Vitamin D binding proteins.
Vitamin D binding proteins.
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维生素 D 结合蛋白。
DOI：
10.1007/978-1-4613-9934-6_2
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发表时间：
1982
影响因子：
--
通讯作者：
HaddadJr,JG
中科院分区：
文献类型：
--
作者：
HaddadJr,JG
近年来，我们对抗佝偻病甾醇的分布、代谢和作用的了解有了相当大的增长。维生素D被认为是在皮肤中合成，从肠道吸收，并转化为更有效的生物活性代谢物。无论是来自7-脱氢胆固醇的皮肤转化还是饮食来源，维生素D都进入肝脏，在肝脏中通过微粒体（De-Luca和Schnoes，1976）和/或线粒体醛（Björkhem和Holmberg，1978）羟化酶代谢为25-羟基维生素D（25-OHD）。随后，25-OHD可代谢为一系列二羟基化形式的维生素D。这些固醇中在肠和骨骼钙转运中最有效的是1，25-二羟基维生素D [1，25-（OH）2D]，它是肾细胞代谢的产物（Fraser和Kodicek，1970）。1，25-（OH）2D的产生受到密切调节，可能最显著的是受甲状旁腺激素的营养作用的调节（Fraser and Kodicek，1973）。已分离并鉴定了其他代谢物，但其生理学意义尚待澄清（DeLuca，1979）。
In recent years, considerable growth has occurred in our understanding of the distribution, metabolism, and action of antiricketic sterols. Vitamin D is recognized to be synthesized in the skin, absorbed from the intestine, and transformed to more potent bioactive metabolites. Whether derived from cutaneous transformation of 7-dehydrocholesterol or dietary sources, vitamin D enters the liver where it is metabolized to 25-hydroxyvitamin D (25-OHD) by microsomal (De-Luca and Schnoes, 1976) and/or mitrochondrial (Björkhem and Holmberg, 1978) hydroxylases. Subsequently, 25-OHD can be metabolized to an array of dihy-droxylated forms of vitamin D. The most potent of these sterols in calcium translocation at the intestine and skeleton is 1,25-dihydroxyvitamin D [1,25-(OH)2D], a product of kidney (Fraser and Kodicek, 1970) cell metabolism. The production of 1,25-(OH)2D is closely regulated, perhaps most strikingly by the trophic action of parathyroid hormone (Fraser and Kodicek, 1973). Other metabolites have been isolated arid identified, but their physiological significance awaits clarification (DeLuca, 1979).