tcsc2891 Cyproterone (acetate)

Cyproterone acetate is an androgen receptor (AR) antagonist with IC50 of 7.1 nM, as well as a weak progesterone receptor agonist with weak pro-gestational and glucocorticoid activity.

Target: Androgen Receptor

Cyproterone acetate clearly shows antagonistic properties, while being a partial agonist also, showing agonism for the AR, with EC50 of 4.0 μM, at relatively high concentrations [1]. In the presence of 10 nM Testosterone, low concentrations of Cyproterone acetate inhibits T-stimulated transcription of 3XHRE-LUC, but at higher concentrations, transcription is stimulated. LH levels in Cyproterone acetate-treated rats do not dip below pretreatment levels, although they does not increase as much in the rats treated with 3.2 mg Cyproterone acetate/kg/day as in those which received 0.2 mg Cyproterone acetate/kg/day [2]. Cyproterone acetate exhibits direct negative effect on reproductive organs weight and significant reducing effect on sperm count and Ca2+ contents. SOD and GST activities significantly decrease in addition to significant increase in NO, MDA contents reflecting the oxidative status of testis in Cyproterone acetate treated rats [3].