Avena Nicole M, Rada Pedro, Hoebel Bartley G
Department of Psychology, Princeton University, Princeton, NJ 08540, USA.
Neurosci Biobehav Rev. 2008;32(1):20-39. doi: 10.1016/j.neubiorev.2007.04.019. Epub 2007 May 18.
[Avena, N.M., Rada, P., Hoebel B.G., 2007. Evidence for sugar addiction: Behavioral and neurochemical effects of intermittent, excessive sugar intake. Neuroscience and Biobehavioral Reviews XX(X), XXX-XXX]. The experimental question is whether or not sugar can be a substance of abuse and lead to a natural form of addiction. "Food addiction" seems plausible because brain pathways that evolved to respond to natural rewards are also activated by addictive drugs. Sugar is noteworthy as a substance that releases opioids and dopamine and thus might be expected to have addictive potential. This review summarizes evidence of sugar dependence in an animal model. Four components of addiction are analyzed. "Bingeing," "withdrawal," "craving" and "cross-sensitization" are each given operational definitions and demonstrated behaviorally with sugar bingeing as the reinforcer. These behaviors are then related to neurochemical changes in the brain that also occur with addictive drugs. Neural adaptations include changes in dopamine and opioid receptor binding, enkephalin mRNA expression and dopamine and acetylcholine release in the nucleus accumbens. The evidence supports the hypothesis that under certain circumstances rats can become sugar dependent. This may translate to some human conditions as suggested by the literature on eating disorders and obesity.
[阿韦纳，N.M.，拉达，P.，霍布尔，B.G.，2007年。糖成瘾的证据：间歇性过量摄入糖的行为和神经化学影响。《神经科学与行为评论》XX(X)，XXX - XXX]。实验问题是糖是否会成为一种滥用物质并导致一种自然形式的成瘾。“食物成瘾”似乎是合理的，因为进化来对自然奖励做出反应的大脑通路也会被成瘾药物激活。糖作为一种能释放阿片类物质和多巴胺的物质值得关注，因此可能具有成瘾潜力。这篇综述总结了动物模型中糖依赖的证据。分析了成瘾的四个组成部分。“暴饮暴食”“戒断反应”“渴望”和“交叉致敏”都给出了操作性定义，并以糖暴饮暴食作为强化物进行了行为学证明。然后将这些行为与成瘾药物也会出现的大脑神经化学变化联系起来。神经适应性变化包括伏隔核中多巴胺和阿片受体结合、脑啡肽信使核糖核酸表达以及多巴胺和乙酰胆碱释放的变化。证据支持这样的假设，即在某些情况下大鼠会对糖产生依赖。正如关于饮食失调和肥胖的文献所表明的，这可能会转化为一些人类的情况。
