REGULATION OF SEX STEROID-RECEPTOR GENE-EXPRESSION BY PROGESTERONE AND TESTOSTERONE IN CULTURED HUMAN ENDOMETRIAL STROMAL CELLS

Progesterone (P) is known to regulate sex steroid receptors in uterine cells. However, its precise regulation at the messenger ribonucleic a cid (mRNA) level is unclear. In this study we examined the effects of P and testosterone (T) on the regulation of sex steroid receptors in c ultured human endometrial stromal cells (ESC), using the quantitative reverse transcriptase polymerase chain reaction method. We isolated ES C from human endometrial tissues and cultured them with or without P ( 10(-6) mol/L) or T (10(-8) mol/L) for 9 days. Incubation with P decrea sed progesterone receptor (PR), estrogen receptor, and androgen recept or mRNA levels in cultured human ESC to 0.56 +/- 0.04-, 0.53 +/- 0.08- , and 0.84 +/- 0.04-fold (mean +/- SE), respectively. T also decreased PR, estrogen receptor, and androgen receptor mRNA levels in cultured human ESC to 0.48 +/- 0.06-, 0.52 +/- 0.05-, and 0.82 +/- 0.04-fold (m ean +/- SE), respectively. These decreases by P and T occurred in a do se-dependent manner. We also examined the sex steroid receptor levels in human ESC cultured for 0, 3, 6, and 9 days. The PR mRNA level in ES C without P was increased in a time-dependent manner. This increase wa s also inhibited by P, and the mRNA level in the presence of P was alm ost constant throughout the culture period. Our results demonstrated t hat P or T is a regulator of sex steroid receptors in ESC and that thi s regulation may influence the responsiveness to P of decidual change in ESC.