Suppression by Chai-hu-gui-zhi-tang of the development of liver lesions induced by N-nitrosomorpholine in Sprague-Dawley rats

The effects of Chai-hu-gui-zhi-tang (TJ-10) on the development of liver lesions induced by N-nitrosomorpholine and on labeling and apoptotic indices were investigated in male Sprague-Dawley rats. Rats were given chow pellets containing 0.5 or 1.0% TJ-10 and, from the beginning of the experiment, were given drinking water containing N-nitrosomorpholine for 8 weeks. Visible white liver nodules, cellular alteration foci, and hepatic foci staining positively for glutathione-S-transferase, placental type, were examined macroscopically or histochemically. In week 16, TJ-10 at both dosages significantly reduced the incidence, and/or number of visible white nodules and hepatic lesions. Quantitative histologic analysis also showed that prolonged feeding of TJ-10 at both dosages significantly reduced the number of hepatic foci positive for glutathione-S-transferase, placental type. Administration of TJ-10 at both dosages also significantly decreased the labeling index of adjacent liver and significantly increased the apoptotic index of adjacent liver but had no significant effect on those of neoplastic lesions. These findings indicate that TJ-10 suppresses the development of liver lesions and suggest that this effect might be related to TJ-10's inhibition of cell proliferation and induction of apoptosis in adjacent hepatocytes. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.