PBN-PVT projections modulate negative affective states in mice
Abstract
Long-lasting negative affections dampen enthusiasm for life, and dealing with negative affective states is essential for individual survival. The parabrachial nucleus (PBN) and thalamic paraventricular nucleus (PVT) are critical for modulating affective states in mice. However, the functional roles of PBN-PVT projections in modulating affective states remain elusive. Here, we show that PBN neurons send dense projection fibers to the PVT and form direct excitatory synapses with PVT neurons. Activation of the PBN-PVT pathway induces robust behaviors associated with negative affective states without affecting nociceptive behaviors. Inhibition of the PBN-PVT pathway reduces aversion-like and fear-like behaviors. Furthermore, the PVT neurons innervated by the PBN are activated by aversive stimulation, and activation of PBN-PVT projections enhances the neuronal activity of PVT neurons in response to the aversive stimulus. Consistently, activation of PVT neurons that received PBN-PVT projections induces anxiety-like behaviors. Thus, our study indicates that PBN-PVT projections modulate negative affective states in mice.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file. The behavioral data and imaging analysis results have been made available on Dryad Digital Repository (https://doi:10.5061/dryad.1rn8pk0w4). All MATLAB code has been deposited at: https://github.com/laizishangalali/Xiang/blob/main/zscore_KS_test.m and is publicly available.
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PBN-PVT projections modulate negative affective states in miceDryad Digital Repository, doi:10.5061/dryad.1rn8pk0w4.
Article and author information
Author details
Funding
National Natural Science Foundation of China (31900717)
- Di Mu
China Association for Science and Technology (2019QNRC001)
- Di Mu
Shanghai Association for Science and Technology (19YF1438700)
- Di Mu
National Natural Science Foundation of China (31571086)
- Ling Zhang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experiment procedures were approved by the Animal Care and Use Committee of Shanghai General Hospital (2019AW008).
Copyright
© 2022, Zhu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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