多廿醇对高脂血症大鼠脂蛋白代谢关键酶活性的影响

目的:研究多廿醇的降胆固醇作用及其酶学机制。方法:将大鼠随机分为对照组、多廿醇(4.0mg·kg-1·d-1)预防组、多廿醇低、中、高剂量(4.0、6.0、8.0mg·kg-1·d-1)组、阳性药洛伐他汀组和高脂模型组(后5组先行高脂造模4周),灌胃给药6周后采集血液,测定血清中总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)含量;称量大鼠体质量、肝重,计算肝脏系数;测定血清卵磷脂胆固醇酰基转移酶(LCAT)、肝脏脂蛋白脂酶(LPL)和肝脂酶(HL)活性。结果:多廿醇各组能明显降低高脂模型大鼠TC39.1%～43.3%(P<0.01)、LDL-C66.6%～80.7%(P<0.01)、肝脏系数11.1%～11.8%(P<0.01);高剂量组升高HDL-C14.0%(P<0.05),中、高剂量组LCAT活性分别升高41.9%、44.3%(P<0.01),HL活性分别升高20.0%(P<0.05)、28.0%(P<0.01)。结论:多廿醇对高脂模型大鼠具有明显降胆固醇作用,其作用可能与升高脂蛋白代谢关键酶的活性有关。

Effects of Policosanol on Activity of Lipoprotein Metabolism Key Enzyme in Hyperlipoidemia Rats

OBJECTIVE： To investigate the regulation effects of policosanol on lowering cholesterol and its enzymatic mechanism. METHODS： The rats were randomly assigned into control group, policosanol prevention group （4.0 mg·kg^-1· d^-1）, policosanol low-dose, medium-dose and high-dose groups （4.0 mg·kg^-1·d^-1, 6.0 mg·kg^-1·d^-1, 8.0 mg·kg^-1·d^-1）, lovastatin group （positive control） and hyperlipoidemia model group. The last five groups were induced hyperlipoidemia model for 4 weeks. Blood samples were collected after 6 weeks administration （i.g.）. The levels of TC, TG, LDL-C and HDL-C in the serum were determined. Body weight and liver weight were measured and hepatic index was calculated. The activity of lecithin cholesterol acyl transferase （LCAT） in serum, hepatic lipoprotein lipase （LPL） and hepatic lipase （HL） were detected. RESULTS： Policosanol remarkably decreased the levels of TC （ranged from 39.1% to 43.3% ） and LDL-C （ranged from 66.6% to 80.7% ） in serum and hepatic index （ranged from 11.1% to 11.8% ） （P〈0.01）. In policosanol hig, h-dose group the levels of HDL-C in serun was increased 14.0% （P〈0.05）. In policosanol medium-dose and high-dose group, the activities of LCAT in serum were increased 41.9% and 44.3% （P〈0.01） ; the activities of HL were increased 20.0% （P〈0.05） and 28.0% （P〈0.01）. CONCLUSION： Policosanol has significant effect on reducing cholesterol, which way associate with up-regulation of the activity of lipoprotein metabolism key enzyme.