Ernest Gallo Clinic and Research Center, Wheeler Center for the Neurobiology of Addiction, and Department of Neurology, University of California, San Francisco, Emeryville, California 94608, USA.
J Neurosci. 2010 Mar 31;30(13):4746-56. doi: 10.1523/JNEUROSCI.0197-10.2010.
Nucleus accumbens (NAc) inactivation increases food intake, indicating that NAc neurons exert ongoing inhibition of feeding. We previously described a subpopulation of NAc neurons that pause during sucrose licking and proposed that the pause permits consumption. We tested this hypothesis by first recording NAc neurons during sucrose consumption, and then electrically stimulating through the same electrodes. A large proportion of NAc shell and core neurons were inhibited during sucrose consumption, and local electrical stimulation abruptly interrupted licking. Effective stimulation sites were more anterior than ineffective sites in NAc. At low stimulus intensities, licking resumed immediately on stimulation offset. The latency to lick resumption from NAc neuron inhibition onset ( approximately 460 ms) was very similar to that after electrical stimulation offset ( approximately 440 ms). These results directly support the hypothesis that a significant subpopulation of NAc neurons inhibit palatable food consumption and that a pause in their firing is required to initiate and maintain consumption.
伏隔核(NAc)失活会增加食物摄入量,表明 NAc 神经元对进食有持续的抑制作用。我们之前描述了 NAc 神经元的一个亚群,它们在舔食蔗糖时会暂停,并提出暂停可以促进进食。我们通过首先在蔗糖消耗期间记录 NAc 神经元的活动,然后通过相同的电极进行电刺激来验证这个假说。在蔗糖消耗期间,NAc 壳核的大部分神经元被抑制,局部电刺激会突然中断舔食。在 NAc 中,有效的刺激部位比无效的刺激部位更靠前。在低刺激强度下,刺激结束后舔食会立即恢复。从 NAc 神经元抑制开始到舔食恢复的潜伏期(约 460 毫秒)与电刺激结束后的潜伏期(约 440 毫秒)非常相似。这些结果直接支持了这样一个假设,即 NAc 神经元的一个重要亚群抑制美味食物的摄入,并且它们的放电暂停是启动和维持摄入所必需的。