银杏叶提取物对实验性高脂血症大鼠的调脂机制

目的 研究银杏叶提取物对实验性高脂血症大鼠的调脂机制.方法 预防给药,即以高脂饲料造模的同时连续给药28 d,于末次给药后测定大鼠血浆中总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)的含量和脂蛋白脂酶(LPL)、肝脂酶(HL)的活性及大鼠粪便中胆汁酸(FBA)的排泄量;治疗给药,即给予高脂饲料喂养28 d,造模成功后连续给药28 d,测定大鼠血浆中TC、TG、HDL-C、LDL-C的含量和LPL、HL的活性及大鼠FBA的排泄量.结果 预防性给药后,银杏叶提取物高、中剂量组与高脂模型组比较,能显著降低血浆中TC、LDL-C,显著升高HDL-C,同时可显著提高HL和LPL的活性及增加大鼠FBA的排泄量;治疗性给药后,银杏叶提取物高、中剂量组与高脂模型组比较,能显著降低已形成高脂血症大鼠血浆中的TC、LDL-C,显著升高HDL-C,同时可显著提高HL、LPL的活性及增加大鼠FBA的排泄量.结论 银杏叶提取物对大鼠实验性高脂血症具有显著的预防和治疗作用.其作用机制可能与药物提高LPL和HL的活性并加速体内胆固醇的代谢有关.

Mechanism of Ginkgo biloba extracts in regulating blood-lipid on experimental hyperlipidemic rats

OBJECTIVE To study the possible mechanism of Ginkgo biloba extracts(GBE) in regulating blood-liqid.METHODS The rats were raised with high fat diet for 4 weeks and co-administered with three doses of GBE.Then the concentration of TC,TG,HDL-C,LDL-C,lipoprotein lipase(LPL),hepatic lipase(HL) in plasma and fecal bile acid were assayed.In the therapeutic study,the rats hyperlipidemia model were formed by feeding with high lipid diet for 4 weeks,and then treated with three doses of GBE.After 4 weeks,the levels of TC,TG,HDL-C,LDL-C,LPL,HL in plasma and fecal bile acid were determined.RESULTS In the prevention study,GBE of the middle and high dose markedly decreased the concentration of TC,TG,LDL-C in plasma and fecal bile acid.Meanwhile,it significantly increased the levels of HDL-C and the activities of HL and LPL.In the therapeutic study,GBE of high dose significantly reduced the concentrations of TC,TG,LDL-C in plasma and fecal bile acid.And significant increases in LPL and HL activity were noted in the administered group,especially Ginkgo biloba of high dose.CONCLUSION GBE could significantly prevent hyperlipidemia and decrease the occurrence of hyperlipidemia.Meanwhile,it could increase the levels of LPL and HL activities,and accelerate TC metabolism by increasing the fecal bile acid,which may be one of the main mechanism of GBE effect on regulating blood liqid.