The content of adenosine polyphosphates in fatty livers.

It has been reported in a previous paper (Dianzani, 1954) that uncoupling of oxidative phosphorylation occurs in fatty livers. Adenosine triphosphatase (ATPase) activity of mitochondria isolated from fatty livers is increased. Conversely, many substances which inhibit oxidative phosphorylation produce fatty infiltration of the liver when administered intraperitoneally to rats or mice (Dianzani & Scuro, 1956). A decrease of adenosine triphosphate (ATP) and of phosphocreatine has been shown to occur in many organs of rats treated with 3:5-dinitro-o-cresol, a substance which inhibits oxidative phosphorylation (Parker, 1954). From these facts one may expect that ATP concentration in fatty liver is decreased. Only scanty indirect data are available in the literature on organophosphorus compounds in fatty liver. Flock, Bollman & Mann (1936a, b) found a decrease of inorganic orthophosphate in the liver of dogs fed on a hyperlipidic diet, but reported a normal distribution of organophosphorus compounds in the liver of dogs treated with carbon tetrachloride. Kaplan & Greenberg (1944) observed a decrease of high-energy phosphates in fatty livers of rats fed on a hyperlipidic diet. Wagtendonk (1944) and Wagtendonk & Lamfrom (1945) described a marked decrease of ATP and phosphocreatine in liver, kidneys and muscles of rats fed on a diet deficient in vitamin E. It is well known that this deficiency produces fatty infiltration and necrosis in the liver, as well as muscular dystrophy (Himsworth, 1952). Ennor & Stocken (1948), on the contrary, found in the liver of guinea pigs treated with carbon tetrachloride a marked increase of those acid-soluble organophosphorus compounds having insoluble barium salts. This fraction contains mainly ATP, adenosine diphosphate (ADP) and hexose diphosphate. The results of Ennor & Stocken were confirmed by Rowles (1952), who used the enzymic method of Rowles & Stocken (1950) for the determination of ATP. The discrepancy in these results may be perhaps attributed to the different methods that have been used. Since new specific methods are now available for estimation ofATP, the problem ofthe content of ATP in fatty livers has been again investigated, and the results are described here. MATERIAL AND METHODS