OBJECTIVE: To observe the therapeutic effects of Xiaochaihu decoction for liver injury induced by chronic fluorosis in rats

and to explore the protective effects of Xiaochaihu decoction on oxidative stress

so as to provide theoretical basis for the prevention and treatment of fluorosis. METHODS: SD rats were randomly divided into the blank control group

model group

Xiaochaihu decoction experimental group and Xiaochaihu decoction negative control group. The rat model of chronic fluorosis was established with NaF solution（100 mg/L） as fluoride source. The Xiaochaihu decoction experimental group and the negative control group were given Xiaochaihu decoction（7.29 g/kg） by intragastric administration

while other groups were treated with 0.9% sodium chloride solution by intragastric administration. After 90 d of continuous intragastric administration（once a day）

the rats were anesthetized after fasting for 12 h

and the abdominal aorta blood was taken. The liver tissue was dissected under the ice bath

and the liver indicator was calculated. The pathological changes of liver tissue were detected by hematoxylin-eosin staining. Serum ALT and AST levels were detected by microplate method

liver MDA level was detected by thiobarbituric acid method

and liver T-SOD level was detected by microplate method. RESULTS: Compared with the blank control group

the levels of T-SOD

ALT

AST and MDA in the model group increased significantly

and the liver indicators increased significantly

with statistically significant differences（P<0.01）. Pathological sections showed a large number of inflammatory infiltrations and dot necroses in the model group. Compared with the model group

the levels of ALT and AST in the Xiaochaihu decoction experimental group decreased（P<0.05）

the levels of MDA and T-SOD decreased significantly（P<0.01）

and the liver indicators decreased significantly（P<0.01）

with statistically significant differences. Pathological section results showed the pathological damage of liver in rats from Xiaochaihu decoction experimental group was improved to varying degrees

indicating that Xiaochaihu decoction could improve the pathological changes induced by liver injury in rats with chronic fluorosis. CONCLUSIONS: Xiaochaihu decoction has a certain alleviation effect on liver injury induced by chronic fluorosis

and its mechanism may be related to oxidative stress.