Influence of divalent cations on androgen and estrogen binding in human prostatic tissue

The influence of divalent cations on estrogen and androgen binding in human benign prostatic hypertrophy (BPH) was investigated. Two tissue types were detected. In type I, important estradiol binding increase in the presence of Mg++ and good evidence of the androgen receptors were noticed. Type II tissues were characterized by weak or inhibitory effect of Mg++ and, poor detection of the androgen receptors in some of the buffers used. Zn++ inhibited estradiol binding. Effects of chelators leaving some endogenous divalent cations in the medium were investigated. For both binding activities no difference could be established between type I and type II tissues. One exception was a somewhat increased androgen binding for type II when endogenous Mg++ was present. Strong inhibition of estradiol binding in the presence of EDTA + Mg++ always occurred. Influence of divalent cations on steroid binding measurements in BPH tissues is discussed.