Positive memory increases cataplexy-like behaviors in narcolepsy mice as revealed using conditioned place preference test

BMC Neuroscience

Research Article

Koki Yamamoto¹  Mayuko Yoshida¹  Tomoyuki Kuwaki¹ 

[1] Department of Physiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Sakuragaoka 8-35-1, 890-8544, Kagoshima, Japan;

关键词: Positive emotion;    Cataplexy behavior;    Nucleus accumbens;    Orexin neurons;    Extracellular signal-regulated kinase;   

DOI  :  10.1186/s12868-022-00772-2

 received in 2022-06-21, accepted in 2022-12-20,  发布年份 2022

来源: Springer

【 摘 要 】

BackgroundCataplexy is a loss of muscle tone that can lead to postural collapse, disturbing the daily life of narcolepsy patients; it is often triggered by positive emotions such as laughter in human patients. Narcolepsy model mice also show cataplexy, and its incidence increases in response to positive emotion-inducing stimuli such as chocolate and female courtship. Although such observation indicates a positive emotion-related nature of cataplexy in narcolepsy mice, they also show cataplexy without any apparent triggering stimulus ~ (spontaneous cataplexy). Therefore, we hypothesized that some spontaneous cataplexy in narcoleptic mice might indicate the remembering of happy moments.ResultsTo test our hypothesis, we did a conditioned place preference test on orexin/hypocretin neuron-ablated (ORX-AB) mice, one of the animal models of human narcolepsy, and counted the number of cataplexy-like behaviors. ORX-AB mice successfully remembered the chocolate-associated chamber, and the number of cataplexy-like behaviors significantly increased in the chocolate-associated chamber but not in the control chamber. In addition, ORX-AB mice remembered the aversive odor-associated chamber and avoided entering without affecting the number of cataplexy-like behaviors. Finally, similar activation of the nucleus accumbens, a positive emotion-related nucleus, was observed during both spontaneous and chocolate-induced cataplexy behaviors.ConclusionsThese results support our hypothesis and will promote the usefulness of a narcolepsy mice model in emotion research and serve as a basis for a better understanding of cataplexy in narcolepsy patients.

【 授权许可】

CC BY   
© The Author(s) 2022

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