Determination of androgen receptors in human benign prostatic hypertrophy with two synthetic radiolabeled ligands.

Nuclear and cytosolic androgen receptor concentrations in tissues of human benign prostatic hypertrophy (BPH) were determined by use of methyltrienolone (R-1881) and 7 alpha,17 alpha-dimethyl-19-nortestosterone (DMNT) as radiolabeled ligands. Cytosolic R-1881-binding sites were 46.1 +/- 43 fmol/mg protein and nuclear R-1881-binding sites were 51.8 +/- 42 fmol/mg protein. DMNT-binding sites in cytosol were 44.3 +/- 38 fmol/mg protein and in nuclear extract 73.4 +/- 64 fmol/mg protein. No significant correlation was found between the number of R-1881- and DMNT-binding sites in either cytosol or nuclear extracts. Cytosolic or nuclear androgen receptor content was not significantly correlated with the percentage of epithelial or stromal cells as determined from the corresponding histological sections. In BPH tissue with marked cystic degeneration, very low androgen receptor levels were found.