Physiological effects of 1,25-dihydroxyvitamin D3 in TM4 Sertoli cell line.
Physiological effects of 1,25-dihydroxyvitamin D3 in TM4 Sertoli cell line.
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1,25-二羟基维生素 D3 对 TM4 Sertoli 细胞系的生理作用。
DOI：
10.1152/ajpendo.1992.262.6.e884
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Walters,MR
中科院分区：
文献类型：
--
作者：
Akerstrom,VL;Walters,MR
1，25-二羟基维生素D3 [1，25（OH）2D 3]受体先前已在支持细胞中描述。进行本研究以评估受体在小鼠Sertoli细胞系TM 4中的生物活性。用0.01-25 nM 1，25（OH）2D 3预孵育2小时，在向细胞中加入同位素后5分钟内，45 Ca 2+的快速摄取呈剂量依赖性（27 +/-8%，n = 4次实验; P <0.05）。这种反应对1，25（OH）2D 3是特异性的，因为它不被25-羟基维生素D3、雌二醇、皮质醇、R 5020（普洛孕酮）或睾酮诱导。然而，睾酮和1，25（OH）2D 3的组合抑制了23 +/- 8%的摄取（n = 3个实验，P小于0.01）。放线菌酮抑制反应的观察结果支持了1，25（OH）2D 3刺激摄取的机制可能涉及1，25（OH）2D 3受体相互作用。相反，在与0.1-5 nM 1，25（OH）2D 3孵育24小时后，1，25（OH）2D 3处理的细胞的摄取没有可检测的变化。增加的DNA和蛋白质含量的水平也导致从2小时孵育的类固醇，并持续到24小时，没有伴随细胞数量的增加或细胞形态的可检测的变化。蔗糖梯度分析和羟基磷灰石分析证实了特异性1，25（OH）2D 3受体样结合位点的存在。这些数据表明，1，25（OH）2D 3可能通过调节受体介导的事件在睾丸功能中发挥重要作用。
1,25-Dihydroxyvitamin D3 [1,25(OH)2D3] receptors have been previously described in Sertoli cells. This study was performed to assess biological activity of the receptor in the mouse Sertoli cell line TM4. A 2-h preincubation with 0.01-25 nM 1,25(OH)2D3 resulted in a dose-dependent rapid uptake of 45Ca2+ within 5 min of addition of the isotope to the cells (27 +/- 8%, n = 4 experiments; P less than 0.05). This response was specific for 1,25(OH)2D3, in that it was not induced by 25-hydroxyvitamin D3, estradiol, cortisol, R 5020 (promegestone), or testosterone. However, a combination of testosterone and 1,25(OH)2D3 inhibited uptake by 23 +/- 8% (n = 3 experiments, P less than 0.01). That the mechanism responsible for 1,25(OH)2D3-stimulated uptake may involve 1,25(OH)2D3 receptor interaction is supported by the observation that cycloheximide inhibited the response. Conversely, there was no detectable change in uptake by 1,25(OH)2D3-treated cells after 24-h incubation with 0.1-5 nM 1,25(OH)2D3. Increased levels of DNA and protein content also resulted from a 2-h incubation with the steroid and were sustained up to 24 h without a concomitant increase in cell number or a detectable change in cell morphology. The presence of specific 1,25(OH)2D3 receptor-like binding sites was demonstrated by sucrose gradient analysis and hydroxylapatite assay. These data demonstrate that 1,25(OH)2D3 may play an important role in testicular function through regulation of receptor-mediated events.