Ventura Rossella, Morrone Cristina, Puglisi-Allegra Stefano
Santa Lucia Foundation, European Centre for Brain Research (CERC), Via del Fosso di Fiorano 65, 00143 Rome, Italy.
Proc Natl Acad Sci U S A. 2007 Mar 20;104(12):5181-6. doi: 10.1073/pnas.0610178104. Epub 2007 Mar 9.
Recent evidence suggests that rewarding and aversive stimuli affect the same brain areas, including medial prefrontal cortex and nucleus accumbens. Although nucleus accumbens is known to respond to salient stimuli, regardless of their hedonic valence, with selective increased dopamine release, little is known about the role of prefrontal cortex in reward- and aversion-related motivation or about the neurotransmitters involved. Here we find that selective norepinephrine depletion in medial prefrontal cortex of mice abolished the increase in the release of norepinephrine by prefrontal cortex and of dopamine by nucleus accumbens that is induced by food, cocaine, or lithium chloride and impaired the place conditioning induced by both lithium chloride (aversion) and food or cocaine (preference). This is evidence that prefrontal cortical norepinephrine transmission is necessary for motivational salience attribution to both reward- and aversion-related stimuli through modulation of dopamine in nucleus accumbens, a brain area involved in all motivated behaviors.
近期证据表明,奖励性和厌恶性刺激会影响相同的脑区,包括内侧前额叶皮质和伏隔核。尽管已知伏隔核会对显著刺激作出反应,无论其享乐效价如何,都会选择性地增加多巴胺释放,但对于前额叶皮质在与奖励和厌恶相关的动机中的作用或所涉及的神经递质知之甚少。在此,我们发现,小鼠内侧前额叶皮质中去甲肾上腺素的选择性耗竭消除了前额叶皮质去甲肾上腺素释放的增加以及伏隔核多巴胺释放的增加,后者是由食物、可卡因或氯化锂诱导产生的,并且损害了由氯化锂(厌恶)以及食物或可卡因(偏好)诱导产生的条件性位置反射。这证明前额叶皮质去甲肾上腺素传递对于通过调节伏隔核中的多巴胺,将动机显著性归因于与奖励和厌恶相关的刺激而言是必要的,而伏隔核是一个涉及所有动机行为的脑区。