1，25-二羟基维生素D3在小鼠肺脏液体清除中的作用

Effects of 1,25-Dihydroxyvitamin D_3 on Alveolar Fluid Clearance in Mice

目的探讨1,25-二羟基维生素D3(1,25-VD3)与在体小鼠肺泡液体清除率(AFC)之间的关系,以明确其在肺脏液体清除中的作用机制。方法维生素D处理组雄性昆明小鼠用活性维生素D类似物帕立骨化醇腹腔注射2周,应用酶标仪测定小牛血清白蛋白浓度的方法测定小鼠在体AFC。用Western blot方法测定小鼠肺组织的上皮钠通道蛋白表达水平。结果维生素D处理组小鼠AFC为(31.9±3.8)%,对照组为(19.7±1.9)%(P<0.05)。阿米洛利敏感性AFC与对照组相比增加了50%。Western blot结果显示维生素D处理组小鼠肺组织α-上皮钠通道蛋白表达水平明显提高。结论维生素D能够增加小鼠AFC,其机制可能与增加上皮钠通道蛋白表达有关。临床上应用维生素D治疗可能会有利于减轻患者的肺水肿。

Objective To explore the relationship between 1,25-dihydroxyvitamin D3 （1,25-VD3） and alveolar fluid clearance （AFC） in mice in vivo, and investigate its effects in the process of lung fluid clearance. Methods KM male mice were treated with active vitamin D analogue parieal- eitol （daily i.p. injection） for 2 weeks, and then the in vivo AFC of these mice was measured by bovine serum albumin protein assays. Westem blot was applied to determine epithelial sodium channel protein levels in lungs of these mice. Results In vivo total AFC was 31.9%＋3.8% in vitamin D- treated mice, and significantly lower in the vehicle -treated controls （ 19.7%±1.9%, P 〈 0.05 ）. Amiloride-sensitive AFC was increased approximately 50% by vitamin D. Western blot showed that the expression of a-epithelial sodium channel was significantly elevated in pariealeitol-treated mouse lungs. Conclusion These observations suggest that vitamin D augments AFC in mice, which may be related to the augment of epithelial sodium channel protein expression. The clinical application of vitamin D therapy may ameliorate ptdmonary edema of patients.