Chang L, Feng T, Li J, Dou C, Wei J, Guo Y
Institute of Urology, First Affiliated Hospital of Peking University, Beijing 100034, China.
Chin Med J (Engl). 2001 Aug;114(8):829-32.
To investigate the relationship between the expression and regulation of osteopontin (OPN) and urolithiasis.
Normal and stone model rats were treated with 1,25-dihydroxyvitamin D3(D3), vitamin K, testosterone or estradiol for 7 days, and the expression of osteopontin and its mRNA were detected with immunohistochemistry and Northern blot, respectively. Crystals deposited in rat kidneys were observed with a polarization microscope. The concentrations of crystal components in rat urine were determined.
The results showed that vitamin K, testosterone and estradiol up-regulated the expression of OPN mRNA and its protein, thus decreasing the precipitation of calcium oxalate in rat kidneys. D3 increased the concentration of calcium in urine, and accelerated the sedimentation of calcium oxalate in rat kidneys.
These findings indicate that OPN may be an important macromolecule in the normal endogenous inhibition of the formation of urolithiasis. Vitamin K, testosterone and estradiol inhibit the formation of stones via up-regulating the expression of OPN in kidneys, while D3 over dose may accelerate the process.
探讨骨桥蛋白（OPN）的表达及调控与尿路结石形成之间的关系。
用1,25 - 二羟维生素D3（D3）、维生素K、睾酮或雌二醇对正常大鼠及结石模型大鼠进行为期7天的处理，分别采用免疫组织化学法和Northern印迹法检测骨桥蛋白及其mRNA的表达。用偏光显微镜观察大鼠肾脏中沉积的晶体。测定大鼠尿液中晶体成分的浓度。
结果显示，维生素K、睾酮和雌二醇上调了OPN mRNA及其蛋白的表达，从而减少了大鼠肾脏中草酸钙的沉淀。D3增加了尿液中钙的浓度，并加速了大鼠肾脏中草酸钙的沉积。
这些研究结果表明，OPN可能是正常内源性抑制尿路结石形成的一种重要大分子物质。维生素K、睾酮和雌二醇通过上调肾脏中OPN的表达来抑制结石形成，而过量的D3可能会加速这一过程。
