[cAMP-dependent regulation of glycogen phosphorolysis in rat liver after exposure to tetrachloromethane].

The cAMP-dependent enzymic system of glycogen phosphorolysis control was studied in the liver and myocardium of rats 2-168 h after tetrachloromethane single administration. It is shown that 2 h after the tetrachloromethane administration the content of cAMP in the rat liver rises and adenylate cyclase activity increases, which is accompanied by activation of phosphorylase b kinase, glycogen phosphorylase and a sharp fall in the content of glycogen; activation of phosphorylase a phosphatase is observed as well. No changes are found in the content of cAMP, glycogen and in the activity of glycogen phosphorylase in the myocardium. The tetrachloromethane effect disturbs the ratio between molecular forms of glycogen phosphorylase in the rat liver. There occurs a considerable shift towards prevalence of phosphorylase a as compared to phosphorylase b with the total amount of the enzyme (a + b) decreased.