The time course of biochemical and histological changes following carbon tetrachloride-induced liver damage in rats of both sexes

A detailed analysis is presented of the time changes in the development of liver damage 6, 12, 24, 48 and 72 hours after i.p. administration of carbon tetrachloride [CCl4] in a dose of 0.75 ml, i.e. 1 200 mg/kg body weight to rats of both sexes. The severity of liver damage was assessed from the histological and biochemical changes of AST, ALT, alkaline phosphatase and GMT serum activity. From our experiments it follows that in male rats the level of transaminases increases earlier than in female rats, as early as 6 h after the administration of CCl4, reaching a maximum 12 h later. These changes prevail for a longer time period, the level of transaminases remaining increased even 72 h after CCl4 administration. In female rats the biochemical changes occur later reaching the maximum elevation of AST and ALT 24 h after CCl4 administration. The values slowly return to normal after 48 h, and after 72 h the levels of transaminases are identical with the control group. The above given biochemical results are in good agreement with the histological findings demonstrating a higher regenerative activity in female rats. This finding was also proved by specific liver DNA activity assay.