Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile.
Adv Exp Med Biol. 2023;1428:71-82. doi: 10.1007/978-3-031-32554-0_3.
BKCa channels (large-conductance Ca-activated K channels) play a critical role in regulating vascular tone and blood pressure. These channels are present in the smooth muscle cells of blood vessels and are activated by voltage and increased intracellular Ca concentration. More recently, the expression and activity of BKCa have been proposed to be relevant in endothelial cells, too, specifically in human umbilical vein endothelial cells (HUVECs), the more studied cell type in the fetoplacental circulation. The role of BKCa in endothelial cells is not well understood, but in HUVECs or placental endothelium, these channels could be crucial for vascular tone regulation during pregnancy as part of endothelium-derived hyperpolarization (EDH), a key mechanism for an organ that lacks nervous system innervation like the placenta.In this review, we will discuss the evidence about the role of BKCa (and other Ca-activated K channels) in HUVECs and the placenta to propose a physiological mechanism for fetoplacental vascular regulation and a pathophysiological role of BKCa, mainly associated with pregnancy pathologies that present maternal hypertension and/or placental hypoxia, like preeclampsia.
BKCa 通道（大电导钙激活钾通道）在调节血管张力和血压方面起着关键作用。这些通道存在于血管的平滑肌细胞中，并通过电压和细胞内 Ca 浓度的增加而激活。最近，BKCa 的表达和活性也被认为与内皮细胞有关，特别是在人脐静脉内皮细胞（HUVEC）中，这是胎盘中循环中研究得更多的细胞类型。BKCa 在内皮细胞中的作用尚不清楚，但在 HUVEC 或胎盘内皮细胞中，这些通道可能在怀孕期间作为血管张力调节的一部分，作为内皮细胞衍生超极化（EDH）的关键机制，对于像胎盘这样缺乏神经系统支配的器官来说非常重要。在这篇综述中，我们将讨论关于 BKCa（和其他钙激活钾通道）在 HUVEC 和胎盘中的作用的证据，以提出胎盘中血管调节的生理机制和 BKCa 的病理生理作用，主要与表现出母体高血压和/或胎盘缺氧的妊娠病理有关，如子痫前期。
