补肾活血和泻下方药及其配伍对老龄大鼠脑缺血自由基损伤的影响

Effect of drugs for tonifying the kidney and promoting blood circulation,purgation and both of compatibility in aged rats with cerebral ischemia on free radical

目的 :从自由基损伤方面研究老年大鼠脑缺血的发病机制和中药的防治作用。方法 :青年大鼠分为青年对照组、青年模型组 ;老龄大鼠分为老龄对照组、老龄模型组、尼莫地平组、大黄组、益元活血组及益元活血大黄组。观察脑缺血模型大鼠脑电图幅值、脑含水量、超氧化物歧化酶 (SOD)、丙二醛 (MDA)和一氧化氮 (NO)含量的变化。结果 :1青年和老龄模型组脑电图幅值以及血清与脑组织 SOD活性分别较青年和老龄对照组降低(P<0 .0 5或 P<0 .0 1) ,而脑含水量、MDA和 NO含量增高 (P<0 .0 5或 P<0 .0 1)。 2与青年模型组比较 ,老龄模型组脑电图幅值以及血清与脑组织 SOD活性降低 ,脑含水量、脑组织 MDA及血清 NO含量增高(P<0 .0 5或 P<0 .0 1)。 3与老龄模型组比较 ,用药各组脑电图幅值以及血清 SOD活性提高 (P均 <0 .0 1) ,脑含水量、脑组织 MDA含量下降 (P均 <0 .0 5 )。大黄组血清和脑组织 NO水平降低 (P均 <0 .0 1)。结论 :青年和老龄大鼠脑缺血损伤与自由基损伤有关 ,老龄大鼠较青年大鼠严重 ,其机制与增龄有一定的关系。补肾活血方药和泻下方药及其配伍通过拮抗自由基损伤、改善 NO代谢而对老龄大鼠脑缺血损伤有一定的保护作用。

Objective:To study pathogenesis of ischemic brain damage in aged rats by free radical and the effect of prevention and cure of the traditional Chinese medicine.Methods:Young rats were randomly divided into young control group and young model group;aged rats were randomly divided into aged control group,aged model group,Nimodipine group,rhubard(大黄) group,Yiyuanhuoxue(益元活血丹) group and Yiyuanhuoxuedahuang (益元活血丹合用大黄) group.The changes of the wave amplitude of electroencephalogram (EEG),the brain water ratio,the contents of superoxide dismutase(SOD),malondialdehyde(MDA) and nitric oxide(NO) were observed in the rats with incomplete cerebral ischemia.Results:①There were more significance between young model group and young control one,the same as between aged model group and aged control one in decreasing the wave amplitude of EEG and serum and brain tissue SOD activity( P <0 01, P <0 05),and increasing the brain water ratio,serum and brain tissue ones of MDA and NO ( P <0 05, P <0 01).②The wave amplitude of EEG and serum and brain tissue SOD activity were decreased, while the brain water ratio,brain tissue MDA contents and serum NO contents were elevated in aged model group with respect to young model one( P <0 05, P <0 01).③Compared with aged model group,the wave amplitude of EEG and serum levels of SOD in all treated group were higher(both P <0 01),while the brain water ratio, brain tissue MDA contents decreased(both P <0 01).Serum and brain tissue contents of NO decreased in rhubard group(both P <0 01).Conclusion:The mechanism that ischemic brain damage is more serious in aged rats than that in young's is related to aging.Drugs for tonifying the kidney and promoting blood circulation and purgation and compatibility have protective effects on cerebral ischemia in aged rats by antagonising the damage of free radical and improving metabolism of NO.