熊去氧胆酸对胆汁淤积幼年大鼠Mrp2和Bsep的调控作用

Regulatory Effect of UDCA on Mrp2 and Bsep of Cholestasis in Infantile Rats

目的:研究熊去氧胆酸(UDCA)对胆汁淤积幼年大鼠的治疗作用以及胆汁酸转运体多药耐药相关蛋白2(MRP2,大鼠基因表达为Mrp2)和胆盐输出泵(BSEP,大鼠基因表达为Bsep)表达的影响,探讨该药物作用的分子机制。方法:将SD幼年大鼠随机分为正常对照组(Normal组)、胆汁淤积模型组(ANIT组)和熊去氧胆酸治疗组(UDCA组)。α-萘异硫氰酸酯(ANIT)灌胃法(80 mg/kg,每周1次,共2次)诱导肝内胆汁淤积大鼠模型,分别给予安慰剂对照以及熊去氧胆酸口服(100 mg/kg,qd)治疗10 d。实验第10天处死大鼠,留取血标本进行丙氨酸氨基转移酶(ALT)、直接胆红素(DBIL)、总胆汁酸(TBA)检查,肝脏标本分别行组织病理学检查、免疫组化以及荧光定量RT-PCR检查胆汁酸转运体Mrp2和Bsep的分布以及RNA表达情况。结果:UDCA组与ANIT组比较,ALT、DBIL和TBA水平明显下降(分别为153 U/L vs 203 U/L、7 mmol/L vs 16 mmol/L、28 mmol/L vs 51 mmol/L,P<0.05),病理损害减轻,Mrp2和Bsep表达增强。结论:熊去氧胆酸能改善胆汁淤积幼年大鼠肝脏功能,减少肝细胞损害以及炎症渗出,上调胆汁酸转运体Mrp2和Bsep的表达。

Objective： To investigate the effect of ursodeoxycholic acid （UDCA） on cholestatic infantile rats and study regulation of bile acid transporter Mrp2 and Bsep, and to explore the molecule mechanism of UDCA therapy. Methods： Infantile SD rats were divided into three groups randomly. Group cholestasis was induced by alpha-naphthylisothiocyanate （ group ANIT）, and group UDCA was administered orally daily for ten days. All the rats were sacrificed on the tenth day. Blood samples were collected to detect hepatic biomarkers （ALT, DBIL, TBA） and liver samples were obtained to assay the expression of bile acid transporters Mrp2 and Bsep by immunohistochemical stains and quantitative real-time fluorescence RT-PCR. Results： Compared with group ANIT, the levels of ALT, DBIL and TBA were declined in group UDCA （ 153 U/L vs 203 U/L, 7 mmol/L vs 16 mmol/L, 28 mmol/L vs 51 mmol/L, P〈0.05 ）. Pathological damage alleviated. The expression of Mrp2 and Bsep mRNA enhanced. Conclusion： UDCA could protect the infantile rats against the ANIT induced intrahepatic cholestasis, and the hepatic protective effect involved in the up-regulation of bile acid transporter Mrp2 and Bsep.