CHARACTERIZATION AND HORMONAL-CONTROL OF ANDROGEN RECEPTOR IN HAMSTER SEBACEOUS GLANDS

[摘要] The costovertebral organs [CVO] and seminal vesicles [SV] of the hamster exhibit high saturable androgen uptake. The physicochemical characteristics of the cytoplasmic androgen receptor present in these tissues were determined and compared to those obtained in rat prostate [P]. Using the synthetic androgen R 1881 [methyltrienolone] as a radioactive ligand, it was shown that the affinity of this compound for the cytosol CVO receptor [Kd = 0.7 .+-. 0.1 nm] is similar to that for the cytosol SV receptor [Kd = 2.4 .+-. 0.9 nM] in hamsters and the cytosol P receptor [Kd = 0.6 .+-. 0.1 nM] in rats. The hormonal specificity of binding in these tissues is restricted to androgens. Testosterone and dihydrotestosterone have the same relative binding affinity in CVO and SV compared to R 1881. Following castration, the total number of androgen binding sites, as measured by an exchange assay with R 1881, decreases rapidly and parallels with a fall in lipogenic activity. Administration of an androgen rapidly restores binding capacity.