Study Of Relationship Between The Behaviour Disfunction And The Imblance Of Intracerebrol Metal Ion Induced By Aluminum Overloading In Mice

Objects:To Explore the possible mechanism of behavioural disorders induced by overloading aluminium and protective effects of corptis totoal alkaloid in mice.Methods:1, Animal model: An aluminum overloadinging animal model was established by injecting trace amount of A1C13 into lateral ventricle of mice.2, Learning and memory test: The step-down test and programmed water maze were used to assess the changes of learning and memory functions of the experimental mice.3 , Pathomorphology: Histopathological sections were stained routinely with HE and detected the pathomorphological changes in hippocampus under the microscope.4, Other methods: Inductively coupled plasma atomic emission spectrometry, radioimmunoassay, and conventional biochemistry techniques were used to determine the levels of metal ions and ferritin, activities of MAO-B and CHE, as well as the level of serum iron.Experimental Designs:1, Investigate the time course and dosage-effect of brain aluminum overloading on the behaviours, learning and memory functions and explorethe possible mechanism of brain damage from aluminium overloading.2, Investigate whether the berberine and total alkaloid from corptis root exhibit any protective effects against the brain damage induced by aluminum overloading.Results:The latent period of step-down test was shorter and the time to search the platform in water maze test was longer in aluminium overloading mice than that of corresponding control, respectively. Histologically animals from the aluminum overloading groups exhibited various degrees of karyopyknosis and loss of neurons in the CA1 and CA3 regions. The levels of brain iron, copper, zinc, manganese were substantially higher in aluminium overloading mice than that of control. There was also a trend of elevated serum iron level, and activities of cholinesterase and monoamine oxidase B in time- and dose-dependent fashion in aluminium overloading mice. Pretreatment with 200mg/Kg body weight of total alkaloids from corptis roots significantly improved learning and memory function, decreased pathomorphological damage of hippocampi, and blunted the elevation of metal ion levels as well as activities of CHE and MAO-B from aluminium overloading mice.Conclusion:Learning and memory disfunction induced by brain aluminium overloading involves in increasing leves of iron, copper, zinc, manganese and elevating activities of cholinesterase and monoamine oxidase-B. Pretreatment of corptis total alkaloids can ameliorate the aluminium overloading-induced brain damages to certain degrees.