Expression of estrogen receptor isoforms α and β messenger RNA in vaginal tissue of premenopausal and postmenopausal women

Objective: To determine the messenger RNA expression patterns of estrogen receptor (ER)α and ERβ in human vaginal tissue. Study Design: Reverse transcriptase–polymerase chain reaction was performed on tissue samples of 75 patients having anterior colporrhaphy (25 premenopausal, 25 postmenopausal receiving estrogen replacement therapy [ERT], 25 postmenopausal not receiving ERT). Levels of mRNA were normalized and ratios were calculated to assess relative levels of expression. Results: All samples showed expression of the ERα isoform. Significant differences existed in ERα expression among the 3 cohorts (P = .023). Greater differences (P< .001) existed in ERβ expression. For both isoforms, the premenopausal group had the highest level, and the postmenopausal group receiving ERT had the lowest level. No significant difference in ERβ expression existed between postmenopausal groups. Conclusion: Significant differences exist between premenopausal and postmenopausal women in presence and expression of ERα and ERβ in vaginal tissue. Expression of ERβ markedly declines in menopause, regardless of ERT use. (Am J Obstet Gynecol 2001;185:1325–31.)