ENDOTHELIAL NITRIC-OXIDE SYNTHASE IN THE ENDOMETRIUM DURING THE MENSTRUAL-CYCLE IN PATIENTS WITH ENDOMETRIOSIS AND ADENOMYOSIS

Objective: To determine the expression of endothelial nitric oxide syn thase in the endometrium during the menstrual cycle in endometriosis a nd adenomyosis. Design: Immunohistochemical identification of endothel ial nitric oxide in endometrial tissues using the monoclonal antibody. Setting: Department of obstetrics and gynecology in a university hosp ital. Patient(s): The subjects were divided into three groups: 35 pati ents with endometriosis, 33 patients with adenomyosis proven histologi cally, and 46 fertile controls. Main Outcome Measure(s): Semiquantitat ive immunostaining (evaluation nomogram) score in endometrial cells. R esult(s): The analyses revealed phase-dependent changes in the express ion of endothelial nitric oxide synthase in the surface and glandular epithelia during the menstrual cycle in the fertile controls. The expr ession was weakest in the early proliferative phase, gradually increas ed, was most marked in the midsecretory phase, and decreased thereafte r. In contrast, stromal cells did not change throughout the cycle. Con trary to expectations, the expression of endothelial nitric oxide synt hase in endometriosis and adenomyosis was persistently greater than th e control levels throughout the menstrual cycle. Conclusion(s): This s tudy has shown that endothelial nitric oxide synthase is changed in a phase-dependent manner during the menstrual cycle. The exaggerated exp ression of endothelial nitric oxide synthase in the endometrium throug hout the cycle suggests some pathologic role in endometriosis and aden omyosis. (C) 1998 by American Society for Reproductive Medicine.