慢性酒精刺激对大鼠背侧纹状体突触可塑性的影响

Effect of chronic ethanol treatment on the synaptic plasticity in dorsal striatum of rats

目的:观察较长期酒精处理及戒断后,大鼠背侧纹状体突触可塑性的变化。方法:在大鼠慢性饮酒10、20、30天及戒断后1、3、7天用脑片记录场电位的方法观察背侧纹状体长时程增强(long-term potentiation,LTP)诱导的变化,用透射电镜(TEM)观察突触超微结构的变化。结果:慢性饮酒不同时期对大鼠背侧纹状体LTP的诱导均有阻抑,饮酒10天阻抑作用最强(P<0.05),饮酒20、30天的阻抑作用逐步减弱(P>0.05),戒断7天LTP较对照组有反跳性增强(P<0.05);戒断7天突触界面活性区长度变长、饮酒20、30天组突触间隙宽度变窄、饮酒30天组和撤酒7天组突触后膜致密物质(post synaptic density,PSD)变薄(以上差异均为P<0.05)。结论:慢性酒精刺激可导致大鼠背侧纹状体突触传递效能和结合特性的改变。

Objective：To investigate the effects of chronic ethanol intake and withdrawal on the synaptic plasticity in dorsal striaturn of rats. Methods：Rats were fed with ethanol for 10,20,30d and withdrawal 1,3,7d. Extracellular recording was used to test the changes of long-term potentiation （LTP） induced in slices of dorsal striatum and transmission electron microscope （TEM） was used to observe the changes of synaptic uhrastructure. Results： Chronic ethanol exposure suppressed the induction of LTP to different extents in dorsal striaturn,with the strongest suppressive effects on LTP occurring in 10d ethanol treated rats compared with control group（P 〈 0.05）.The depression was attenuated in 20d and 30d ethanol treated rats（P 〉 0.05） and notably,LTP was potentiated in withdrawl 7d rats（P 〈 0.05）.In the synaptic uhrastructure of dorsomedial striatum, the length of synaptie active zone was longer in withdrawal 7d rats, while the width of synaptic cleft was narrower in 20d and 30d ethanol treated rats and the post synaptic density （PSD） was thinner in 30d ethanol treated rats than that of control （all above P 〈 0.05）. Conclusion：Chronic ethanol treatment may result in the changes of the efficiency of synaptic transmission and the ability of synaptic connection in rat dorsal striatum.