Objective: To investigate the hepatic injury induced by multiple administration of controlled Sophorae Tonkinensis Radix et Rhizoma(STRR)in rats and its toxic mechanisms. Method: The quality of extract of STRR was controlled by purchasing the herbs from the same source and the extraction:1 hour of extraction

6 times amount of water

and twice extraction. Then the extract was used in animal experiment. The rats were divided randomly into 5 groups:blank control group

the extrad-STRR low dose group(1 g·kg-1)

medium dose group(4 g·kg-1)

high dose group(16 g·kg-1)and positive control group(10%CCl4). The rats were given the corresponding extract by gavage for 14 days. The toxic effect and body weight of rats were observed.After last administration

the rats were anaesthetized by 25% urethane

and blood was collected from aorta abdominalis

then the liver function and tumor necrosis factor-α(TNF-α)

interleukin(IL)-6

IL-10 in serum was detected. The livers were collected and weighed

organ index was calculated. The hepatic histopathology was examined. The value of superoxide dismutase(SOD)

malanyldiadehyde(MDA)

GSH in liver was investigated. Result: After administration of STRR for 7 days

reduced locomotor activity of the rats in high dose group was found. Compared with blank control group

the level of ALT

ALP

TBA increased significantly in high dose group and positive control group (P<0.01 or P<0.05) after 14 day of administration. Hepatocyte swelling and inflammatory cell infiltrate were evident in high dose group. The organ index of liver in high dose group increased significantly. The level of IL-6

TNF-α and the content of MDA

GSH also increased significantly in high dose group. The content of SOD in liver and SOD/MDA ratio decreased significantly in high group. Conclusion: Liver injury in rats was induced after administration of large dose of STRR decoction. Oxidative stress

inflammation may be one of the hepatic toxic mechanisms

and the mechanisms is similar to the CCl4 to some extent.