Abstract
This paper was intented to charily the cause of an increase of serum guanase activity in rats following injection of $CCI_4$. The cause of increasing serum guanase was focused on the change of guanase activities in both serum and liver, and additionally, these results were compared with the previously known alanine aminotransferase (ALT). Concomitantly the microscopic investigation on the histologic changes, and the determination of lipid peroxides of liver were combined in this experiment for a correlation to observe that the activity of guanase would be effected by the various degree of hepatic injury induced by $CCI_4$. The serum levels of guanase were increased about 2 fold in the fatty change stage (3-12 days), 5.2 fold representing the peak value in necrosis stage (21days), 4.5 fold in early cirrhosis stage (48 days), and 2 fold in severe cirrhosis stage (92 days). These changes of serum guanase activity showed similar patterns to those of ALT activity and lipid peroxides in liver cell. The changes of liver guanase activities showed an increase, whereas ALT activities in liver were markedly decreased. It is likely that the increase of serum guanase activity is based on the excess leaking of guanase into blood by the result of accelerated enzyme synthesis in liver cell of $CCI_4$ intoxicated rats. In addition, the possibility could not be ruled out, however, that the increase of serum guanase activity would be caused by the alteration of membrane permeability.