多巴胺能神经元对鱼藤酮敏感性的增龄改变及其机制  

Aging-related sensibility of dopaminergic neurons to rotenone

作　　者：曹丽丹[1] 杨亚萍[2] 郑慧芬[1] 洪雨[1] 柯国秀[1] 胡丽芳[2] 刘春风[2] 

机构地区：[1]苏州大学附属第二医院神经内科,苏州215004 [2]苏州大学神经科学研究所衰老与神经疾病实验室,苏州215123

出　　处：《中华神经医学杂志》2011年第11期1101-1105,共5页Chinese Journal of Neuromedicine

基　　金：国家自然科学基金重点项目（30930035）;省属高校自然科学研究项目（10KJB320016）

摘　　要：目的研究鱼藤酮对不同月龄SD大鼠多巴胺能神经元的影响及其机制。方法3、12、20月龄雄性SD大鼠各40只，按照随机数字表法分为自然增龄组和鱼藤酮处理组，每组20只。自然增龄组皮下注射无鱼藤酮的混合溶剂，处理组皮下注射鱼藤酮[1．0mg／（kg·d）]，连续给药30d，每周停药1d，构建大鼠鱼藤酮染毒模型。大鼠黑质切片采用酪氨酸羟化酶（TH）免疫组化染色；测定黑质组织匀浆超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性；Western blotting检测黑质部位caspase-3表达水平。结果鱼藤酮处理后各月龄大鼠TH阳性细胞计数均比相应自然增龄组降低，且20月龄大鼠降低最为明显，差异均有统计学意义（P〈0．05）。自然增龄组3月龄大鼠黑质组织SOD和CAT活性最高，20月龄大鼠有所下降，而鱼藤酮处理后各月龄大鼠SOD、CAT活性均明显增加，差异有统计学意义（P〈0．05）。Western blotting结果显示，鱼藤酮处理组各月龄大鼠剪切活化的caspase-3的表达较自然增龄组均明显增加，差异有统计学意义（P〈0．05），其中20月龄大鼠最为明显。结论鱼藤酮可诱导大鼠TH阳性细胞随年龄增加而减少，氧化应激水平的增高和caspase-3的激活可能参与了SD大鼠对鱼藤酮敏感性随年龄增加的作用机制。Objective To investigate the influence of rotenone neurotoxin on dopaminergic neurons from SD rats of different months and its mechanism. Methods Forty 3-month-old, 40 12-month-old and 40 20-month-old SD rats were chosen in our study and equally randomized into control group and rotenone treatment group, respectively （n=20）; rotenone （1.0 mg/[kg· d]） was given to the rats in the rotenone treatment group for 30 consecutive d （having drug withdrawal 1 d per week） to induce rotenone neurotoxin models. Tyrosine hydroxylase immunoreactivity in the substantia nigra pars compacta （SNpc） was observed. Levels of total superoxide dismutase （SOD） and catalase （CAT） were determined by colorimetric method and protein level of caspase-3 was determined by Western blotting. Results A significant decreased number of TH-positive cells in 3-, 12- and 20-month-old rats of rotenone treatment group was noted as compared with that in the control group, respectively （P〈0.05）, and 20-month-old rats had the fewest number. SOD and CAT activities in 3 month-old rats of the control group enjoyed the highest level and decreased trend was noted in 20 month-old rats of the control group; as compared with those in the control group, the SOD and CAT activities in all the rats of rotenone treatment group increased significantly （P〈0.05）. Western blotting revealed that the expression of cleaved caspase-3 in all the rats of rotenone treatment group obviously increased as compared with those in the control group, and 20-month-old rats showed the highest level of active caspase-3. Conclusion Rotenone can induce the decrease of TH-positive cell level following the increase of rat age; increase levels of caspase-3 and oxidative stress may take part in the mechanism of high sensibility of old SD rats to rotenone.

关 键 词：帕金森病 老化 鱼藤酮 氧化应激 半胱氨酸蛋白酶-3 

分 类 号：R742.5[医药卫生—神经病学与精神病学]