苯并[a]芘对大鼠海马神经元形态学的影响  

Effects of benz[a]pyrene on hippocampus morphology of rats

作　　者：程淑群[1] 夏茵茵[1] 王应雄[1] 涂白杰[1] 

机构地区：[1]重庆医科大学公共卫生与管理学院,重庆400016

出　　处：《现代预防医学》2012年第5期1087-1088,1094,共3页Modern Preventive Medicine

基　　金：国家自然科学基金(30671744)

摘　　要：目的研究苯并[a]芘(B[a]P)对大鼠海马形态学和突触的影响。方法初断乳雄性Wistar大鼠40只,随机分为空白对照组、溶剂对照组和3个染毒组(分别为6.25、2.5和1mg/kg体重),连续腹腔染毒13周(90d)。在染毒结束后,用电镜和光镜观察海马形态学改变。结果 HE染色对照组和B[a]P暴露各组大鼠海马神经元形态结构未见明显异常,电镜仅高剂量组偶有线粒体肿胀和核浓缩现象出现。高剂量组神经元突触PSD厚度和突触活性区长度均明显小于对照组和低剂量组(P﹤0.05),突触界面半径明显大于对照组和低剂量组(P﹤0.05)。结论低剂量B[a]P暴露对海马神经元形态和超微结构无明显影响,但B[a]P可能引起突触形态学的改变,降低突触的传递效率,因而影响学习记忆能力。OBJECTIVE To study the effects of benz [ a ] pyrene on the hippocampus morphology of rats. METHODS Forty Wistar growing rats were randomly divided into five groups： blank control group, rats in solvent group were injected vegetable oil and those in experimental groups were peritoneal injected different doses of B （a） P （ lmg/kg, 2.Smg/kg, 6.25mg/kg） every day for 13 weeks. After 90 d, the hippocampus morphology of rats was observed by haematine-eos in staining and the ultrastructure of hippocampus by the transmission electron microscopy. RESULTS Results of pathological sections stained with hematoxylin and eosln showed that hippocampal neurons from all groups exhibited a typical normal appearance. Electron micro- graphs confirmed the normal appearance of hippocampal neurons, except a few swelled mitochondrias appearing in 6.25 mg/kg treatment group. Hippocampal synapse morphology was observed by transmission electron microscopy. The length of postsynaptic dlensity （PSD） and length of active zone were significantly shorter than those of control groups （P〈 0.05）, and radius of modeling circular of synaptic interface was significantly larger than those of controls （P 〈 0.05）. CONCLUSION The study suggests that low dose of B [a] P dose not impair the morphology and structure of hippocampal neuron, but B [a] P may change the hippocampal synapse morphology, further leading to impair the capability of learning and memory in rats.

关 键 词：苯并[A]芘 大鼠 海马 形态学改变 

分 类 号：R994.6[医药卫生—毒理学]