【摘要】 目的 :探讨铅对大鼠海马神经元 Ca2 +浓度的影响及其与长时程增强 (L TP)的关系。方法 :断乳后 Wistar大鼠自由饮用不同浓度醋酸铅溶液 (0 .0 15 % ,0 .10 % ,0 .15 % ) ,建立慢性染铅动物模型。高频刺激 (HFS)海马区诱发长时程变化后 ,分离海马神经元 ,测定 [Ca2 + ]i。结果 :各染铅组大鼠海马神经元 [Ca2 + ]i与对照组比较均明显增高(P <0 .0 5 ) ;血铅浓度 (3.2 8± 0 .88) μm ol/ L 以上时海马 L TP产生率下降 ,三染铅组 PS幅值均降低 ,L TP阴性组 [Ca2 + ]i 明显高于 L TP阳性组 (P <0 .0 5 )。结论 :慢性染铅可使 HFS后大鼠海马神经元 [Ca2 + ]i 升高 ,损害海马区 L TP的在体诱导 ;铅致 L TP发生率下降与海马神经元 [Ca2 + ]i 增高有关更多还原

【Abstract】 Objective:Our aims were to study the effect of different concentration blood lead on [Ca 2+ ] i, and to figure out the relationship between [Ca 2+ ] i and long term potentiation(LTP) in rat hippocampus. Methods: Chronic lead treated animal models were acquired by feeding the male postwean Wistar rats with 0.015%,0.10%,0.15% acetate lead in drinking water for 3 months,[Ca 2+ ] i was determined after LTP of hippocampus was induced by high frequency stimulation (HFS). Results: [Ca 2+ ] i of lead treated groups was elevated significantly compared with control group; PS amplitude of lead treated groups was decreased compared with control group. The incidence of LTP reduced when the blood lead level was more than (3.28±0.88) μmol/L, [Ca 2+ ] i of LTP negative group was significantly higher than the positive one (P<0.05). Conclusion: Different concentration lead exposure can significantly increase [Ca 2+ ] i and damage the inducement of LTP in rat hippocampus after HFS; The decrease of LTP incidence leaded by lead related to the elevation of hippocampal intraneuronal [Ca 2+ ] i.更多还原