{"paper_id":"33fdc756-1a8d-4c96-9ffe-314fb819fc7d","body_text":"Subscribe to RSS\nDOI: 10.1055/s-0036-1580648\nDivergent expression of two prostaglandin E receptors (EP1 and EP3) in normal endometrium and in ovarian endometriosis\nAuthors\nPublication History\nPublication Date:\n26 April 2016 (online)\nBackground:\nBoth the implantation and endometriosis are the results of complicated interaction of sex hormones, prostaglandins and cytokines that designate tissue to adhesion, migration and apoptosis. EP1 and EP3 have been implicated to promote these actions, respectively. Although the crucial role of prostaglandins play in diverse physiological and pathological processes is known, the possible effects of their receptors on implantation remain to be elucidated. Here we investigate the expression levels of prostaglandin receptivity in normal endometriums in comparison to that of ovarian endometriosis.\nMaterial and Methods:\nNormal endometrial tissues of 46 patients from at all phases of the menstrual cycle (n = 16 from proliferative, n = 15 from early secretory and n = 15 from late secretory) as well as ectopic endometrial tissues from 15 endometriosis patients were included and routinely processed for immunohistochemistry. The expression of EP1 and EP3 was quantified by immunohistochemical staining using a semiquantitative immunoreactive score (IRS).\nResults:\nEP1 expression of both glandular cells (P < 0.001) and stromal cells (p < 0.05) was significantly higher during the proliferative phase of the menstrual cycle than during the early secretory phase. EP3 expression of glandular cells was also significantly higher in ectopic endometrial tissues (P < 0.001). In contrast, analysis of EP3 expression revealed the exact opposite pattern: EP3 expression was significantly downregulated in glandular cells during the proliferative phase compared with the early secretory phase of the menstrual cycle (P < 0.05) and in ectopic endometrial tissues (P < 0.05). Stromal cells showed no differences in EP3 expression.\nDiscussion:\nHere, we demonstrate the divergent expression of EP1 and EP3 in endometrial tissues: While EP1 expression decreases during the window of implantation in normal endometrial tissues and increases in ectopic endometrial tissues, EP3 expression behaves in the opposite way. The mutually oppositional changes of EP1 and EP3 expression hint at a tightly orchestrated expression to facilitate implantation and might play an important role in the pathophysiology of endometriosis.","source_license":"CC0","license_restricted":false}