大豆黄酮对大鼠肝脏生长代谢和相关酶活性的影响

Effects of daidzein on metabolism and related enzyme activity in isolated prefused rat liver

选用 SD大鼠 2 4只 ,体重 2 5 0± 3 0 g,随机分为对照组和两个大豆黄酮 (Da)实验组 (剂量分别为 0 .0 4mmol/L和0 .1 mmol/L)。利用大鼠离体肝脏灌流技术测定了 Da对大鼠肝脏生长代谢的影响。结果表明 Da可使大鼠离体肝脏灌流液中尿素氮浓度下降 ,并有一定的剂量效应和时间效应。在给药后灌流的 1、2、3、4h内 ,与对照组相比 ,0 .1 mmol/L的 Da使大鼠离体灌流的肝脏产生的尿素氮分别下降了 1 3 .64% (P>0 .0 5 ) ,2 3 .1 8% (P>0 .0 5 ) ,3 4.0 2 % (P<0 .0 1 )和 3 2 .91 % (P<0 .0 1 )。 0 .0 4mmol/L的 Da具有类似的效应。Da可减少大鼠肝脏葡萄糖的生成 ,0 .1 mmol/L Da使大鼠离体肝脏灌流液中葡萄糖浓度下降 1 4.3 2 % (P<0 .0 5 )。 Da还可在一定程度上抑制大鼠离体灌流的肝组织中谷丙转氨酶 (GPT)的活性。Da能使大鼠离体灌流的肝脏中 6-磷酸葡萄糖脱氢酶 (G6PDH)活性明显增加 ,0 .1 mmol/L的 Da可使大鼠肝脏中 G6PDH活性增加 45 .64% (P<0 .0 5 ) ,而 0 .0 4mmol/L的 Da对大鼠肝脏中 G6PDH活性的影响不显著。提示肝脏中的物质代谢受Da的调节 ,Da可通过增加对肝脏氮的储留 ,抑制肝脏葡萄糖的生成及增强肝脏 G6PDH活性从而继发性地影响机体的生长代谢。

Twenty four adult SD rats (250 ±30 g, BW) were used and randomly divided into three groups, a control and two treatment groups (the dose of daidzein at 0.04 mmol/L and 0.1 mmol/L , respectively). The effects of daidzein on growth metabolism were studied by the technique of isolated perfused rat liver in vitro. The results showed that urea nitrogen concentration of perfused medium was significantly affected by daidzein in a dose dependent and time-dependent manner. The urea-nitrogen level was decreased by 13.64% (P>0.05),23.18% (P>0.05),34.02% (P<0.01) and 32.91% (P<0.01) for 1h, 2h, 3h, 4h after administering daidzein at the dose of 0.1 mmol/L, respectively, compared to that of control. 0.04 mmol/L daidzein had the similar effect on urea nitrogen level. Glucose concentration of perfused medium was decreased by 14.32% (P<0.05) with daidzein treatment at the dose of 0.1 mmol/L. GTP activity of isolated perfused rat liver was inhibited by daidzein, but the difference was not significant compared with control. Meanwhile, G6PDH activity of rat liver was increased by 45.64% (P < 0.05) during daidzein treated (0.1 mmol/L), and daidzein of lower concentration (0.04 mmol/L) had not obviously effect on G6PDH activity. It is suggested that the metabolism of rat liver can be regulated by daidzein. Daidzein may improve growth metabolism by means of increasing nitrogen retention, decreasing glucose production and enhancing G6PDH activity of rat liver.