EXPRESSION OF MESSENGER-RIBONUCLEIC-ACID FOR GONADAL-STEROID RECEPTORS IN THE HUMAN PELVIC PERITONEUM

Objective: To investigate the expression of messenger RNA (mRNA) for g onadal steroid hormone receptors in the human pelvic peritoneum. Desig n: Analysis of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR) mRNA expressions in the pelvic peritoneum was carried out using the quantitative reverse transcription-polymerase ch ain reaction (PCR) method. Setting: Department of Gynecology and Obste trics, Kyoto University Hospital, Kyoto, Japan. Patients: Pelvic perit oneal tissues from patients with (n = 10) and without (n = 10) endomet riosis who had undergone gynecological surgery were studied. Results: Estrogen receptor, PR, and AR mRNAs were detected in all pelvic perito neal samples analyzed. In the pelvic peritoneum of patients without en dometriosis, ER mRNA levels were significantly lower in the luteal pha se than in the follicular phase. This cyclic profile of ER mRNA expres sion was not observed in the pelvic peritoneum of patients with endome triosis. During the follicular phase, ER mRNA levels in the pelvic per itoneum of patients with endometriosis were significantly lower than t hose of patients with endometriosis. Neither PR nor AR mRNA levels in the pelvic peritoneum of either patient group showed significant cycli c variations throughout the menstrual cycle. A comparison of PR and AR mRNA levels in the pelvic peritoneum of the endometriosis and the non endometriosis groups revealed no significant differences. Conclusions: These data indicate a decrease in ER gene expression in the pelvic pe ritoneum of patients with endometriosis during the follicular phase. T his suggests that the possible responsiveness of peritoneal cells to e strogen may be related to the occurrence and/or development of endomet riosis.