Calcium is an essential ion in all organisms and participates in a variety of structural and functional roles. Calcium (re)absorption occurs in epithelia, including the intestine, kidney, mammary glands, placenta, and gills of fish. Its transport is regulated by a complex array of processes that are mediated by hormonal, developmental, and physiological factors involving the gastrointestinal tract, bone, kidney, and the parathyroids. Here we review the calcium transport mechanisms-paracellular, which is energy independent, and transcellular, which is energy dependent-primarily focusing on the intestine. We provide a new perspective on the facilitated diffusion and vesicular transport models to account for the emerging concepts on transcellular calcium transport. Finally, we discuss how 1,25(OH)2D3 and parathyroid hormone regulate calcium transport.

中文翻译：

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调节肠道钙的运输。

钙是所有生物中必不可少的离子，并参与多种结构和功能性作用。钙（再）吸收发生在上皮中，包括肠，肾，乳腺，胎盘和g。它的运输受到一系列复杂过程的调节，这些过程由涉及胃肠道，骨骼，肾脏和甲状旁腺的激素，发育和生理因素介导。在这里，我们回顾钙的转运机制-能量无关的旁细胞和主要依赖于肠道的能量依赖性的跨细胞。我们提供了便利的扩散和囊泡运输模型的新观点，以解释跨细胞钙运输的新兴概念。最后，我们讨论了1,25（OH）2D3和甲状旁腺激素如何调节钙的转运。