{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T05:59:26Z","timestamp":1767851966801,"version":"3.49.0"},"reference-count":29,"publisher":"The Endocrine Society","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[1999,5,1]]},"abstract":"<jats:p>There is evidence from many studies indicating that a number of specific quiescent and contractile associated proteins are temporally regulated in the myometrium during pregnancy. In this present investigation we provide data that strongly suggest that myometrial connexin-43, cyclooxygenase-1 and -2 (COX-1 and -2), and Gs\u03b1 proteins are also spatially expressed within the human uterus during pregnancy and labor. Using paired lower and upper segment myometrial samples taken from individual women at term and during spontaneous labor, we have measured the expression of these proteins by immunoblotting with specific antibodies. We report that the myometrial gap junction connexin-43 protein is expressed at much greater levels in the upper uterine compared to the lower uterine segment and that this difference is even more pronounced during the course of labor. Conversely, myometrial COX-1 and -2 proteins appear to be expressed at much greater levels in the lower compared to the upper uterine segment. Moreover, the level of expression of both proteins is unaffected by the onset of parturition. In contrast, myometrial Gs\u03b1 protein appears to be uniformly expressed in both lower and upper segments and is similarly down-regulated during parturition, as previously reported. The differential expression of COX-1 and -2 and connexin-43 in the uterus may allow cervical ripening before and dilatation during labor and facilitate effective propagation of contractions from fundus to cervix, which may be further facilitated by the down-regulation of Gs\u03b1 at the onset of parturition.<\/jats:p>","DOI":"10.1210\/jcem.84.5.5644","type":"journal-article","created":{"date-parts":[[2014,1,8]],"date-time":"2014-01-08T17:04:37Z","timestamp":1389200677000},"page":"1705-1710","source":"Crossref","is-referenced-by-count":9,"title":["The Differential Expression of Myometrial Connexin-43, Cyclooxygenase-1 and -2, and Gs\u03b1 Proteins in the Upper and Lower Segments of the Human Uterus during Pregnancy and Labor1"],"prefix":"10.1210","volume":"84","author":[{"given":"Colette","family":"Sparey","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, University of Newcastle upon Tyne, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom NE1 4LP; and the Maternal and Fetal Medicine Section, Institute of Medical Genetics (F.L.), Yorkhill, Glasgow, United Kingdom G3 8SJ"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stephen C.","family":"Robson","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, University of Newcastle upon Tyne, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom NE1 4LP; and the Maternal and Fetal Medicine Section, Institute of Medical Genetics (F.L.), Yorkhill, Glasgow, United Kingdom G3 8SJ"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jarrod","family":"Bailey","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, University of Newcastle upon Tyne, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom NE1 4LP; and the Maternal and Fetal Medicine Section, Institute of Medical Genetics (F.L.), Yorkhill, Glasgow, United Kingdom G3 8SJ"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fiona","family":"Lyall","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, University of Newcastle upon Tyne, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom NE1 4LP; and the Maternal and Fetal Medicine Section, Institute of Medical Genetics (F.L.), Yorkhill, Glasgow, United Kingdom G3 8SJ"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G.","family":"Nicholas Europe-Finner","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, University of Newcastle upon Tyne, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom NE1 4LP; and the Maternal and Fetal Medicine Section, Institute of Medical Genetics (F.L.), Yorkhill, Glasgow, United Kingdom G3 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