Effects of schizandrins and diphenyl dimethyl bicarboxylate on enzymes of liver smooth and rough endoplasmic reticula in rats

Schizandrins and DDB are hepatoprotective agents and inducers of the hepatic cytochrome P-450 in animals. The effects of these agents on enzymes of smooth and rough endoplasmic reticula (SER, RER) were investigated in the present study. Oral administrations of schizandrin B, schizandrol B (150 mg/kg) or DDB (200 mg/kg) to mice once daily for 3 d induced a significant increase of cytochrome P-450 in SER but not in RER. Schizandrol B and DDB also increased NADPH-cytochrome C reductase and aminopyrine demethylase activities as well as protein concentration in SER. In addition, schizandrol B markedly enhanced the activity of glucose-6-phosphatase in SER. Whereas schizandrin B was without these actions. The results indicated that schizandrin B, schizandrol B and DDB selectively induced different effects on drug metabolism enzymes in SER.