Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon 1400-038, Portugal; Champalimaud Clinical Centre, Champalimaud Centre for the Unknown, Lisbon 1400-038, Portugal; NOVA Medical School | Faculdade de Ciencias Medicas, Universidade Nova de Lisboa, Lisbon 1169-056, Portugal.
Champalimaud Research, Champalimaud Centre for the Unknown, Lisbon 1400-038, Portugal.
Neuron. 2020 Jun 3;106(5):778-788.e6. doi: 10.1016/j.neuron.2020.03.009. Epub 2020 Apr 6.
Postingestive nutrient sensing can induce food preferences. However, much less is known about the ability of postingestive signals to modulate food-seeking behaviors. Here we report a causal connection between postingestive sucrose sensing and vagus-mediated dopamine neuron activity in the ventral tegmental area (VTA), supporting food seeking. The activity of VTA dopamine neurons increases significantly after administration of intragastric sucrose, and deletion of the NMDA receptor in these neurons, which affects bursting and plasticity, abolishes lever pressing for postingestive sucrose delivery. Furthermore, lesions of the hepatic branch of the vagus nerve significantly impair postingestive-dependent VTA dopamine neuron activity and food seeking, whereas optogenetic stimulation of left vagus nerve neurons significantly increases VTA dopamine neuron activity. These data establish a necessary role of vagus-mediated dopamine neuron activity in postingestive-dependent food seeking, which is independent of taste signaling.
摄食后营养感应能诱导食物偏好。然而，对于摄食后信号调节觅食行为的能力知之甚少。在这里，我们报告了摄食后蔗糖感应与腹侧被盖区（VTA）迷走神经介导的多巴胺神经元活动之间的因果关系，支持觅食行为。胃内给予蔗糖后，VTA 多巴胺神经元的活动显著增加，而这些神经元中 NMDA 受体的缺失会影响爆发和可塑性，从而消除对摄食后蔗糖传递的杠杆按压。此外，迷走神经肝支的损伤显著损害了摄食后依赖的 VTA 多巴胺神经元活动和觅食行为，而左迷走神经神经元的光遗传刺激则显著增加了 VTA 多巴胺神经元的活动。这些数据确立了迷走神经介导的多巴胺神经元活动在摄食后依赖的觅食行为中的必要作用，该作用不依赖于味觉信号。
