Effects of hormonal treatment on nerve fibers in endometrium and myometrium in women with endometriosis

OBJECTIVE: To investigate how hormonal treatment can change nerve fiber density and to identify types of nerve fibers in endometrium and myometrium in women with endometriosis. DESIGN: Laboratory study using human tissue. SETTING: University-based laboratory. PATIENT(S): Hormonally treated and untreated women with endometriosis undergoing hysterectomy or curettage. INTERVENTION(S): Endometrial and myometrial tissues were prepared from women with hormonally treated endometriosis and women with untreated endometriosis. MAIN OUTCOME MEASURE(S): Types and density of nerve fibers in endometrium and myometrium in women with hormonally treated and untreated endometriosis were determined immunohistochemically. RESULT(S): The nerve fiber density (mean density +/- SD per square millimeter) in the functional and the basal layers of endometrium (0.2 +/- 0.7/mm(2) and 0.9 +/- 1.3/mm(2), respectively) and myometrium (1.5 +/- 0.8/mm(2)) from women with hormonally treated endometriosis was much lower than that of endometrium (functional layer: 11 +/- 5/mm(2), basal layer: 18 +/- 8/mm(2), respectively) and myometrium (3 +/- 1/mm(2)) from women with untreated endometriosis. Nerve growth factor and nerve growth factor receptor p75 expression was also significantly reduced in women with hormonally treated endometriosis compared with women with untreated endometriosis. CONCLUSION(S): Hormonal treatment significantly reduced nerve fiber density in endometrium and myometrium in women with endometriosis.