Immunolocalization of endothelin and neutral endopeptidase in the endometrium of users of subdermally implanted levonorgestrel (norplant®)

Abstract

Subdermally implanted slow-release levonorgestrel (Norplant®), a widely used effective contraceptive, has a high rate of discontinuation due to unacceptable menstrual bleeding disturbances. Endothelin (ET), a potent vasoconstrictor,varies across the menstrual cycle in normal endometrium.It has been proposed that ET has a potential paracrine role in the regulation of uterine blood flow.Neutral endopeptidase (NEP), a membrane-bound ectoenzyme,can inactivate ET and is localized principally in endometrial stroma. We have compared the immunolocalization of ET and NEP in endometrial biopsies from Indonesian women using Norplant® with normal controls.Differences were observed in the glandular and l..