氯化锰对大鼠纹状体和大脑皮质谷氨酸含量的影响  

Influence of manganese chloride on glutamate concentration of corpus striatum and cerebral cortex in rats

作　　者：贾克[1] 张立丰[2] 

机构地区：[1]蚌埠医学院卫生学教研室,安徽蚌埠233030 [2]中国医科大学公共卫生学院,辽宁沈阳110001

出　　处：《蚌埠医学院学报》2008年第4期389-391,共3页Journal of Bengbu Medical College

摘　　要：目的：通过观察不同剂量的锰染毒对大鼠纹状体和大脑皮质谷氨酸能神经元含量及琥珀酸脱氢酶（succ inatedehydrogenase,SDH）活性的影响,探讨锰的兴奋性毒性的作用机制。方法：大鼠按体重随机分成4组,每组10只。第1组为对照组,腹腔注射0.9%氯化钠注射液,第2～4组为锰染毒组,分别腹腔注射10、50、250μmol/kg的氯化锰,注射容量为5 m l/kg,持续染毒15天。最后一次染毒后24 h,每组取4只,将大鼠用乙醚麻醉,经左心室灌流固定后采集脑组织,用SABC免疫组织化学法测定纹状体和皮质谷氨酸能神经元含量。将每组另外6只大鼠直接处死,切取纹状体和大脑皮质,测定SDH活性。结果：大鼠腹腔单纯染锰15天后,随着剂量增加,在50μmol/kg染锰组与对照组比较,可见纹状体的阳性面积比[percentage of positive area,Aa（%）]和积分光密度（integral optical density,IOD）升高和皮质的Aa（%）升高;在250μmol/kg染锰组与对照组比较,可见纹状体和皮质的Aa（%）和IOD明显升高（P〈0.01）;在10μmol/kg染锰组与对照组比较,可见纹状体SDH活性降低（P〈0.05）;在50μmol/kg和250μmol/kg染锰组与对照组比较,SDH活性均明显降低（P〈0.01）。结论：锰可引起大鼠脑SDH活性降低和谷氨酸含量升高,谷氨酸释放到突触间隙,导致谷氨酸受体活化,诱发兴奋性毒性。Objective： To study the influence of different doses of manganese on the glutamatic neuron content and the activity of succinate dehydrogenase（SDH） in rats so as to explore the cell molecular mechanism of manganese-induced excitotoxicity. Methods： Forty Wistar rats were divided into four groups at random by weight. Group one was injected 0. 9% sodium chloride and the second to fourth groups were respectively given i. p of 10,50,250 μmol/kg MnCl2. The capacity of the injection was all 5 ml/kg. After 15 days＇ administration,the brain tissue of 4 rats in each group was removed after the rats were perfused 4% ploymerisatum from the left ventricles, and the glutamatic neuron content was determined by immunohistochemical method（SABC）. The other 6 rats in each group were executed,and the striatum and pallium were incised to determine the activity of SDH. Results： Compared with the control group, the percentage of positive area[Aa（ % ） and integral optical density（IOD）] of glutamate immunocreative cells in the striatum of the rats increased significantly,and the percentage of positive area of glutamate immunocreative cell in pallium increased significantly in 50 μmol/kg MnCl2 group;the percentage of positive area and integral optical density of glutamate immunocreative cells in striatum and pallium increased significantly in 250 μmol/kg MnCl2 group （ P 〈0.01 ） ; The activity of SDH in the striatum of the rats decreased significantly in 10 μmol/kg MnCl2 group（P 〈 0.05 ） ;The activity of SDH in the striatum and pallium of the rats decreased significantly in 50 μmol/kg and 250μmol/kg MnCl2 group （ P 〈 0.01 ）. Conclusions： Mn can decrease the activity of SDH and increase the glutamatic neuron content,which may lead to activation of glutamic acid receptor and promote excitotoxicity.

关 键 词：帕金森病 锰 谷氨酸 琥珀酸脱氢酶 纹状体 大脑皮质 大鼠 

分 类 号：R742.5[医药卫生—神经病学与精神病学] O614.711[医药卫生—临床医学]