Fear memory contextualization is critical for selecting adaptive behavior to survive.Contextual fear conditioning(CFC)is a classical model for elucidating related underlying neuronal circuits.The primary visual cortex...Fear memory contextualization is critical for selecting adaptive behavior to survive.Contextual fear conditioning(CFC)is a classical model for elucidating related underlying neuronal circuits.The primary visual cortex(V1)is the primary cortical region for contextual visual inputs,but its role in CFC is poorly understood.Here,our experiments demonstrated that bilateral inactivation of V1 in mice impaired CFC retrieval,and both CFC learning and extinction increased the turnover rate of axonal boutons in V1.The frequency of neuronal Ca^(2+)activity decreased after CFC learning,while CFC extinction reversed the decrease and raised it to the naïve level.Contrary to control mice,the frequency of neuronal Ca^(2+)activity increased after CFC learning in microglia-depleted mice and was maintained after CFC extinction,indicating that microglial depletion alters CFC learning and the frequency response pattern of extinction-induced Ca^(2+)activity.These findings reveal a critical role of microglia in neocortical information processing in V1,and suggest potential approaches for cellular-based manipulation of acquired fear memory.展开更多
基金supported by the National Natural Science Foundation of China(61735016)the Natural Science Foundation of Zhejiang Province(LR20F050002)+3 种基金the Key R&D Program of Zhejiang Province(2020C03009 and 2021C03001)the Zhejiang Leading Innovation and Entrepreneurship Team(202099144)the CAMS Innovation Fund for Medical Sciences(2019-I2M-5-057)Fundamental Research Funds for the Central Universities.
文摘Fear memory contextualization is critical for selecting adaptive behavior to survive.Contextual fear conditioning(CFC)is a classical model for elucidating related underlying neuronal circuits.The primary visual cortex(V1)is the primary cortical region for contextual visual inputs,but its role in CFC is poorly understood.Here,our experiments demonstrated that bilateral inactivation of V1 in mice impaired CFC retrieval,and both CFC learning and extinction increased the turnover rate of axonal boutons in V1.The frequency of neuronal Ca^(2+)activity decreased after CFC learning,while CFC extinction reversed the decrease and raised it to the naïve level.Contrary to control mice,the frequency of neuronal Ca^(2+)activity increased after CFC learning in microglia-depleted mice and was maintained after CFC extinction,indicating that microglial depletion alters CFC learning and the frequency response pattern of extinction-induced Ca^(2+)activity.These findings reveal a critical role of microglia in neocortical information processing in V1,and suggest potential approaches for cellular-based manipulation of acquired fear memory.
