Effects of Estradiol and Testosterone on the Synthesis, Expression and Degradation of Androgen Receptor in Human Uterine Endometrial Fibroblasts.
The mechanism of known receptor-mediated androgen effects on the endometrial stroma was studied in endometrial fibroblasts derived from human uterus. 17beta-Estradiol (E) induced the expressions of androgen receptor (AR) mRNA, and predominantly increased the level of testosterone-binding sites (TBS) in uterine endometrial fibroblasts. The effect on the level of dihydrotestosterone-binding sites (DHTBS) was similar but smaller. This result suggests that the AR mRNA expressed might encode TBS, but probably not DHTBS. The TBS level increased by estrogen was down-regulated by testosterone (T) + E, but the AR mRNA expression increased by E was not down-regulated by E + T in the fibroblasts. Although the synthesis rate of AR was slightly increased (p < 0.05) by E alone or E + T, the degradation rate of AR was significantly accelerated (p < 0.05) by E + T in the fibroblasts. This result suggests that T might stimulate the metabolic rate of TBS, but does not inhibit the synthesis rate of AR mRNA to TBS in endometrial fibroblasts. Copyright 1995 S. Karger AG, Basel
Fujimoto
J.
J
Department of Obstetrics and Gynecology, Gifu University School of Medicine, Gifu, Japan.
Nishigaki
M.
M
Hori
M.
M
Ichigo
S.
S
Morishita
S.
S
Tamaya
T.
T