Cyproterone acetate (Cyproterone 17-O-acetate) binds the androgen receptor (AR), thereby preventing androgen-induced receptor activation in target tissues and inhibiting the growth of testosterone-sensitive tumor cells. Cyproterone acetate is the acetate salt of a synthetic steroidal antiandrogen with weak progestational and antineoplastic activities. This agent also exerts progestational agonist properties at the level of the pituitary that reduce luteinizing hormone (LH), resulting in reductions in testicular androgen secretion and serum testosterone levels. Treatment with cyproterone alone results in incomplete suppression of serum testosterone levels.Cyproterone binds the androgen receptor (AR), thereby preventing androgen-induced receptor activation in target tissues and inhibiting the growth of testosterone-sensitive tumor cells. Cyproterone Acetate is the acetate salt of a synthetic steroidal antiandrogen with weak progestational and antineoplastic activities. This agent also exerts progestational agonist properties at the level of the pituitary that reduce luteinizing hormone (LH), resulting in reductions in testicular androgen secretion and serum testosterone levels. Treatment with cyproterone alone results in incomplete suppression of serum testosterone levels.

Androgen receptor:7.1 nM

经Cyproterone acetate处理后,大鼠体内GST和超氧化物歧化酶活性显著降低,NO明显提高,MDA含量显著增加,反映了大鼠睾丸的氧化状态.Cyproterone acetate对生殖器官重量有直接的不良作用,且会使精子数量和 Ca2+含量显著降低.秋季人为的光照时长增加以及CA处理对精子运动及形态存在负面影响. 以Cyproterone acetate处理雄激素受体后,睾丸中精细胞鱼精蛋白水平会首先下降,核染色质浓缩过程涉及的精子水平也会下降.

在睾丸激素（10 nM）存在时,低浓度Cyproterone acetate对T-刺激的3XHRE-LUC转录具有抑制作用,高浓度作用则相反。Cyproterone acetate既有明显的拮抗性能亦有部分激活剂特性,相对浓度较高时可激活AR（EC50为4.0 μM）。