Bluitt Maya N, Muñoz Ana C, Besheer Joyce
Neuroscience Curriculum, School of Medicine, University of North Carolina at Chapel Hill, USA; Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, USA.
Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, USA.
Alcohol. 2025 Jun;125:43-52. doi: 10.1016/j.alcohol.2025.03.003. Epub 2025 Mar 17.
Continued alcohol use despite negative consequences is a defining feature of alcohol use disorder (AUD). It remains poorly understood whether individual variability in drinking despite negative consequences is due to inherent differences or emerges after prolonged alcohol use. The goal of the present study was to use a rat model of drinking despite negative consequences to assess individual differences in foot shock-punished alcohol self-administration prior to and following alcohol vapor exposure in male Wistar rats. After baseline operant self-administration was established, rats underwent additional self-administration sessions in which random, response-contingent foot shock punishment was introduced. Average percent change from baseline was calculated for each rat during punished sessions and rats were classified into shock-sensitive (SS) and shock-resistant (SR) subgroups using the top and bottom thirds. Rats then underwent 3 cycles of air or alcohol vapor exposure every other week, with unpunished self-administration sessions occurring during the intervening weeks. Following the last vapor cycle, rats were re-assessed for resistance to foot shock during punished self-administration sessions. Alcohol vapor exposure had no effect on punished self-administration overall, nor by subgroup. Examination of individual differences showed that rats classified as SR showed increased unpunished self-administration relative to baseline regardless of air vs. vapor condition. These data suggest that alcohol history has a minimal effect on individual differences in foot shock-punished self-administration.
尽管存在负面后果仍持续饮酒是酒精使用障碍（AUD）的一个决定性特征。尽管存在负面后果，但饮酒的个体差异是由于内在差异还是在长期饮酒后出现，目前仍知之甚少。本研究的目的是使用一种尽管存在负面后果仍会饮酒的大鼠模型，来评估雄性Wistar大鼠在酒精蒸汽暴露之前和之后，足部电击惩罚性酒精自我给药的个体差异。在建立基线操作性自我给药后，大鼠接受额外的自我给药实验，实验中引入随机的、与反应相关的足部电击惩罚。计算每只大鼠在惩罚实验期间相对于基线的平均变化百分比，并使用上下三分之一将大鼠分为电击敏感（SS）和电击抵抗（SR）亚组。然后，大鼠每隔一周接受3个周期的空气或酒精蒸汽暴露，在中间的几周进行无惩罚的自我给药实验。在最后一个蒸汽周期后，在惩罚性自我给药实验中重新评估大鼠对足部电击的抵抗力。酒精蒸汽暴露对整体惩罚性自我给药没有影响，对亚组也没有影响。对个体差异的检查表明，无论空气还是蒸汽条件下，被归类为SR的大鼠相对于基线显示出无惩罚自我给药的增加。这些数据表明，酒精使用史对足部电击惩罚性自我给药的个体差异影响最小。
