慢性染铅对海马CA1区LTP及α-CaMKⅡ活性的抑制性影响  

THE INHIBITORY EFFECT OF CHRONIC LEAD EXPOSURE ON CA1 LTP AND ERK2 ACTIVITY IN RAT HIPPOCAMPAL AREA

作　　者：杨菁[1] 孙黎光[1] 宗志宏[1] 蔡葵[1] 王洪新[2] 

机构地区：[1]中国医科大学基础医学院生物化学教研室,辽宁沈阳110001 [2]锦州医学院分子生物学及新药开发重点实验室,辽宁锦州121004

出　　处：《中国应用生理学杂志》2006年第3期326-328,共3页Chinese Journal of Applied Physiology

基　　金：国家自然科学基金资助项目(39970651)

摘　　要：目的:探讨慢性染铅对海马CA1区长时程增强(LTP)及钙调素依赖性蛋白激酶Ⅱ(-αCaMKⅡ)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锋电位群(PS),观察对照组及不同剂量染铅组大鼠于高频刺激(HFS)前后PS幅值的变化;同时以磷酸化抗体,用Western blots方法检测海马CA1区-αCaMKⅡ活性。结果:HFS后,对照组和低、中、高剂量染铅组的幅值分别为各自的HFS前的162.5%、105.2%、86.8%、83.0%,染铅组PS幅值变化率明显低于对照组(P<0.01);以对照组-αCaMKⅡ活性为100,则低、中和高剂量染铅组活性分别为62.0±3.7、50.8±4.0、43.3±4.1,和对照组相比P<0.01,具有显著性差异。结论:慢性染铅可抑制CA1区LTP形成,而这种抑制作用可能与铅使-αCaMKⅡ活性降低密切相关。Aim： To investigate the effect of chronic lead exposure on rat hippocampal CA1 LTP and α-Ca^2＋/calmodulin-dependent protein kinase Ⅱ（α-CaM K Ⅱ ） activity in vivo. Methods： A stimulus bipolar electrode was placed on the Schaffer/Commissural fibers, with extra cellar microelectrode technique to record the population spike （PS） in the CA1 pyramidal, and we observed the changes of PS amplitude before and after the high frequency stimulation （HFS） of lower, mid and higher level lead exposure groups and the control group, respectively. The hippocarnpal CA1 α-CaM K Ⅱ activity was determined by Western blots by using phosphorylation antibody. Results： The average changes of PS after HFS of the control group, the lower, mid and higher level lead exposure groups were 162.5 %, 105.2 %, 86.8 %, 83.0 %, respectively（P 〈 0.01 vs control）. Defined control α-CaM K Ⅱ activity as 100, that the lower, mid and higher level lead exposure groups were 62.0 ± 3.7,50.8 ± 4.0,43.3 ± 4.1 （P 〈 0.01 ）. Conclusion： Chronic lead exposure can inhibit CA1 LTP in vivo , and the decrease of α-CaMK Ⅱ activity may play an important role in this mechanism.

关 键 词：铅 海马 长时程增强 钙调素依赖性蛋白激酶Ⅱ 学习记忆 

分 类 号：R995[医药卫生—毒理学]