Synthesis of 1,25-dihydroxyvitamin D in the nephrectomized pregnant rat.
Synthesis of 1,25-dihydroxyvitamin D in the nephrectomized pregnant rat.
复制标题
肾切除妊娠大鼠体内 1,25-二羟基维生素 D 的合成。
DOI：
10.1210/endo-103-6-1992
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发表时间：
1978
期刊：
影响因子：
4.8
通讯作者：
A. Root
中科院分区：
文献类型：
--
作者：
Y. Weisman;A. Vargas;G. Duckett;E. Reiter;A. Root
在妊娠第20天，将妊娠大鼠的双侧肾脏切除或假手术。随后，四组肾切除或假手术妊娠大鼠给予静脉注射[26,27- 3h]25-羟基维生素D3 ([26,27- 3h]25OHD3)，两组给予[1,2- 3h,4-14C]D3。10-24 h后处死。采用Sephadex LH-20柱层析法测定母体血浆、母体肠道、胎盘和胎儿提取物中维生素D3放射性标记代谢物的分布。维生素D3和25OHD3都通过胎盘进入胎儿体内。在接受[26,27- 3h]-25OHD3、24,25-二羟维生素D治疗的无肾动物中，在母体血浆、肠道、胎盘和胎儿的提取物中发现了1,25-二羟维生素D [1,25(OH)2D]和25,26-二羟维生素D位置的极性峰洗脱。采用高压液相色谱法对24,25-二羟基维生素D和1,25 (OH)2D进行了鉴定。在服用[1,2- 3h，4-14C]D3的大鼠中，大约50%的极性代谢物由1,25(OH)2D组成。我们得出结论，无肾妊娠大鼠能够合成1,25(OH)2D，胎儿-胎盘单元的胎儿部分是最有可能产生这种激素的部位，这种维生素D的代谢物能够通过胎盘从胎儿传递给母亲。
Pregnant rats were maintained on diets either adequate or deficient in vitamin D. On the 20th day of gestation, animals were either nephrectomized bilaterally or sham operated. Immediately therafter, four groups of nephrectomized or sham-operated pregnant rats received iv [26,27-3H]25-hydroxyvitamin D3 ([26,27-3H]25OHD3), while two groups received [1,2-3H,4-14C]D3. The animals were sacrificed 10-24 h later. The distribution of the radiolabeled metabolites of vitamin D3 was determined in extracts of maternal plasma, maternal intestinal tract, placentae, and fetuses after Sephadex LH-20 column chromatography. Both vitamin D3 and 25OHD3 crossed the placenta and entered the fetus. In anephric animals receiving [26,27-3H]-25OHD3, 24,25-dihydroxyvitamin D and a polar peak eluting in the position of 1,25-dihydroxyvitamin D [1,25(OH)2D] and 25,26-dihydroxyvitamin D were identified in extracts of maternal plasma and intestinal tracts and of placentae and fetuses. The identities of 24,25-dihydroxyvitamin D and 1,25 (OH)2D were confirmed by high pressure liquid chromatography. In rats receiving [1,2-3H,4-14C]D3, approximately 50% of the polar metabolite consisted of 1,25(OH)2D. We conclude that the anephric pregnant rat is able to synthesize 1,25(OH)2D, that the fetal portion of the feto-placental unit is the most likely site of production of this hormone, and that this metabolite of vitamin D is able to cross the placenta from the fetus to the mother.