Objective To investigate the protective effect of acupuncture intervention on liver in carbon tetrachloride induced hepatic fibrosis rats and to reveal its impact on extracellular matrix production in the liver tissue.Methods A total of 46 SD rats were randomly divided into control group(n=10)

model group(n=12)

sham group(n=12) and acupuncture group(n=12).Hepatic fibrosis model was established by intraperitoneal injection of 50% olive oil containing CCl4(1 mL/kg)

3 times in the 1st week and twice per week from the 2nd to the 6th week.During the fibrosis model establishment

acupuncture of "Taichong"(LR 3)

"Qimen"(LR 14)

"Ganshu"(BL 18) and "Zusanli"(ST 36) was carried out simultaneously.In the sham group

non-acupuncture points(0.5 cm left to the above-mentioned real points) were punctured.The treatment was conducted 3 times a week in the first three weeks and then twice a week for the last three weeks.Serum levels of hyaluronic acid(HA)

liminin(LN)and precollagen(PCⅢ)were determined by enzyme linked immunosorbent assay for assessing the hepatic fibrosis degree.Primary hepatic stellate cells(HSC) were separated.Western blot assay was used to detect the expression of α-smooth muscle actin(SMA)

α 1(I) collagen

fibronectin

matrix metalloproteinase(MMP)-9(components of extracellular matrix

ECM) and tissue inhibitor of metalloprotei-nase-1(TIMP-1

an inhibitor of MMP-9) proteins of HSC.Real-time quantitative polymerase chain reaction was used to detect the expression levels of α-SMA

α 1(I) collagen and fibronectin genes of HSC.Results Compared with the control group

contents of serum HA

LN and PCⅢ

expression levels of α-SMA

α 1(I) collagen and fibronectin proteins and genes

and TIMP-1 protein of HSC were significantly increased in the model group(P<0.01

P<0.05)

while MMP-9 protein(an enzyme for degradating ECM) expression level of HSC in the model group was down-regulated significantly(P<0.01)

suggesting a formation of hepatic fibrosis

impairment of the liver tissue fibrosis and imbalance of degradation of ECM.H.E.staining showed an ameliorated liver injury(disorder of hepatocyte arrangement

hepatocyte necrosis

formation of pseudolobule

etc.) in the acupuncture group in comparison with the model group.In comparison with the model group

serum HA and LN contents

expression levels of α-SMA

α 1(I) collagen and fibronectin proteins

and α-SMA mRNA and fibronectin mRNA of HSC were down-regulated considerably in the acupuncture group(P<0.05

P<0.01).On the contrary

MMP-9 protein expression level of HSC was up-regulated remarkably in the acupuncture group compared with the model group(P<0.05).No significant changes were found in all the aforementioned indexes in the sham group

and serum PCⅢ content as well as α 1(I) collagen mRNA and TIMP-1 protein expression levels of HSC in the acupuncture group compared with those in the model group(P>0.05).Conclusion Acu-puncture treatment can significantly relieve CCl4-induced hepatic fibrosis in hepatic fibrosis rats probably by inhibiting the synthe-sis and deposite of HA and LN

down-regulating expression levels of α-SMA

α 1(I) collagen and fibronectin proteins

and α-SMA mRNA and fibronectin mRNA of HSC as well as up-regulating MMP-9 protein expression of HSC.