长期硒缺乏对大鼠子代海马CA3区突触结构参数的影响  

Effects of prolonged selenium deficiency on synaptic structures in CA3 area of hippocampus in the third generation rats

作　　者：王艳[1] 苏敏[1] 田东萍[1] 

机构地区：[1]汕头大学医学院病理学教研室

出　　处：《中华病理学杂志》2005年第5期302-304,共3页Chinese Journal of Pathology

基　　金：国家自然科学基金资助项目 ( 30170832 );汕头大学发展基金资助项目

摘　　要：目的　探讨硒缺乏对生长发育期大鼠神经发育的影响及机制。方法　取子3代膳食性硒碘缺乏的生长发育期大鼠,定量研究大鼠海马CA3区GrayⅠ型突触界面结构。实验分为对照组、低硒组、低碘组、低硒低碘组,利用透射电镜观察结合图像分析,比较各组大鼠海马CA3区突触的形态结构。结果　与对照组相比,低硒组、低碘组和低硒低碘组大鼠突触活性带的长度明显缩短[分别为(261 7±50 1)nm、(286 7±41 6)nm和(220 8±61 6)nm比(312 4±47 7)nm,均P<0 01],突触后致密物质的厚度明显缩短[分别为( 22 9±6 3 )nm、( 27 5±8 6 )nm和( 25 2±6 5 )nm比(48 1±12 3)nm,均P<0 01 ],低硒组和低碘组的突触界面曲率下降( 1 076±0 039和1 079±0 038比1 108±0 054,P<0 01),低硒低碘组的突触间隙宽度明显缩小[ (11 1±3 3)nm比(16 1±4 0)nm,P<0 01]。结论　膳食性硒缺乏可能通过在突触水平发生的神经元改变,影响学习记忆等神经功能。Objective The relationship between selenium deficiency and the changes of synaptic structure in the CA3 area of hippocampus were studied in the third generation rats.Methods A selenium deficiency model was established by feeding rats with selenium-deficient food. The rats were divided into 4 groups: control (Se+I+), selenium deficiency(Se-I+), iodine deficiency(Se+I-), and both deficient group (Se-I-). The hippocampuses were dissected from the third generation rats on the 21st gestational day and the ultrastructural features of hippocampal synapses wereobserved with electron microscope. The length of active zone, synaptic curvatures, post-synaptic density (PSD) and synaptic cleft were quantitatively described.Results Compared with the control, the length of active zone and the thickness of PSD were significantly decreased in Se-I+, Se+I- and Se-I- groups [(261.7±50.1) nm、(286.7±41.6) nm and (220.8±61.6) nm contrast to (312.4±47.7) nm, P<0.01], so were the synaptic curvatures in Se-I+, Se+I- and Se-I- groups [(22.9±6.3) nm、(27.5±8.6) nm and (25.2±6.5) nm contrast to (48.1±12.3) nm,P< 0.01]; the width of synaptic cleft were also decreased significantly in Se-I- [(11.1±3.3) nm contrast to (16.1±4.0) nm,P<0.01].Conclusion Selenium deficiency might cause changes of neuronal functions at the synaptic level, and furthermore, affect learning and memory.

关 键 词：硒缺乏 大鼠 子代 海马CA3区 突触结构参数 脑发育 

分 类 号：R591[医药卫生—内科学]