Bragulat Veronique, Dzemidzic Mario, Talavage Thomas, Davidson Dena, O'Connor Sean J, Kareken David A
Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
Alcohol Clin Exp Res. 2008 Jul;32(7):1124-34. doi: 10.1111/j.1530-0277.2008.00693.x.
Small, priming doses of alcohol enhance desire to drink, and thus play a role in the loss of control of alcohol consumption. Using functional magnetic resonance imaging (fMRI), we previously showed that alcoholic drink odors (AO; subjects' drinks of choice) induce greater nucleus accumbens (NAc) activity than non-appetitive odors (NApO; grass, leather) in subjects at risk for alcoholism. Here we hypothesized that priming exposure to alcohol would enhance responses to AO in the NAc and orbitofrontal cortex in comparison to NApO (grass, leather) and to the appetitive control odors (ApCO) of chocolate and grape.
Ten hazardous drinkers (mean age = 22.7; SD = 2.9, average drinks per drinking day = 5.9, SD = 2.3; drinking days/90 days = 50.4, SD = 13.7) were scanned on a 1.5 T GE Signa MR scanner during intravenous infusion of lactated Ringer's or 6% ethanol in lactated Ringer's that was pharmacokinetically modeled to achieve a constant breath alcohol concentration (BrAC) of 50 mg% throughout imaging. During scanning, subjects sniffed AO, NApO, and ApCO.
Alcohol infusion enhanced the contrast between AO and NApO in the NAc, and in orbitofrontal, medial frontal, and precuneus/posterior cingulate regions. The contrast between AO and appetitive control odors (ApCO; chocolate and grape) was similarly larger in the orbital, medial frontal, precuneus, and posterior cingulate/retrosplenial areas, with the most robust finding being a potentiated response in the posterior cingulate/retrosplenial area. The orbital region is similar to an area previously shown to manifest satiety-related decreases in activity induced by food cues.
The results suggest that priming exposure to alcohol renders a limbic network more responsive to alcohol cues, potentially enhancing desire to drink.
少量的起始剂量酒精会增强饮酒欲望，从而在饮酒失去控制方面起作用。我们之前使用功能磁共振成像（fMRI）表明，对于有酒精成瘾风险的受试者，酒精饮料气味（AO；受试者的首选饮品）比非刺激性气味（NApO；草、皮革）能诱发更大的伏隔核（NAc）活动。在此，我们假设与NApO（草、皮革）以及巧克力和葡萄的刺激性对照气味（ApCO）相比，起始接触酒精会增强NAc和眶额皮质对AO的反应。
对10名危险饮酒者（平均年龄 = 22.7岁；标准差 = 2.9，平均每日饮酒量 = 5.9杯，标准差 = 2.3；90天内饮酒天数 = 50.4天，标准差 = 13.7）在1.5T的GE Signa MR扫描仪上进行扫描，期间静脉输注乳酸林格氏液或含6%乙醇的乳酸林格氏液，通过药代动力学模型使其在整个成像过程中达到恒定的呼气酒精浓度（BrAC）50mg%。在扫描过程中，受试者嗅闻AO、NApO和ApCO。
酒精输注增强了NAc以及眶额、额内侧和楔前叶/后扣带回区域中AO与NApO之间的对比。在眶部、额内侧、楔前叶和后扣带回/压后皮质区域，AO与刺激性对照气味（ApCO；巧克力和葡萄）之间的对比同样更大，最显著的发现是后扣带回/压后皮质区域的反应增强。眶部区域类似于先前显示对食物线索诱导的活动表现出与饱腹感相关下降的区域。
结果表明，起始接触酒精会使边缘系统网络对酒精线索更敏感，可能增强饮酒欲望。
