578. Preconditioning of Lipopolysaccharide Improves Anxiety-Like Behavior and Brain Inflammation Associated With Chronic Corticosterone Exposure in Mice

Microglia have recently attracted attention as a target for depression treatment. Previously, prior low-dose administration of lipopolysaccharide (LPS preconditioning) inhibited microglial activation by subsequent high-dose LPS administration, suggesting a potential preventive effect on the onset of depression. However, its impact on models other than the high-dose LPS-induced systemic inflammation depressive model was unknown. Therefore, we investigated whether LPS preconditioning is effective in a chronic corticosterone exposure model, to clarify the mechanism of action of LPS preconditioning and its potential application in preventive treatment.