外源性硫化氢对海洛因依赖大鼠海马长时程增强的影响

目的:观察外源性H2S供体NaHS对海洛因依赖大鼠学习记忆能力及海马LTP的影响。方法:SD大鼠随机分成3组:正常对照组、heroin组、heroin+NaHS组。先通过跳台实验检测大鼠学习记忆能力,然后记录高频刺激(HFS)前后在体海马CA1区群体峰电位(PS)变化,诱导长时程增强(LTP)的产生,最后通过Nissl染色观察海马神经元的损伤情况。结果:与对照组比较,heroin组和heroin+NaHS组学习记忆成绩均降低(P<0.05),PS幅值变化率减小(P<0.01),且形态学观察可见海马神经元损伤;与heroin组比较,heroin+NaHS组学习记忆成绩提高(P<0.05),PS幅值变化率增大(P<0.01),海马神经元损伤较轻。结论:(1)海洛因依赖导致大鼠海马神经元损伤,抑制海马CA1区LTP的产生,从而降低正常学习记忆能力;(2)外源性H2S可减轻海洛因依赖对大鼠海马神经元的损伤,易化海马CA1区LTP的产生,改善海洛因依赖导致的正常学习记忆能力的降低。

Effects of exogenous hydrogen sulfide on hippocampal long-term potentiation in rats with heroin dependence

Objective: To observe the effects of exogenous hydrogen sulfide on learning and memory,hippocampal long-term potentiation in rats with heroin dependence.Methods: Sprague Dawley rats were randomly divided into three groups: control group,heroin group and heroin+NaHS group.Learning and memory ability was examined by step-down test.The change of the amplitude of population spike(PS) and long-term potentiation(LTP) induction were recorded in hippocampal CA1 area before and after high frequency stimulation(HFS).The damage of hippocampal neuron was observed by Nissl staining.Results: Compared with control group,learning and memory ability reduced(P<0.05),the change of the amplitude of PS in hippocampal CA1 area was decreased(P<0.01),the damage of hippocampal neuron was observed in heroin group and heroin+NaHS group.Compared with heroin group,learning and memory ability raised(P<0.05),the change of the amplitude of PS in hippocampal CA1 area was increased(P<0.01),the damage of hippocampal neurons was alleviated in heroin+NaHS group.Conclusions:(1) Heroin dependence resulted in the damage of hippocampal neurons,inhibited LTP induction in hippocampal CA1 area,and consequently reduced the ability of learning and memory in rats;(2) Exogenous H2S reduced the damage of hippocampal neurons,facilitated LTP induction in hippocampus CA1 area,and improved learning and memory ability in heroin dependence rats.