Effect of acetaldehyde on neurotransmitter in the rat brain

采用在体微透析技术结合高效液相色谱电化学检测器，研究了高血乙醛（AcH）浓度对自由活动大鼠纹状体和中脑核（NAc）多巴胺（DA）、5-羟色胺（5-HT）和猪毛菜醇（salsolinol）释放的影响。用顶空气相色谱法测定血中乙酰胆碱和乙醇浓度。在脑内插入探针后，仅腹腔注射氰胺（CY，25、50和100 mg/kg，一种有效的醛脱氢酶抑制剂）+ EtOH、CY+4-甲基吡唑（4-MP，82 mg/kg，一种有效的醇脱氢酶抑制剂）+ EtOH、4-MP+EtOH、CY和4-MP。仅在CY+EtOH组中观察到高血AcH浓度，并且在这些组中，在纹状体和NAc中都检测到猪毛菜醇。纹状体释放的DA，5-HT和猪毛菜醇是两倍高的NAC中的释放相比。DA和5-HT水平在所有实验组中没有显着变化，无论是在纹状体或NAc。在包括对照组（EtOH，lg/kg）在内的其他组中，在纹状体和NAc中均未观察到猪毛菜醇的形成，并且未观察到高AcH浓度。结果表明：（a）高浓度乙醛可诱导脑内猪毛菜醇的形成，（B）脑内猪毛菜醇的形成可能依赖于DA和AcH的浓度，高浓度AcH和EtOH对纹状体和NAc的DA和5-HT释放无影响。

Using in vivo microdialysis coupled with high performance liquid chromatography with an electrochemical detector, we investigated the effect of high blood acetaldehyde (AcH) concentration on the release of dopamine (DA), 5-hydroxytryptamine (5-HT) and salsolinol in the striatum and nucleus accumbens (NAc) of freely moving rats. AcH and EtOH concentrations in blood were quantified by head-space gas chromatographic method. After insertion of probe in the brain, rats were treated with cyanamide (CY, 25, 50 and 100mg/kg, a potent aldehyde dehydrogenase inhibitor) + EtOH, CY+4-methylpyrazole (4-MP, 82 mg/kg, a potent alcohol dehydrogenase inhibitor) + EtOH, 4-MP+EtOH, CY and 4-MP only intraperitoneally. High blood AcH concentration was observed only in the CY+EtOH groups, and in these groups, the salsolinol was detected both in the striatum and the NAc. The striatal release of DA, 5-HT and salsolinol was two-fold higher compared to the release in the NAc. The levels of DA and 5-HT did not change significantly in all experimental groups in either the striatum or the NAc. In the other groups including control (EtOH, lg/kg), no formation of salsolinol both in the striatum and the NAc, and no high AcH concentration was observed. With the increase in the doses of CY following EtOH, the peak concentration of salsolinon and blood AcH increased significantly.Our study indicate that (a) high acetaldehyde concentrations induce the formation of salsolinol in brain, (b) salsolinol formation in brain may can dependent on the concentration of DA and AcH, and cthere is no effect of high AcH and EtOH concentration on DA and 5-HT release both in the striatum and the NAc.