Slatopolsky Eduardo, Brown Alex J
Washington University School of Medicine, Renal Division, St. Louis, MO 63110, USA.
Blood Purif. 2002;20(1):109-12. doi: 10.1159/000046993.
Calcitriol controls parathyroid gland (PTG) growth and suppresses the synthesis and secretion of PTH. However, because of its potent effects on intestinal calcium and phosphorus absorption and bone mobilization, calcitriol treatment can induce hypercalcemia and hyperphosphatemia often precluding its use at therapeutic doses. In the past decade, several vitamin D analogs have been developed. These analogs retain the action on the PTG while having less effect on calcium and phosphorus. Most of these analogs for the treatment of secondary hyperparathyroidism (SH) have a modification on the side chain of calcitriol. In the USA, two vitamin D analogs 19-nor 1,25(OH)(2)D(2) and 1 alpha(OH)D(2) are currently used for the treatment of SH. Studies in animals demonstrated that 19-nor-1,25(OH)(2)D(2) is less calcemic and phosphatemic than 1 alpha(OH)D(2). The lower Ca x P product in 19-nor-1,25(OH)(2)D(2)-treated rats may be an important consideration in patient therapy. Further studies in patients are necessary to define these differences.
骨化三醇可控制甲状旁腺（PTG）的生长，并抑制甲状旁腺激素（PTH）的合成与分泌。然而，由于其对肠道钙和磷吸收以及骨动员有显著作用，骨化三醇治疗常可诱发高钙血症和高磷血症，这往往使其无法以治疗剂量使用。在过去十年中，已研发出几种维生素D类似物。这些类似物保留了对甲状旁腺的作用，而对钙和磷的影响较小。大多数用于治疗继发性甲状旁腺功能亢进（SH）的此类类似物在骨化三醇的侧链上有修饰。在美国，两种维生素D类似物19-去甲-1,25(OH)₂D₂和1α(OH)D₂目前用于治疗SH。动物研究表明，19-去甲-1,25(OH)₂D₂的血钙和血磷升高作用低于1α(OH)D₂。在接受19-去甲-1,25(OH)₂D₂治疗的大鼠中较低的钙磷乘积可能是患者治疗中的一个重要考虑因素。有必要对患者进行进一步研究以明确这些差异。
