Objective To observe the protective effect of modified Baishile Decoction on hippocampal neuronal cells cultured in vitro;To explore its mechanism of treating post-stroke depression.Methods Hippocampal neuronal cells from mammary rats were isolated and cultured in vitro,cell injury was induced by oxygen glucose deprivation combined with lipopolysaccharide.The cells were divided into normal group,model group,blank serum group(10%)and modified Baishile Decoction containing serum group(10%).Invertedmicroscope was used to observe cell morphological changes,CCK-8 method was used to detect cell survival rate,Hoechst33342 staining was used to observe apoptosis,ELISA was used to detect Glu,5-HT,TNF-α,IL-1β,and IL-6 contents in cell supernatant,the expressions of purinergic P2X7 receptor(P2X7R)and NOD-like receptor protein 3(NLRP3)were detected by immunofluorescence staining.Results Compared with the normal group,the hippocampal neurons in the model group showed significant changes in cell morphology,the cell survival rate significantly decreased(P<0.01),the cell apoptosis increased(P<0.01);Glu,TNF-α,IL-1β,IL-6 contents in cell supernatant significantly increased(P<0.05,P<0.01),5-HT content significantly decreased(P<0.01),P2X7R and NLRP3 expressions in hippocampal neuronal cells significantly increased(P<0.01).Compared with the model group,the morphology of hippocampal neurons in modified Baishile Decoction containing serum group was significantly improved,the cell survival rate significantly increased(P<0.01),the cell apoptosis reduced(P<0.01);Glu,TNF-α and IL-1β content in cell supernatant significantly reduced(P<0.05,P<0.01),5-HT content significantly increased(P<0.01),and P2X7R and NLRP3 expressions in hippocampal neuronal cells significantly decreased(P<0.01).Conclusion Modified Baishile Decoction may exert a protective effect on oxidative glucose deprivation combined with lipopolysaccharide induced hippocampal neuronal inflammation damage by inhibiting the P2X7R/NLRP3 signaling pathway,regulating neurotransmitter secretion,and inhibiting inflammatory factor release,thus treating post-stroke depression.