Department of Clinical Nutrition, Shengjing Hospital, China Medical University, No. 36 Sanhao St., Heping District, Shenyang, China.
Department of Orthopedics, The Fourth Affiliated Hospital, China Medical University, No. 4 Chongshan Dong Road, Huanggu District, Shenyang, China.
Biomed Res Int. 2019 Jan 27;2019:3027036. doi: 10.1155/2019/3027036. eCollection 2019.
Vitamin D plays an important role in water and salt homeostasis. The aim of our study was to investigate the underlying relationship of Vitamin D and Aquaporins (AQP).
The behaviors of 1 (OH)-ase knockout mice and wild type mice were observed before analysis. The ICR mice were treated with vehicle or paricalcitol, a vitamin D analogue, followed by animals receiving a standard diet and free access to drinking water either with aliskiren (renin blocker; 37.5 mg aliskiren in 100 ml water), or telmisartan (a angiotensin II type I receptor blocker; 40 mg telmisartan in 100 ml water) a week before study. The expressions of AQP-1, AQP-4, and renin in mice kidneys were detected by western bolting, immunohistochemistry, and immunofluorescence.
Diuresis and polydipsia were observed in 1 (OH)-ase knockout mice, and a decreased water intake and urine output in ICR mice was observed after paricalcitol treatment. Compared with wild type, the AQP-1 expressions were increased in renal papilla and AQP-4 expressions were decreased in renal proximal tubule of 1(OH) ase knockout mice. In addition, AQP-1 was decreased in renal papilla and AQP-4 expressions were increased in proximal tubule by suppressing renin activity or supplement of Vitamin D analogue. After injecting renin into the lateral ventricle of the 1(OH)ase knockout mice, the renin expression level was decreased in the kidney, followed by the decrease of AQP-1 in renal papilla and increase of AQP-4 in proximal tubule.
Overall, Vitamin D and renin inhibitors have synergistic effects in regulating water channels in mice kidneys.
维生素 D 在水盐平衡中发挥着重要作用。本研究旨在探讨维生素 D 与水通道蛋白（AQP）之间的关系。
在分析前观察 1（OH）- 酶敲除小鼠和野生型小鼠的行为。将 ICR 小鼠用载体或帕立骨化醇（维生素 D 类似物）处理，然后用标准饮食喂养，自由饮用含雷米克林（肾素阻滞剂；100ml 水中含 37.5mg 雷米克林）或替米沙坦（血管紧张素 II 型 1 型受体阻滞剂；100ml 水中含 40mg 替米沙坦）的水一周。通过 Western 印迹、免疫组织化学和免疫荧光检测小鼠肾脏中 AQP-1、AQP-4 和肾素的表达。
1（OH）- 酶敲除小鼠出现多尿和多饮，帕立骨化醇治疗后 ICR 小鼠的饮水量和尿量减少。与野生型相比，1（OH）- 酶敲除小鼠肾脏乳头 AQP-1 表达增加，近端肾小管 AQP-4 表达减少。此外，通过抑制肾素活性或补充维生素 D 类似物，AQP-1 在肾乳头减少，AQP-4 在近端肾小管表达增加。向 1（OH）- 酶敲除小鼠侧脑室注射肾素后，肾脏中肾素表达水平降低，随后肾脏乳头 AQP-1 减少，近端肾小管 AQP-4 增加。
总体而言，维生素 D 和肾素抑制剂在调节小鼠肾脏水通道方面具有协同作用。
