Effect of chronic lead exposure on rathippocampal CA1 LTP and ERK2 activity

  Objective   To investigate the effects of chronic lead exposure on rathippocampal CA1LTP and Extra Cellular Signal Regulated Kinase 2(ERK 2)activityin vivo.

  Methods   A stimulus bipolar electrode was placed in the Schaffer/Commissural fibers, with extra cellar microelectrode technique recorded Population Spike(PS)in CA1 pyramidal, and the changes of PS amplitude was observed before and after the high frequency stimulation(HFS)of lead exposure group and control, respectively.The hippocampal CA1 activity of ERK 2 was determined by Western blots.

  Results   the baseline recordings of PS evoked by single pulse 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 control(P < 0.01).Lead exposure hippocgmpal CA1 ERK 2 activity decreased 24.1% compared with the control(P < 0.01).

  Conclusion   Chronic lead exposure inhibited CA1 LTP in vivo, and the decrease of RRK 2 activity may play an important role in this inhibition.