某些药物对大鼠血浆和肝脏脂蛋白脂酶活性及血浆胆固醇的影响

高浓度极低密度脂蛋白(VLDL)和高浓度低密度脂蛋白(LDL)血症是冠心病的易患因子,脂蛋白脂酶(LPL)可使VLDL转化为LDL,故LPL可能促进动脉粥样斑块的形成。但LPL又可促进高密度脂蛋白(HDL)的生成,而HDL是防止动脉粥样硬化斑块形成的有利因子,故又认为LPL可能有利于防止斑块的生成。由此可见LPL对动脉粥样硬化的影响具有两面性,LPL在脂蛋白代谢中的作用非常复杂。

EFFEZCTS OF SOME DRUGS ON PLASMA AND LIVER LPL ACTIVITIES AND PLASMA CHOLESTEROL LEVELS IN RATS

Lipoprotein lipase (LPL) is one of the most important factors in lipoprotein metabolism. The plasma and liver LPL activities (indicaded by fatty acid release), the ratio of LPL activity to total lipase activity and theoplasma cholesterol levels in rats treated with drugs were determined so as to study the relationship between LPL and lipoprotein metabolism.Plasma LPL activity is negatively related to the total cholesterol and high density lipoprotein cholesterol levels. As the liver LPL activity, increased, the plasma LPL activity also increased. When rats were treated with insulin, phenytoin or Radix Polygonum multiflorum, the plasma and liver LPL activities and the ratio of LPL activity to total lipase activity increased, whereas the plasma total cholesterol and high density lipoprotein cholesterol levels decreased. No significant effect of phenytoin on the total cholesterol level was observed, When large doses of phenytoin were used, the plasma very low density lipoprotein and low density lipoprotein cholesterol level increased and the ratio of high density lipoprotein cholesterol to total cholesterol decreased.