Abstract: OBJECTIVE: To explore the protective effect of Schisandrins extract on liver ultrastructure in rats with CCl4 poisoning. METHODS: Twenty five Wistar rats were randomly divided into the control group, the CCl4 poisoned 24 h and 10 d groups, the Schisandrins 24 h and 10 d groups, five groups with 5 rats in each group. The rats of the CCl4 poisoned and the Schisandrins groups were given one peritoneal injection of CCl4(200 ml/L in vegetable oil) at a dosage of 0.2 ml/100 g body weight, the rats of the control group were given the same volume of vegetable oil. Then Schisandrins extract(0.5 ml/100 g body weight)were given orally to rats of the Schisandrins group daily，while saline was given to rats of the poisoned and the control groups. The rats were sacrificed at different time points. The morphologic changes of the hepatocytes were examined by transmission electron microscopy. RESULTS: The ultrastructure of hepatocytes of rats were changed in the CCl4 poisoned 24 h group, the cytoplasm of hepatocytes was loosed and vacuolated, mitochondria were swollen, with cristae breakdown or loss, and the endoplasmic reticulum appeared lamellar. The nuclear membrane was shrunken and ruptured, and the nuclear chromatin condensed and marginated. The hepatocytic nuclei showed obvious atypia in rats of the CCl4 10 d group. By comparing with that of the CCl4 group,the ultrastructure of hepatocytes in rats of the schisandrins group was less severely damaged. CONCLUSION: The use of Schisandrins extract in the treatment of CCl4 poisoned rats exerted a protective effect on liver ultrastructure.

Key words: CCl4, rat, Schisandrins, liver, ultrastructure