摘要
目的:研究左旋精氨酸(L-Arg)对大鼠动脉粥样硬化斑块及一氧化氮合酶(NOS)的影响。方法:将40只W istar大鼠分为正常对照、高脂血症、动脉粥样硬化及L-Arg 4组,每组10只。除正常对照组外,3组大鼠均予高脂饲料;动脉硬化组辅以维生素D3治疗,L-Arg组在饮水中另加入L-Arg治疗。所有大鼠在实验后7天行手术,90天后观察主动脉粥样斑块形成及NOS的活性,采用高效液相色谱(HPLC)检测血清L-Arg水平。结果:①高脂血症组、动脉粥样硬化组和L-Arg组血清总胆固醇、甘油三酯和低密度脂蛋白均明显增高(P<0.01),而高密度脂蛋白均明显下降(P<0.01)。上述4项指标在高脂血症组与动脉粥样硬化组之间均无显著差异(P>0.05)。②高脂血症组和动脉粥样硬化组血清L-Arg均无影响,补充L-Arg可使其明显增高(P<0.01,VS其余3组)。③胸主动脉HE染色,动脉粥样硬化组动脉形成明显的具有脂质聚集、炎性细胞聚集、钙化等特点的斑块,高脂血症组动脉结构未见明显的改变;L-Arg组动脉管壁有小的钙化和斑块,较动脉粥样硬化组减轻。④胸主动脉诱导型NOS(iNOS)免疫组织化学检测,正常对照组和高脂血症组均为阴性;动脉粥样硬化组为强阳性;L-Arg组为阳性。⑤血管中内皮型NOS(eNOS)活性高脂血症组、动脉粥样硬化组及L-Arg组较正常对照组均下降(P<0.01),与动脉粥样硬化组比较,L-Arg组有一定的恢复(P<0.05);iNOS活性高脂血症组较正常对照组无差异(P>0.05),而动脉粥样硬化组及L-Arg组均显著增加(P<0.01)。⑥高脂血症组和动脉粥样硬化组血清L-Arg浓度与正常对照组比较无显著差异(P>0.05),而L-Arg组血清L-Arg浓度与其他3组比较显著增高(P<0.01)。结论:补充L-Arg增加了内皮功能,使动脉粥样硬化的发展减轻,但由于其对iNOS无作用,动脉仍形成斑块。
Objective：To observe the effects and mechanisms of L-Arginine（L-Arg） on atherosclerosis plaques in rats. Methods： 40 Wistar rats were divided into 4 groups：the normal group,the hyperlipidemia group,the atherosclerosls group and the L-Arg group, in each of which there were 10 rats. Except for the rats in the normal group,all the rats in the other group were fat with high fed diet. But the A-group was supplemented with vitamin D3 and the L-Arg was added into the L-Arg＇s drinking water. All the rats were operated on 7days after the experiment and 90 days after the operations the formation of atherosclerosis plagues and the activities of nitric oxide synthuse （NOS） were studied and tested by HPLC. Results： ①There was an obvious increase in serum TC,TG and LDLC in the hyperlipidemia, atherosclerosis and L-Arg groups （P 〈 0. 01 ） , but HDLC decreased significantly （P 〈 0. 01 ）. There was no difference in the above 4 indexes between the H-group and the A-group. ② Serum L-Arginine in the H-group and A-group was same,but there was an significant increase in the serum when added with L-Arg （P 〈 0.01 VS the other three groups）. ③Thoracic aorta HE staining：distinct plaques with abundant lipids,inflammatory cells aggregation and calcification formed in thoracic aortas of atheroslerosis group ; structure of aortas in hyperlipidcmia group was normal; there were small plaques and calcification in L Arginine group. There was no obvious change in the structure of aortas in the H-group,but there were small formations of plagues and calcification on the walls of aortas in the L-Arg group but smaller than that of the A-group. ④ The immunohistochemical test of thoracic aorta NOS （iNOS） showed that the control group and the H-group turned out to be negative while the A-group and L-Arg group highly positive. ⑤Aetivities of NOS （eNOS） in blood vessels were at a lower level in the H-group,A-group and L-Arg group than that of the N-group （P 〈 0. 01 ） , hut there was a certain amount of recovery in the L-Arg group （P 〈 0.05 ）. The expressions and activities of iNOS showed no difference between the H-group and the N-group（ P 〉 0. 05 ） ,while the A-group showed an obivous increase（ P 〈 0. 01 ）. ⑥ There was no obvious difference in the serum L-Arg between that of the H and A-groups and that of the N-group（P 〉 0. 05 ） ,but the density of the serum L-Arg in the L-Arg group was obviously higher than that of the three other groups（ P 〈 0. 01 ）. Conclusion：L-Arg can improve endothelial functions and alleviate development of formation of athcrosclerosis but plagues form because it has no effect on iNOS.
出处
《华北国防医药》
2006年第6期381-384,F0003,共5页
Medical Journal of Beijing Military Region
