The Basolateral Amygdala To Lateral Septal Nucleus Circuit Regulates Anxiety And Fear Memory In Mouse

Lateral septum(LS)and basolateral amygdala(BLA)are two important brain regions in the limbic system.They are connected with hypothalamus,hippocampus,amygdala,olfactory bulb and many other brain regions.Both of them are involved in a variety of cognitive behaviors including feeding,anxiety,depression,fear memory and social interaction.Although there are many studies in these two brain regions,it is still controversial how they work in normal and pathological conditions.We aimed to study the neural circuits between LS and BLA,and the impact on animal behaviors.Using retro-AAV labeling,we observed the neural circuit from BLA to LS.We injected retro-AAV-Syn-cre-td Tomato into LS and AAV-DIO-Te NT-2A-EGFP into BLA to silence the projection.Using open-field,elevated zero maze test,elevated plus maze test,three chamber test,social juvenile test,tail suspension test,forced swimming test and fear conditioning,we compared the behavioral consequences Silencing LS-projecting BLA neurons with tetanus toxin(Te NT)significantly reduced the anxiety level,and resulted generalization of fear memory.Our preliminary results suggest that BLA-LS circuit may play an important role in anxiety and fear memory,which may shed light on treating neuropathological disorders.Further experiments need to be performed to confirm the conclusion.