尿凝血酶原片断1在肾结石模型大鼠肾组织的表达及其意义

Expression of gene of urinary prothrombin fragment 1 in kidney of experimental renal calculus model in rat

目的 研究尿液中尿凝血酶原片段 1(UPTF1)的来源和UPTF1在肾结石模型大鼠肾组织的表达 ,探讨尿结石形成对肾组织UPTF1表达的影响及其在尿结石形成中的意义。方法用乙二醇和 1α 羟基维生素D3 灌胃制作大鼠肾草酸钙结石模型。采用半定量逆转录聚合酶链反应(RT PCR)检测UPTF1mRNA在结石模型大鼠和正常对照大鼠肾组织中的表达及水平变化。结果 偏光显微镜下结石模型大鼠肾乳头和肾皮质内布满草酸钙晶体 ,肾钙含量、2 4h尿草酸和尿钙分泌量分别为 13 8.3 9mg/g、82 .89μmol和97.3 5 μmol;对照组肾钙含量、2 4h尿草酸和尿钙分泌量分别为 1.5 4mg/g、2 4.2 2 μmol和3 .14 μmol,组间差异均有统计学意义(P <0 .0 1)。UPTF1mRNA在所有大鼠肾组织和肝组织中都有表达 ,但在正常大鼠和肾结石大鼠肾组织中的相对表达量分别为 1.73± 0 .2 5、1.86± 0 .19,两组差异无统计学意义意义 (P >0 .0 5 )。结论 尿液中的UPTF1来源于大鼠肾组织的生物合成 ,可能是草酸钙结石形成的生理性抑制因子 ,从而可以借助实验动物模型为研究UPTF1在尿结石形成中的作用提供了依据。

Objective To investigate the origin of urinary prothrombin fragment 1 (UPTF1) in urine and the expression of the gene of UPTF1 in kidney of experimental renal calculus model in rat and to discuss the influence of lithogenic conditions on UPTF1 gene expression as well as the potential role of UPTF1 in stone formation.Methods The rat model of renal calcium oxalate stones formation was induced by administering ethylene glycol and 1α Hydroxyvitamin D 3 [1α (OH)VitD 3] for 4 weeks.RT polymerase chain (RT PCR) reaction technique was used to detect the expression of UPTF1 mRNA in all rat kidneys and livers and the difference in the expression levels in the rat kidneys between two groups.Results The calcium oxalate crystals were found almost mainly within the papilla region or also in the tubular system and the cortical and medullar in the rat kidneys of model group under a polarized light microscope.The renal tissue calcium content,24 h urinary oxalate and urinary calcium excretion were significantly increased in the model group as compared with those in the control group (renal tissue calcium content: 138.39 mg/g vs 1.54 mg/g, P < 0.01; 24 h urinary oxalate excretion: 82.89 μmol vs 24.22 μmol, P < 0.01; 24 h urinary calcium excretion: 97.35 μmol vs 3.14 μmol, P < 0.01). The expression of UPTF1 mRNA was detectable in all rat kidneys and livers,but the difference was not significant between the model group and control group (1.73± 0.25 vs 1.86± 0.19, P > 0.05). Conclusion The origin of UPTF1 in urine was from the rat kidney biosynthesis.UPTF1 seemed to be a potential physiological inhibitor for calcium oxalate crystallization.The fact presented an opportunity for using established experimental rat model of urinary calculus to evaluate the influence of lithogenic conditions on UPTF1 gene expression and the role in stones formation.