantly different from those calculated from the kinetic constants, which was due to the relative inaccuracy of equilibrium analysis in our system.