草酸钙尿结石患者肾组织中维生素K依赖羧化酶的表达及其意义

Expression and significance of vitamin K dependent gamma-glutamyl carboxylase in patients with urolithiasis

目的探讨草酸钙尿结石患者肾组织内维生素K依赖羧化酶（GGCX或VKDC）的表达及意义。方法收集肾脏皮质组织标本，其中草酸钙结石组12例，对照组23例（肾肿瘤皮质组17例，肾盂输尿管交界处狭窄和输尿管结核组6例），应用免疫组织化学法确定GGCX在组织中的定位，应用逆转录-聚合酶链反应（RT-PCR）测定各组间GGCX mRNA表达的差异，应用免疫印迹（Western blot）蛋白半定量法，对比各组GGCX蛋白的表达水平。结果GGCX定位于肾皮质肾小管上皮细胞的胞质。结石组GGCX mRNA的表达（0．0799±0．0116）明显低于对照组（0．3887±0．0732和0．3362±0．0694），差异有统计学意义（P〈0．05）。在蛋白水平上，结石组GGCX的表达（27．64±0．29）明显低于对照组（55．22±0．36和53，78±0．33），差异有统计学意义（P〈0．05）。结论草酸钙尿结石患者肾组织内GGCX表达降低在草酸钙尿结石形成中有重要作用。

Objective To study the expression of vitamin K dependent gamma-glutamyl carboxylase in patients with urolithiasis. Methods Twelve specimens of renal tissues were harvested from urolithic patients, and control tissues were harvested from renal tumor patients undergoing nephrectomy （ 17 specimens） and non-urolithic patients （6 specimens）. Immunohistochemical technique was used to study the location of GGCX in renal tissues. Reverse transcription polymerase chain reaction （RT-PCR） and Western blot techniques were used to detect the differential expression of GGCX mRNA and protein in renal tissues. Results GGCX protein located in the cytoplasm of renal tubular epithelial cells. RT-PCR revealed that the expression of GGCX mRNA in urolithie group was （0. 0799±0. 0116）, significantly lower than in the control groups [ （ 0. 3887 ± 0. 0732） and （ 0. 3362 ± 0. 0694）, respectively, P 〈 0.05 ]. The protein expression of GGCX in urolithic group [ （ 27.64 ± 0.29 ） ] was weaker than in control groups [ （ 55.22 ± 0.36） and （53.78 ± 0.33） ,respectively,P 〈0.05]. Conclusion The low expression of carboxylase in the calcium oxalate urolithie patients may play an important role in the formation of calcium oxalate urolithiasis.