Department of Drugs, Alcohol and Addiction, National Institute for Health and Welfare, POB 30, 00271 Helsinki, Finland.
Alcohol Alcohol. 2010 Mar-Apr;45(2):111-8. doi: 10.1093/alcalc/agp086. Epub 2010 Jan 13.
Earlier findings suggest that dopaminergic neurons are probably not critically involved in ethanol self-administration behavior and in the differential intake of ethanol by the alcohol-preferring AA (Alko Alcohol) and non-preferring ANA (Alko Non-Alcohol) rat lines selected for differential ethanol intake. The purpose of the present study was, therefore, to clarify the role of GABAergic and glutamatergic afferents and efferents with the mesolimbic dopamine system in the control of ethanol intake as well as in differential intake of ethanol by AA and ANA rats.
The effects of an acute dose of ethanol (1 or 2 g/kg i.p.) on the levels of GABA and glutamate in the ventral pallidum and the ventral tegmental area of AA and ANA rats were monitored with in vivo microdialysis. The concentrations of GABA and glutamate in the dialysates were determined with a high performance liquid chromatography system using fluorescent detection.
Ethanol significantly decreased the extracellular levels of GABA in the ventral pallidum but not in the ventral tegmental area. The ANA rats were more sensitive than the AA rats to the suppressive effect of ethanol on pallidal GABA levels. Ethanol did not have any effect on the concentrations of glutamate in either rat line.
The suppressive effect of ethanol on the extracellular levels of GABA in the ventral pallidum suggests a role for pallidal GABAergic transmission in the control of ethanol consumption.
早期研究结果表明，多巴胺能神经元可能不会在乙醇自我给药行为以及在酒精偏好 AA（Alko Alcohol）和非偏好 ANA（Alko Non-Alcohol）大鼠品系中对乙醇的差异摄入中发挥关键作用。因此，本研究的目的是阐明中脑边缘多巴胺系统的 GABA 能和谷氨酸能传入和传出对控制乙醇摄入以及 AA 和 ANA 大鼠对乙醇的差异摄入的作用。
通过体内微透析监测急性剂量乙醇（1 或 2 g/kg 腹腔注射）对 AA 和 ANA 大鼠腹侧苍白球和腹侧被盖区中 GABA 和谷氨酸水平的影响。用高效液相色谱系统和荧光检测法测定透析液中 GABA 和谷氨酸的浓度。
乙醇显著降低了腹侧苍白球中的 GABA 细胞外水平，但对腹侧被盖区没有影响。ANA 大鼠对乙醇对苍白球 GABA 水平的抑制作用比 AA 大鼠更为敏感。乙醇对两种大鼠品系的谷氨酸浓度均无影响。
乙醇对腹侧苍白球中 GABA 细胞外水平的抑制作用表明苍白球 GABA 能传递在控制乙醇消耗中起作用。
