男子到了50岁左右睾酮水平开始中度下降,但70岁以上男子中只有25—30％的人睾酮水平低于正常范围。与此同时,睾酮结合蛋白水平却随年龄而增长,于是具有生物学活性的末与蛋白相结合的游离睾酮水平则显著降低。活性更强的双氢睾酮的游离部分的水平也随衰老而显著下降,但总的双氢睾酮水平降低并不明显。老年男性对人绒毛膜促性腺激素的睾酮 Men experience modest decreases in testosterone levels until about age 50, but only 25-30% of men over the age of 70 have testosterone levels below the normal range. At the same time, the level of testosterone-binding protein increases with age, so that the biologically active free-endosterone level associated with the protein is significantly reduced. The level of free portion of the more active dihydrotestosterone also decreased significantly with aging, but the overall decrease in dihydrotestosterone levels was not significant. Older male to human chorionic gonadotropin testosterone