CNQX在小鼠脑不同类型突触分泌中的作用

目的:探讨6-氰基-7-硝基喹喔啉-2,3-二酮(CNQX)在小鼠脑不同类型突触分泌中的作用。方法:体外培养新生小鼠大脑皮层神经细胞与海马神经细胞,在加有不同浓度的CNQX的细胞外液中对细胞进行电生理记录,分别记录m EPSC的频率和e EPSC的幅值。结果:CNQX作用于诱发性神经递质释放的半抑制浓度(IC_(50))显著大于自发性神经递质释放的半抑制浓度,CNQX对自发性神经递质的释放作用效果更加明显。但对于不同脑区,CNQX的作用效果差异并不明显。结论:CNQX在阻断兴奋性神经递质自发释放和诱发释放时可能有不同的机制,但是并不具有脑区特异性。

The Role of CNQX in the Different Types of Synaptic Release in Mice

ABSTRACT Objective: To explore the role of 6-CYANO-2,3-DIHYDROXY-7-NITROQUIN OXALINE (CNQX) in different types of synapse secretion. Methods: The spontaneous mEPSCs and eEPSCs at different extracellular concentrations of CNQX in cul- tured cortical or hippocampal neurons were recorded respectively. Results: The half inhibitory concentration (IC50) of CNQX in evoked neurotransmitter release was significantly higher than that of spontaneous release, indicating that the spontaneous neurotransmitter release was more sensitive to CNQX. No apparent difference was observed between cortical and hippocampal cells, suggesting that the blocking effect of CNQX was similar in different brain regions. Conclusion: CNQX might have differential regulating mechanisms between excita- tory spontaneous and evoked neurotransmitter release, but without brain regions specificity.