Sweet and bitter taste stimuli activate VTA projection neurons in the parabrachial nucleus
Sweet and bitter taste stimuli activate VTA projection neurons in the parabrachial nucleus
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DOI：
10.1016/j.brainres.2019.02.027
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发表时间：
2019-07-01
期刊：
影响因子：
2.9
通讯作者：
Tokita, Kenichi
中科院分区：
文献类型：
--
作者：
Boughter, John D., Jr.;Lu, Lianyi;Tokita, Kenichi
本研究探讨了脑干的味觉和内脏加工区臂旁核（PBN）向中脑腹侧被盖区（VTA）的神经投射。腹侧被盖区含有大量多巴胺能神经元，这些神经元已被证明在奖赏处理中发挥作用。顺行神经追踪方法首先被用来证实，一个强大的投影从尾侧PBN终止于背侧腹侧被盖区，这个投影是对侧较大。在接下来的实验中，我们结合了双重逆行追踪从腹侧被盖区和味觉腹后内侧丘脑（VPMpc）与味觉诱发的Fos蛋白表达，标记激活的神经元。通过口内插管用蔗糖、奎宁或水刺激小鼠，处理PBN切片用于Fos和逆行示踪剂的免疫荧光检测。示踪剂标记的PBN神经元的分布表明，投射到VTA或VPMpc的细胞群体在很大程度上是独立的。Fos和任一示踪剂双标记的细胞的定量表明，蔗糖和奎宁在激活这两种途径中是有效的。这些结果表明，食欲和厌恶的味道的信息传递到一个关键的中脑奖励接口通过直接从PBN的投射。
This study investigated neural projections from the parabrachial nucleus (PBN), a gustatory and visceral processing area in the brainstem, to the ventral tegmental area (VTA) in the midbrain. The VTA contains a large population of dopaminergic neurons that have been shown to play a role in reward processing. Anterograde neural tracing methods were first used to confirm that a robust projection from the caudal PBN terminates in the dorsal VTA; this projection was larger on the contralateral side. In the next experiment, we combined dual retrograde tracing from the VTA and the gustatory ventral posteromedial thalamus (VPMpc) with taste-evoked Fos protein expression, which labels activated neurons. Mice were stimulated through an intraoral cannula with sucrose, quinine, or water, and PBN sections were processed for immunofluorescent detection of Fos and retrograde tracers. The distribution of tracer-labeled PBN neurons demonstrated that the populations of cells projecting to the VTA or VPMpc are largely independent. Quantification of cells double labeled for Fos and either tracer demonstrated that sucrose and quinine were effective in activating both pathways. These results indicate that information about both appetitive and aversive tastes is delivered to a key midbrain reward interface via direct projections from the PBN.