The effect of estrogen and androgen on androgen receptors and mRNA levels in uterine leiomyoma, myometrium and endometrium of human subjects.

This study was designed to show the effect of estrogen and androgen on the level of testosterone and dihydrotestosterone specific binding sites (TBS and DHTBS, respectively) and to clarify the implication of androgen receptor mRNA expression to TBS and DHTBS in human uterine tissues. Estrogen mainly induces the increase of TBS and androgen receptor mRNA in uterine endometrium and leiomyoma. TBS increased by estrogen are downregulated when testosterone is given along with estrogen, while androgen receptor mRNA increased by estrogen was not significantly altered by testosterone with estrogen in endometrium and leiomyoma. These results suggest that the androgen receptor mRNA determined might encode TBS and that testosterone may stimulate the metabolic rate of TBS, or inhibit the translation rate of androgen receptor mRNA to TBS. Furthermore, the biological character of leiomyoma is considered to be an endometrial type.