作者：邴飞虹，程静，冯新刚，万敏，韩俊，李婧，廖一帆
【摘要】 目的观察苜蓿总皂苷提取物抗大鼠动脉粥样硬化和降血脂作用。方法该实验采用高脂饲料、血管壁钙超载、内皮损伤三者结合引发大鼠大血管动脉粥样硬化斑块模型。检测指标：用紫外分光光度计测定血清总胆固醇TCH，甘油三酯(TG)和高密度脂蛋白(HDLC)的含量;并计算低密度脂蛋白(LDLC)的含量和动脉粥样硬化指数(AI);检测主动脉的病理变化。结果苜蓿总皂苷提取物可明显降低高脂血症大鼠的血清TCH，TG，LDLC水平，明显升高HDLC水平，明显降低AI，与模型组比较有显著性差异(P< 0.05);主动脉斑块的病变分级，苜蓿总皂苷提取物明显降低粥样硬化面积，与模型组比较有显著性差异(P< 0.05)。冠状动脉病变分级，苜蓿总皂苷提取物能明显降低AS病变发生率，减轻斑块对管腔的阻塞程度。结论苜蓿总皂苷提取物具有降血脂和抗动脉粥样硬化的作用。
【关键词】 苜蓿总皂苷提取物; 大鼠; 动脉粥样硬化; 降血脂
Abstract：ObjectiveTo observe the antiatherosclerotic and hypolipidemic effects in rats of alfalfa extract of total saponins. MethodsThe atherosclerosis model in rats was set up by high fat diet in combination with blood vessel wall calcium overload and endothelial injury.Bloodfat levels(TC，TG，LDLC , HDLC and AI)in serum were measured by ultraviolet spectrophotometer.The rats were sacrificed and the aorta, heart, liver and renal were collected for pathological changes. ResultsAlfalfa extract of total saponins could significantly decrease the contents of serum TC，TG , AI and LDLC，and reduce the score of pathological changes of aorta, heart, liver and renal，while the level of HDLC was increased as compared with those of model group(P<0.05 or P<0.01). Coronary artery lesion classification, total saponins of alfalfa extract could significantly reduce the incidence of AS lesions, alleviate the degree of luminal obstruction, compared with the model group,there was significant difference.ConclusionThe results indicate that alfalfa extract of total saponins can inhibit experimental hyperlipidemia,and prevent the formation of atherosclerosis.
Key words： Total saponins of alfalfa extract; Atherosclerosis; Antiatherosclerotic
苜蓿为豆科植物紫苜蓿Medicago sativa L.或南苜蓿Medicago hispida Gaertn.的全草，是多年生草本植物。性味：苦，平，主要功能为“清脾胃、利大小肠，下膀胱结石”。《本草纲目》记载苜蓿“安中利入，可久食。利五脏、轻身健人。”民间常有“用饲牛草，嫩时人兼食之”之说。在我国中部、西部、华北广大地区，人们常摘苜蓿嫩草入菜。自古以来，苜蓿既可以作为食物入菜充饥，又可以作为药物以疗疾患。苜蓿总皂苷提取物不仅对于高脂血症有治疗作用，且由于毒性低微，还可以作为中老年人长期使用的保健品。苜蓿提取物在防治血脂代谢紊乱和抗AS方面有其独到之处[1]。一般降胆固醇制剂的作用部位在肝脏，是当胆固醇通过胃肠道吸收进入血液达到肝脏后才起作用。而苜蓿提取物降胆固醇的机理是在胃部阻止外源性胆固醇在胃肠道吸收，同时促进内源性胆固醇和胆汁的排泄，使血清磷脂浓度降低，血浆蛋白在体内分布正常，并能有效地控制血浆胆固醇和甘油三酯，从而避免了对肝脏损害的不良反应，使苜蓿提取物的开发具有更大的前景。国外对其展开研究，但是国内研究较少。本实验就苜蓿提取物作为药物在抗大鼠动脉粥样硬化和降血脂方面的作用进行研究。
