PBN-PVT projections modulate negative affective states in mice

Area of Science:

• Neuroscience
• Affective Science
• Behavioral Neuroscience

Background:

• Negative affective states significantly impact well-being and survival.
• The parabrachial nucleus (PBN) and thalamic paraventricular nucleus (PVT) are key brain regions involved in regulating emotions.
• The precise function of PBN-PVT projections in emotional processing is not well understood.

Purpose of the Study:

• To investigate the role of projections from the parabrachial nucleus (PBN) to the paraventricular nucleus (PVT) in modulating negative affective states.
• To determine if PBN-PVT pathway activation influences behaviors associated with negative emotions.

Main Methods:

• Utilized optogenetic and chemogenetic techniques to manipulate PBN-PVT pathway activity in mice.
• Recorded neuronal activity in the PVT in response to aversive stimuli.
• Assessed behavioral responses related to negative affect, aversion, and fear.

Main Results:

• PBN neurons project densely to the PVT and form excitatory synapses.
• Activation of the PBN-PVT pathway induced negative affective behaviors without altering pain perception.
• Inhibition of the PBN-PVT pathway reduced aversion and fear-like behaviors.
• Aversive stimuli activated PVT neurons targeted by PBN projections, and PBN-PVT pathway activation potentiated this response.
• Activating PVT neurons receiving PBN input triggered anxiety-like behaviors.

Conclusions:

• PBN-PVT projections play a critical role in the modulation of negative affective states.
• This neural pathway is specifically involved in processing aversion and fear, contributing to anxiety-like behaviors.