人参皂苷Rb1对染铅小鼠骨铅含量及行为记忆的影响

目的：研究人参皂苷Rb1对染铅小鼠骨铅含量、学习记忆功能的影响及其对脑内超氧化物歧化酶(SOD)活性和一氧化氮合酶（NOS）活性的影响。方法：以醋酸铅饮水制备染铅小鼠模型，分为空白对照组、模型组、人参皂苷Rb1（100、50和25 mg·kg^-1）组，采用避暗实验及Morris水迷宫实验评价人参皂苷Rb1对学习记忆的影响，并测定小鼠的骨铅含量、脑组织中SOD活性和NOS活性。结果：与空白对照组比较，模型组小鼠避暗实验潜伏期缩短（P<0.01）、错误次数增加（P<0.05）；水迷宫实验，与空白组比较，模型组搜索路程及潜伏期均延长（P<0.05）； SOD活性降低，NOS活性升高，骨铅含量升高（P<0.01）。与模型组比较，人参皂苷Rb1组小鼠避暗实验潜伏期延长、错误次数减少；水迷宫实验与模型组比较搜索路程及潜伏期均缩短（P<0.05或P<0.01）；SOD活性升高（P<0.05或P<0.01）；NOS活性降低（P<0.05或P<0.01），骨铅含量降低（P<0.01），以上作用均呈现剂量依赖性。其中，25 mg·kg^-1剂量组与100和50 mg·kg^-1剂量组之间存在显著性差异（P<0.05）。结论：人参皂苷Rb1可减少铅在骨组织中的沉积，对染铅小鼠的学习记忆障碍有改善作用，可提高染铅小鼠体内的抗氧化系统活力。

Effects of ginsenoside Rb_1 on content of lead in bone and learning and memory in mice exposure to lead

Objective To discuss the effects of ginsenoside Rb1 on bone lead content,learning and memory,the activities of superoxide dismutase(SOD) and nitric oxide synthase(NOS) in brain of mice exposure to lead.Methods The lead-exposed models of mice were induced by lead acetate contained in drinking water.The mice were divided into control group,model group and different doses of ginsenoside Rb1 groups(100,50,25 mg·kg-1).Passive avoidance experiment and Morris water maze test were used to evaluate the effects of ginsenoside Rb1 on learning and memory of lead mice,and to determine the bone lead content,the activities of SOD and NOS in brain.Results Compared with control group,lead-exposuring could lead the following results: shortening the incubation period of avoid dark experiment(P<0.01),increasing the number of errors(P<0.05),extending the search distance and the incubation period in Morris water maze test(P<0.05),reducing the activity of SOD,increasing the activity of NOS and the bone lead content(P<0.01).Compared with model group,the incubation period of passive avoidance experiment was obviously extended,the number of errors was clearly reduced,the search distance and the incubation period in ginsenoside Rb1 groups were apparently shortened(P<0.05 or P<0.01),the activity of SOD was increased(P<0.05 or P<0.01),the activity of NOS and the bone lead content were decreased(P<0.05 or P<0.01.All the effects were dosage-dependent.And the effect of 25 mg·kg-1 ginsenoside Rb1 was significantly different compared with 100 and 50 mg·kg-1 ginsenoside Rb1(P<0.05).Conclusion Ginsenoside Rb1 can reduce the lead content significantly,and obviously alleviate learning and memory of lead mice.It could meanwhile effectively resume the vitality of the antioxidant system of lead mice and protect their nerve cells.