Objective: The aim of this study was to explore the effects of Guizhi plus Gegen decoction(GGD) on spacial memory and inflammatory cytokines and microglia in hippocampus of neuroinflammatory mice induced by lipopolysaccharides(LPS) and its probable mechanism. Method: Totally 63 male ICR mice were randomly divided into 5 groups

i ethe normal control group(Control

n=13)

the model group(Model

n=13)

the low dose GGD group(GGD-low

n=10)

the high dose GGD group (GGD-high

n=14)

and the Minocycline positive control(Positive control

n=13

0.05 g·kg-1). AD neuroinflammatory model mice were established through intraperitoneally injected with LPS(0.33 mg·kg-1). Mice had been administered by gastrogavage for 4 weeks with low dose GGD(6 g·kg-1)or high dose GGD(12 g·kg-1).Then

Morris water maze were practiced respectively to observe the effects of GGD on spacial memory

and inflammatory cytokines and microglia of hippocampus in neuroinflammatory mice were tested by ELISA and immunofluoresent assay. Result: The escape latency of model mice induced by LPS increased significantly(P<0.05) in Morris water maze.After treated with low dose or high dose GGD

the model mice had evidently shortened their escape latency (P<0.05

P<0.01). Also

LPS increased significantly content of tumor necrosis factor-α(TNF-α) and interleuktin-1β(IL-1β) in hippocampus(P<0.01).Microglia in hippocampus of Model mice are characterized by the rise in the numbers and activated phenomenon such as radial.GGD reduced the content of TNF-α and IL-1β at some degree(P<0.05)

and regulated the activated phenomenon of microglia. Conclusion: These results indicate that GGD could improve spacial memory disorder in neuroinflammatory mice induced by LPS.Its mechanism may be possibly correlated with its regulatory effects of GGD on activated microglia and content of TNF-α and IL-1β in hippocampus.