低分子肝素对子痫前期样大鼠肝脏保护作用研究

The protective action of low molecular weight heparin in liver of preeclampsia-like rats

目的研究低分子肝素（Low Molecular Weight Heparin，LMWH）对子痫前期样大鼠肝脏组织的保护作用．并从抗细胞凋亡角度探讨其可能的作用机制。方法取10只正常非孕鼠为正常非孕组，另将30只孕鼠随机分为正常孕组、子痫前期组（preeclampsiagroup，PE组）及LMWH治疗组。PE组及LMWH治疗组孕鼠均于妊娠第13天开始给予左旋硝基精氨酸甲酯（L—NAME）200mg·kg-1·d-1皮下注射，共5d．建立子痫前期样孕鼠模型。PE组于妊娠第15～20天给予生理盐水0．5ml皮下注射，LMWH治疗组于妊娠第15～20天给予LMWH40μl·kg-1·d-1皮下注射。检测各组血压、尿蛋白及ALT、AST，对LMWH疗效进行评价；采用TUNEL法检测肝脏细胞凋亡率，荧光定量PCR及WesternBlot法检测分别检测肝脏组织中caspase-3、Bcl-2及BaxmRNA和蛋白表达。结果与PE组相比，LMWH组血压及尿蛋白显著降低（P〈0．05），转氨酶J蝴及AST显著降低（P〈0．05）；LMWH组肝脏细胞凋亡率、Caspase-3mRNA及活化Caspase-3蛋白表达均显著低于PE组（P〈0．05），Bcl-2mRNA及蛋白表达显著升高，而BaxmRNA及蛋白则显著降低（P〈0．05）。结论低分子肝素可以有效改善子痫前期样大鼠肝功能，减少肝脏细胞凋亡。对其肝脏具有保护作用，这一作用可能通过调节Bcl-2／Bax平衡抑制细胞凋亡。

Objective To investigate the protective action and anti-apoptotic effect of low molecular weight heparin （LMWH） in liver of preeclampsia-like rats. Methods Thirty pregnant Wistar rats were ran- domly assigned to three groups （n = 10 for each group）： normal pregnant control group, PE group and LMWH group. Ten non-pregnant Wistar rats were treated as non-pregnant control group. In L-NAME treated group （PE and LMWH group）, L-NAME （200 mg.kg-＇.d-＇, subcutaneous injection） was used to induce preeclampsi- a-like symptoms from day 13 to 17 of gestation. LWMH（40μl·kg-1·d-1, subcutaneous injection） was given to the LMWH group from day 15 to 20, and physiological saline（0.5 ml, subcutaneous injection） was given to the PE group at the same period of time. Blood pressure, urine protein, blood transaminase levels（ ALT, AST） were measured to evaluate the curative effect of LMWH. The apoptotic index of livers was tested by TUNEL. Fluorescence quantitative PCR was used to test the content of mRNA of Caspase-3, Bcl-2 and Bax. The pro- tein expression of active caspase-3, Bcl-2 and Bax in the livers were examined by Western blot. Results The blood pressure, urine protein, and blood transaminase levels were decreased significantly in LMWH group compared with PE group（P 〈 0.05）. The apoptosis index was markedly decreased in LMWH group compared with PE group（P 〈 0.05）. In LMWH group, the mRNA level of Caspase-3 and Bax, the protein expression of active Caspase-3 and Bax were all decreased, and Bcl-2 increased significantly compared with PE group （P 〈 0.05）. Conclusions LMWH could effectively improve the liver functions in preeclampsia-like rats and markedly decrease the apoptosis in the livers. Enhanced expression of Bcl-2 and suppressed expression of Bax may be involved in the anti-apoptotic effect of LMWH.