Involvement of non-exocytotic mechanisms in ethanol-induced in vivo dopamine release: comparisons with cocaine.
Involvement of non-exocytotic mechanisms in ethanol-induced in vivo dopamine release: comparisons with cocaine.
复制标题
非胞吐机制参与乙醇诱导的体内多巴胺释放：与可卡因的比较。
DOI：
10.1016/j.ejphar.2003.08.008
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发表时间：
2003
影响因子：
5
通讯作者：
Yan,Qing-Shan
中科院分区：
文献类型：
--
作者：
Yan,Qing-Shan
为了确定是否参与乙醇诱导的体内多巴胺释放在延髓核的非胞吐机制，细胞外多巴胺浓度测定通过脑内微透析在自由移动的Sprague-Dawley大鼠。乙醇对多巴胺释放的影响在脑桥核进行了比较与可卡因，一种药物，增加突触多巴胺的机制，这取决于神经元的活动，并涉及胞吐过程。通过透析探针给予乙醇（80 mM）或可卡因（10 μM）可增加延髓核中细胞外多巴胺的浓度。用河豚毒素（2 μM）或Ca 2+戒断预处理不能阻断乙醇增加丘脑核多巴胺的能力。通过局部输注舒必利阻断多巴胺自身受体也没有显著改变乙醇对丘脑核多巴胺的作用。然而，与乙醇相反，可卡因诱导的伏隔核多巴胺增加对河豚毒素或Ca 2+缺失敏感。此外，舒必利预处理显着增强可卡因对细胞外多巴胺浓度的影响。河豚毒素，Ca 2+撤退和多巴胺自身受体的抑制反应的这些差异表明，非胞吐机制可能参与多巴胺释放引起的局部应用乙醇在延髓核。
In order to determine whether a non-exocytotic mechanism was involved in ethanol-induced in vivo dopamine release in the nucleus accumbens, extracellular dopamine concentrations were measured via intracerebral microdialysis in freely moving Sprague–Dawley rats. Effects of ethanol on dopamine release in the nucleus accumbens were compared with those by cocaine, a drug that increases synaptic dopamine by a mechanism, which depends on neuronal activity and involves an exocytotic process. Administration of ethanol (80 mM) or cocaine (10 μM) via a dialysis probe increased extracellular dopamine concentrations in the nucleus accumbens. Pretreatments with tetrodotoxin (2 μM) or Ca2+withdrawal did not block the ability of ethanol to increase nucleus accumbens dopamine. The blockade of dopamine autoreceptors by local infusion of sulpiride did not significantly alter the effect of ethanol on nucleus accumbens dopamine either. As opposed to ethanol, however, cocaine-induced increases in nucleus accumbens dopamine were sensitive to tetrodotoxin or Ca2+omission. In addition, pretreatments with sulpiride significantly potentiated the effect of cocaine on extracellular dopamine concentrations. These differences in responses to tetrodotoxin, Ca2+withdrawal and inhibition of dopamine autoreceptors suggest that a non-exocytotic mechanism may be involved in dopamine release in the nucleus accumbens evoked by focally applied ethanol.