慢性染铅对海马CA1区LTP及ERK2活性影响

目的　探讨慢性染铅对海马CA1区LTP及ERK2活性的影响。方法　用同心圆电极刺激海马的Schaffer侧支 ,于CA1区用细胞外玻璃电极记录单脉冲刺激引起的群峰电位 (PS) ,观察对照组和染铅组大鼠于高频刺激后PS幅值的变化 ;同时利用WesternBlots方法检测海马CA1区ERK2的活性。结果　HFS前记录的对照组和染铅组的PS幅值无显著性差异 ;HFS后染铅组的PS平均幅值与对照组相比下降了 79% (P <0 0 1) ;染铅组CA1区的ERK2的活性比对照组下降了 2 4 1% (P <0 0 1)。结论　慢性染铅可抑制CA1-LTP的形成 ,同时这种抑制与铅对ERK2活性抑制密切相关

Effect of chronic lead exposure on rat hippocampal CA1 LTP and ERK2 activity

ObjectiveTo investigate the effects of chronic lead expo sure on rat hippocampal CA1 LTP and Extra Cellular Signal Regulated Kinase 2 (ER K2) activity in vivo. MethodsA stimulus bipolar electrode was placed in the Sc haffer/Commissural fibers,with extra cellar microelectrode technique recorded Po pulation Spike (PS) in CA1 pyramidal,and the changes of PS amplitude was observe d before and after the high frequency stimulation (HFS) of lead exposure group a nd control,respectively.The hippocampal CA1 activity of ERK2 was determined by W estern blots. ResultsThe baseline recordings of PS evoked by single pu lse stimulation revealed no differences between control and lead exposure group. After HFS,the PS of lead exposure,on an average,decrease 79% compared with the c ontrol ( P <0.01).Lead exposure hippocgmpal CA1 ERK2 activity decreased 24.1% compared with the control ( P <0.01).ConclusionChronic lead exposure inhibited CA1 LTP in v ivo ,and the decrease of RRK2 activity may play an important role in this inhib ition.