苯并[a]芘对大鼠学习记忆和海马氨基酸类神经递质含量的影响

目的 研究苯并a]芘(Ba]P)对大鼠学习记忆和海马氨基酸类神经递质含量的影响.方法 健康雄性SD大鼠32只,按脑室插管后的体重随机分为4组:溶剂对照组及2.5、5.0、10.0mmol/L Ba]P染毒组.以不同浓度(2.5、5.0、10.0 mmol/L)的Ba]P橄榄油溶液各10μl侧脑室注射染毒大鼠,溶剂对照组注射等体积的橄榄油.用Morris水迷宫测试大鼠的学习记忆能力.高效液相色谱一荧光检测器法测定海马氨基酸类神经递质的含量.结果 与对照组相比,Ba]P染毒组大鼠学习记忆能力明显下降,差异有统计学意义(P<0.01);而且染毒组大鼠海马谷氨酸(Gh)含量明显降低,差异有统计学意义(P<0.01);而天冬氨酸(Asp)、甘氨酸(Gly)、γ-y.氨基丁酸(GABA)含量在各组未见明显变化.结论 Ba]P能使大鼠空间学习记忆能力降低,这可能与海马兴奋性氨基酸含量的降低有关.

Influence of benzo[a]pyrene on learning and memory and content of amino acid neurotransmitters in hippocampus of rats

Objective To study the effects of benzoa]pyrene (Ba]P) on capability of learning and memory and the content of amino acid neurotransmitters in hippocampus of rats. Methods Thirty-two healthy,male SD rats were randomly divided into 4 groups according to their weights after intubated into ventricles: the solvent control group, 2.5,5.0 and 10.0 mmol/L groups. 10 μl of Ba]P olive oil solutions,of different concentrations 2.5,5.0 and 10.0 mmol/L,were injected into rats' lateral ventricles,respectively. Rats in the solvent control group were injected into the same volume of olive oil as that in Ba]P group. Rats' capability of learning and memory was tested by Morris water maze. The content of amino acid neurotransmitters in rats' hippocampuses were determined by high performance liquid chromatogram with a fluorescence detector. Results Compared with the controls, the performances of learning and memory of rats decreased significantly in Ba]P treated groups (P<0.01). Levels of glutamate (Glu) were lower significantly in treated groups than that in controls (P<0.01). No significant differences were found in contents of aspartic acid (Asp), glycine (Gly) and aminobutyric acid (GABA) among the four groups. Conclusion Ba]P can damage rats' spatial learning and memory, and which could be related to decreased contents of excitatory amino acids in hippocampus.