Enhancement by phenobarbital of some effects of carbon tetrachloride on mouse liver

Abstract

Corn oil or a corn oil-CCI 4 mixture was administered orally twice a week for 7 or 8 weeks to male Swiss mice maintained without or with phenobarbital Na in the drinking water. There was a significant increase in liver weight in CCl 4-treated mice maintained without phenobarbital Na in the drinking water and killed 48 hr after the last treatment. Histologically, livers from these CCl 4-treated mice were composed of areas of necrosis within lobules of regenerating hepatocytes, but deposition of collagen was scant. Synthesis of DNA, protein and fatty acids in vitro was increased in liver tissue from CCl 4-treated mice. Combined treatment with phenobarbital and CCl 4 produced additional significant increases in liver weight but collagen deposition was meager. In liver tissue from mice treated with both phenobarbital and CCl 4, synthesis of DNA in vitro was significantly increased, protein synthesis was modestly increased and fatty acid synthesis was unchanged when compared with liver tissue from CCl 4-treated mice not additionally given the barbiturate. Thus, phenobarbital did not accelerate or promote cirrhosis in livers of CCl 4-treated mice but did enhance the effects of chronic CCl 4 treatment on liver weight, liver DNA synthesis and to a lesser extent on liver protein synthesis.