Objective:To explore the effects and mechanism of Salvianolic acid B(SalB)on Parkinson's disease(PD).Methods:Forty-eight C57BL/6 male mice were randomly separated into control group(control)withoutdrugs,model group(MPTP)with intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrah-ydropyridine(MPTP),SalB control group with intraperitoneal injection of SalB,and SalB treatment group(MPTP+SalB).Construction of PD mouse model by intraperitoneal injection of MPTP,and treatment with intraperitoneal injection of SalB.Pole climbing test was applied to assess behavior differences.The time of first black stool excretion and water content of feces were measured to evaluate intestinal dysfunctions.The number of tyrosine hydroxylase(TH)positive cells in substantia nigra and the level of Toll like receptor 4(TLR4)in colon were analyzed by immunohistochemistry.The pathological changes of colonic mucosa were observed by HE staining.The levels of calprotectin(CP)and tumor necrosis factor-α(TNF-α)in colon were determined by ELISA.Western blot was used to determine the level of TH in midbrain,the protein level of TH,tight junction protein(ZO-1),and protein level of TLR4/MyD88/NF-κB signaling pathways which express in colon.Results:Com-pared with the Control group,the climbing time,T-turn time and the first black stool excretion time in MPTP group increased while the fecal water content and the number of TH positive cells in substantia nigra were decreased.Accompanied by TLR4 positive cells in colon,pathological injury score of colonic mucosa,levels of CP and TNF-α in colon increased,expression of TH in midbrain and expression of ZO-1 in colon decreased.Expressions of TLR4,MyD88,Nuclear NF-κB p65 and p-NF-κB p65 in colon increased.Com-pared with MPTP group,SalB treatment shortened the climbing time,T-turn time and the first black stool excretion time in SalB treat-ment group,increased the fecal water content and the number of TH positive cells in substantia nigra,lowered TLR4 positive cells in colon,enhanced expression of TH in midbrain and colon,reduced the pathological injury score of colonic mucosa,significantly decreased levels of CP and TNF-α in colon,enhanced expression of ZO-1 in colon,inhibited expressions of TLR4,MyD88,Nuclear NF-κB p65 and p-NF-κB p65 in colon.Conclusion:SalB can protect the nerves and intestines and alleviate the intestinal inflamma-tion of PD mice,which may be related to the inhibition of TLR4/MyD88/NF-κB signal pathway.