Unidad de Medicina Materno Fetal, División de Obstetricia y Ginecología, Pontificia Universidad Católica de Chile, Santiago, Chile.
Reprod Sci. 2013 Jan;20(1):69-77. doi: 10.1177/1933719112450335. Epub 2012 Aug 7.
We postulate that protein kinase C α (PKCα) may contribute to the maintenance of pregnancy myometrial quiescence in humans. We studied the changes in myometrial PKCα gene products (messenger RNA [mRNA] and protein) in 4 groups of women: preterm not in labor (PT-NL), preterm in labor (PT-L), term not in labor (T-NL), and term in labor (T-L). The degree of PKCα activation was studied by comparing the levels of particulate (active) PKCα with the total PKCα protein levels and by measuring PKCα activity in the cytosolic and particulate fractions. Protein kinase Cα abundance (mRNA and protein) did not increase during myometrial quiescence (PT-NL), whereas the level of PKCα activity significantly increased during quiescence. The activity of PKCα significantly decreased in the T-NL, T-L, and PT-L groups. These findings suggest that PKCα plays a significant role in the maintenance of myometrial quiescence and that PKCα activity must decrease at the end of pregnancy allowing myometrial activation. Additionally, our data demonstrate an association between reduced PKCα activity and preterm labor, which merits further investigation.
我们假设蛋白激酶 Cα（PKCα）可能有助于维持人类妊娠子宫的静止状态。我们研究了 4 组女性的子宫 PKCα 基因产物（信使 RNA[mRNA]和蛋白）的变化：早产未临产（PT-NL）、早产临产（PT-L）、足月未临产（T-NL）和足月临产（T-L）。通过比较颗粒状（活性）PKCα与总 PKCα 蛋白水平以及测量胞质和颗粒部分的 PKCα 活性，研究了 PKCα 的激活程度。在子宫静止期间（PT-NL），PKCα 的丰度（mRNA 和蛋白）并没有增加，而 PKCα 的活性在静止期间显著增加。在 T-NL、T-L 和 PT-L 组中，PKCα 的活性显著降低。这些发现表明 PKCα 在维持子宫静止中起着重要作用，并且 PKCα 的活性必须在妊娠末期降低，以允许子宫激活。此外，我们的数据表明 PKCα 活性降低与早产临产之间存在关联，值得进一步研究。
