Orai1 protein expression and the role of calcium release‐activated calcium channels in the contraction of human term‐pregnant and non‐pregnant myometrium. Issue 5 (10th December 2014)

• Record Type: Journal Article
• Authors: Sutovska, Martina; Kocmalova, Michaela; Sadlonova, Vladimira; Dokus, Karol; Adamkov, Marian; Luptak, Jan; Franova, Sona
• Is Part Of: Journal of obstetrics and gynaecology research. Volume 41:Issue 5(2015:May)
• Page Start: 704
• Page End: 711
• Publication Date: 2014-12-10
• Subjects: Gynecology -- Periodicals; Obstetrics -- Periodicals; 618.1005
• DOI: 10.1111/jog.12626
• Languages: English
• ISSNs: 1341-8076

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="jog12626-sec-0001" sec-type="section"> <title>Aim</title> <p>This experimental <italic>in vitro</italic> study examined differences in the expression and activity of calcium release‐activated calcium (CRAC) channels of human term‐pregnant and non‐pregnant myometrium.</p> </sec> <sec id="jog12626-sec-0002" sec-type="section"> <title>Material and Methods</title> <p>The tissue samples were obtained from term‐pregnant myometrium in labor of women undergoing cesarean section and from non‐pregnant myometrium of women undergoing total hysterectomy due to uterine myoma. The expression of Orai1 protein, a pore‐forming subunit of CRAC channels, in human myometrium was examined using immunohistochemistry. CRAC channel involvement in the amplitude and frequency of myometrial contractions was evaluated <italic>in vitro</italic> using a tissue bath method with a CRAC ion channel blocker 3‐fluropyridine‐4‐carboxylic acid (FPCA).</p> </sec> <sec id="jog12626-sec-0003" sec-type="section"> <title>Results</title> <p>Decreased Orai1 expression was observed in human term‐pregnant laboring myometrium compared with non‐pregnant myometrium. However, the initial oxytocin‐induced contraction of myometrium was significantly suppressed at different doses of FPCA in both non‐pregnant human isolated myometrium and non‐pregnant myometrium. The frequency of contractions was the most significantly reduced at the lowest dose of FPCA in non‐pregnant myometrium and remained suppressed at all doses of FPCA in term‐pregnant myometrium. Salbutamol was shown as more effective in suppression of amplitude in term‐pregnant isolated myometrium.</p> </sec> <sec id="jog12626-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Our results provide the first information about the changes in the Orai1 protein expression and activity of human myometrial CRAC channels in term‐pregnant laboring myometrium.</p> </sec> </abstract>