长期低剂量1α，25-二羟基维生素D3对尿毒症大鼠肾脏水通道蛋白2表达的影响  

Effect of long-term low-dose 1α, 25-dihydroxy vitamin D3 on the expression of aquaporin 2 inkidneys of uremic rats

作　　者：李红芬[1] 林珊[1] 贾俊亚[1] 闫铁昆[1] 姚瑶[1] 袁鲁晓[1] 商文雅[1] 韦丽[1] 毕军[1] 

机构地区：[1]天津医科大学总医院肾内科,300052

出　　处：《中华肾脏病杂志》2013年第2期124-128,共5页Chinese Journal of Nephrology

基　　金：国家自然科学基金（30800529）;天津市卫生局重点攻关课题（1lKGl32）;天津市应用基础及前沿计划（10JCYBCll700）

摘　　要：目的观察长期低剂量1α，25-二羟基维生素D3[1，25（OH）2D3]对尿毒症模型大鼠肾脏浓缩功能及水通道蛋白（AQP）2表达的影响。方法18只SD大鼠被随机分为模型组、1，25（OH）2D3组和对照组。采用5／6肾切除方法制备大鼠尿毒症模型，1，25（OH）2D3组于术后给予1，25（OH）2D3（3ng·100g^-1·d^-1，腹腔给药），共24周。术后每4周留取大鼠血清及24h尿，检测血肌酐、精氨酸加压素（AVP）及尿蛋白量水平。24周后处死大鼠取肾行常规病理组织学检查，免疫组化及Western印迹法检测肾髓质AQP2、磷酸化（P）-AQP2表达改变，分析其与肾髓质病理改变的相关关系。结果术后24周1，25（OH）：D，组血肌酐、尿量、尿蛋白量均明显低于模型组（均P〈0．05），模型组和1，25（OH）2D3组大鼠血清AVP均显著高于对照组[（8．4±1．1）、（9．1±1．3）比（3．6±1．0）ng/L，均P〈0．01]。病理组织学检查显示1，25（OH）2D3组。肾髓质纤维化与炎细胞浸润较模型组明显减轻（P〈0．01，P〈0．05）。免疫组化结果显示，与对照组比较，1，25（OH）2D3组AQP2上调，p-AQP2在细胞顶膜的分布增加。Western印迹结果证实1，25（OH）2D3组AQP2及p-AQP2表达均显著高于模型组（均P〈0．05）。相关分析结果显示，p-AQP2表达与尿量、髓质纤维化、炎细胞浸润程度呈负相关（均P〈0．05）。结论长期低剂量1，25（OH）2D3可导致集合管AQP2及磷酸化AQP2表达增加，导致集合管对AVP的反应性增强，这可能是1，25（OH）2D3减轻尿毒症大鼠多尿症状的重要机制。Objective To investigate the effect of long- term low- dose 1α, 25- dihydroxy vitamin D3 [1,25（OH）2D3] on rat kidney aquaporin （AQP） 2 expression in 5/6 nephrectomized rats. Methods Twelve Sprague-Dawley rats underwent 5/6 nephrectomy surgery were divided into model group （n = 6） and 1,25（OH）2D3 group （n = 6） randomly; sham- operated rats only received the renal capsule stripping （control group, n = 6）. Rats in 1,25（OH）2D3 group received 1,25（OH）2D3 （3 ng. 100 g^-1·d^-1, ip） for 24 weeks. Serum and 24-hour urine specimens were collected for measurement of serum creatinine, arginine vasopressin （AVP） and urine protein. Animals were sacrificed at week 24 and kidneys were removed for routine pathological, immunohistochemistry and immunoblotting analysis.Results At week 24, plasma AVP level in 1,25（OH）2D3 and model group was much higher than that in control group （all P 〈 0.05）, with no significant differences between the former two groups （P 〉 0.05）. Lower serum ereatinine and urinary protein were presented in 1,25（OH）2D3 group compared with the model group rats at week 24 （P 〈 0.05）. Renal medullar fibrosis and inflammatory cell infiltration were improved significantly in 1,25（OH）2D3 group compared with model group （P〈0.01, P〈0.05）. Immunohistochemistry analysis revealed abundant AQP2 and p-AQP2 expressed in the renal medulla of sham group, mainly in apical membrane of collecting duct cells. AQP2 expression in model group was down- regulated （P 〈 0.05） and p- AQP2 expression in apical membrane was reduced. AQP2 expression in 1,25（OH）2D3 group increased compared with model group, with increased p- AQP2 expression in apical membrane. Western blotting revealed same results of these expressions （all P 〈 0.05）. Correlation analysis showed a negative correlation of AQP2 expression with urine volume, medullary fibrosis, and inflammatory cell infiltration （P 〈 0.05）. Conclusion Long-term low-dose 1,25（OH）2D3 improves A

关 键 词：骨化三醇 尿毒症 水通道蛋白质2 精氨酸加压素 多尿 

分 类 号：R285.5[医药卫生—中药学]