Change of steroid receptor expression in the posterior vaginal wall after local estrogen therapy

Little is known about the reaction of the posterior vaginal wall influenced by steroid receptor expression. The aim of our study was to evaluate change of estrogen and progesterone receptor expression in the posterior vaginal wall after local estrogen therapy for vaginal prolapse surgery and to compare this expression with a group of untreated women of same age. Furthermore we examined the steroid receptor expression among untreated women in each period of life. In a prospective clinical study we examined staining intensity and ratio of positive cytoblasts in specimens of vaginal tissue sampled during posterior colporrhaphy and as control group specimens from autopsied corpses to proof the change in steroid receptor expression in treated women after local estrogen therapy compared to treatment-naive women of all ages. We compared 60 premenopausal female corpses to 43 postmenopausal female corpses and 80 postmenopausal women undergoing posterior colporrhaphy to 43 postmenopasusal female corpses. Estrogen-receptor alpha score was significantly higher in the intervention group in basal epithelium (p=0.004), stroma (p≤0.001) and connective tissue (p=0.005). Estrogen-receptor beta score was significantly higher in basal epithelium (p=0.048), progesterone-receptor score was significantly higher in the intervention group in stroma and connective tissue (p≤0.001) and in superficial epithelium (p=0.017). Local vaginal estrogen therapy leads to increase in estrogen-receptor alpha and progesterone-receptor expression of the posterior vaginal wall in postmenopausal women, while estrogen-receptor-beta-expression keeps nearly unchanged. This explains the fact that proliferation of the vaginal tissue is mediated by estrogen-receptor alpha and improves the condition for our prolapse surgery.