Rac1 Signaling in Amygdala Astrocytes Regulates Fear Memory Acquisition and Retrieval

• 作者: Xiao-Cen Fan Chao-Nan Ma Jia-Chen Song Zhao-Hui Liao Nan Huang Xing Liu Lan Ma
• 来源期刊: 神经科学通报（英文版）
• 年，卷（期）: 2021,（7）
• 所属期刊栏目: Original Articles
• 页码范围: 947-958
• 页数: 12页
• 语种: 英文

摘要

The importance of astrocytes in behavior control is increasingly appreciated,but little is known about the effects of their dynamic activity in regulating learning and memory.In the present study,we constructed AAVs of photoactivatable and photoinactivatable Ras-related C3 botulinum toxin substrate 1(Rac1)under the mGFAP promoter,which enabled the manipulation of Rac1 activity in astrocytes by optical stimulation in free-moving mice.We found that both up-regulation and down-regulation of astrocytic Rac1 activity in the basolateral amygdala(BLA)attenuated memory acquisition in a fear conditioning mouse model.Meanwhile,neuronal activation in the BLA induced by memory acquisition was inhibited under both the up-and down-regulation of astrocytic Racl activity during training.In terms of the impact on fear memory retrieval,we found both up-and down-regulation of BLA astrocytic Racl activity impaired memory retrieval of fear conditioning and memory retrieval-induced neu-ronal activation.Notably,the effect of astrocytic Rac1 on memory retrieval was reversible.Our results demonstrate that the normal activity of astrocytic Racl is necessary for the activation of neurons and memory formation.Both activation and inactivation of astrocytic Racl activity in the BLA reduced the excitability of neurons,and thereby impaired fear memory acquisition and retrieval.