草酸钙结石形成对肾组织bikunin和IαI表达的影响

Effects of renal calcium oxalate stone formation on the expressions of bikunin and IαI in kidneys

目的研究肾草酸钙结石形成对肾组织bikunin基因和间α胰蛋白酶抑制物(IαI)蛋白表达的影响,探讨bikunin在尿结石形成中的意义。方法诱导实验性大鼠肾草酸钙结石模型,收集结石大鼠、正常大鼠、临床肾结石和非结石患者每组各8例的肾组织标本。采用免疫组化、逆转录聚合酶链反应(RT-PCR)和计算机图像分析技术分别检测所有大鼠和人肾组织中bikuninmRNA和IαI蛋白的表达水平。结果正常大鼠和非结石患者肾组织均存在bikuninmRNA和IαI蛋白的表达。肾草酸钙结石形成后,结石大鼠肾组织IαI蛋白的灰度值和bikuninmRNA的相对表达水平分别为198.43±15.17、0.70±0.14;肾结石患者肾组织IαI蛋白的灰度值和bikuninmRNA的相对表达水平分别为263.25±17.41、1.27±0.13,分别和对照组相比,均显著增加(P<0.05)。结论Bikunin作为构成IαI的轻链结构,在肾草酸钙结石形成后,bikuninmRNA的表达迅速增强,提示机体通过肾脏合成更多的bikunin来抑制肾草酸钙结石的形成。

Objective To investigate the effects of the renal calcium oxalate stone formation on the expressions of bikunin gene and inter-alpha-trypsin inhibitor (I α I)protein in kidneys. Methods The formation of renal calcium oxalate stones in model rats were induced by administering ethylene glycol and ammonium chloride. All renal parenchyma tissues were harvested from all the rats and also from patients with renal calcium oxalate stones and patients without stones. Immunohistochemical assay, reverse transcription polymerase chain reaction and computer-imaging analysis techniques were used to localize and observe the expressions and changes of I α I protein and bikunin mRNA in kidneys among all patients and all rats, respectively. Results The expressions of I α I protein and bikunin mRNA were observed in the kidneys of the normal rats and non-stone patients. The density of I α I and expression level of bikunin in stone-forming rats and stone-forming patients were 198.43±15.17, 0.70±0.14 and 263.25±17.41, 1.27±0.13, respectively. The expressions were all up-regulated both in patients and rats after renal calcium oxalate stone formation. Conclusion Bikunin played an important role in urolithiasis which was the key light chain structure of I α I. Expression of bikunin mRNA was enhanced in renal calcium oxalate stone formation progress. The kidneys responded to the nephrolithic challenges by producing more bikunin that inhibited stone formation.