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A molecularly defined brain circuit module for regulating panic-like defensive state
Miao Zhao1, Li Zhang1, Zhenhua Chen2
1National Institute of Biological Sciences, Beijing, China.
Abstract:
Panic is an episode of strong defensive state, characterized by intense fear and severe physical symptoms such as elevated cardiorespiratory activities. How the brain generates panic state remains poorly understood. Here, we developed a robot-based experimental paradigm to evoke panic-like defensive state in mice. When stimulated by the robot, mice exhibited jumping escapes and elevated cardiorespiratory activities. With this paradigm, we identified Cbln2-expressing (Cbln2+) neurons in the posterior hypothalamic nucleus (PHN) as a key neuronal population essential for the induction of panic-like defensive state. Activation of Cbln2+ PHN neurons induced behavioral and physical symptoms of panic-like defensive state. These neurons were strongly activated by noxious mechanical stimuli and encode jumping escape vigor. They were synaptically innervated by anxiety-associated brain areas and provoked panic-like defensive state via their projection to the periaqueductal gray. Together, our results reveal a molecularly defined circuit module that regulates the panic-like defensive state in mice.
Insights
Researchers identified specific brain neurons that trigger panic-like defensive states in mice. Activating these Cbln2-expressing neurons in the posterior hypothalamic nucleus (PHN) induced fear and physical symptoms, revealing a key circuit for panic.
Area of Science:
- Neuroscience
- Behavioral Biology
- Animal Models
Background:
- Panic attacks involve intense fear and physical symptoms, but the underlying brain mechanisms are not fully understood.
- Existing research lacks clear identification of specific neural circuits responsible for generating panic states.
Purpose of the Study:
- To develop a novel experimental paradigm for reliably inducing panic-like defensive states in mice.
- To identify specific neuronal populations and circuits involved in the generation of panic-like states.
Main Methods:
- Development of a robot-based system to evoke panic-like defensive behaviors in mice.
- Utilized the paradigm to investigate neuronal activity, focusing on Cbln2-expressing neurons in the posterior hypothalamic nucleus (PHN).
- Examined neuronal projections and activation patterns in response to stimuli and during panic-like states.
Main Results:
- The robot paradigm successfully induced jumping escapes and elevated cardiorespiratory activity, indicative of a panic-like state.
- Cbln2-expressing neurons in the PHN were identified as crucial for inducing panic-like defensive states.
- Activation of these neurons mimicked panic symptoms and was linked to noxious stimuli and escape vigor, projecting to the periaqueductal gray.
Conclusions:
- The study successfully established a mouse model for panic-like states using a robot-based paradigm.
- Cbln2+ neurons in the PHN represent a key molecularly defined neural module regulating panic-like defensive states.
- This finding provides a foundation for understanding the neurobiology of panic and developing targeted interventions.
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