Effect of Acute Administration of a Large Dose of Ethanol on Hepatic Contents of Adenine Nucleotides and Their Degradation Products in Rats
1990 年 8 巻 2 号 p. 141-151
詳細
1990 年 8 巻 2 号 p. 141-151
A single oral administration of ethanol (5g/kg) to fasted rats significantly increased the hepatic content of ATP and of total adenine nucleotides after a lag period of 1h. The ADP content gradually decreased, and the AMP content increased. There was no change in the energy charge. The phosphorylation state significantly increased at 3h and thereafter, and the adenylate kinase mass-action ratio was elevated during the intoxication. The IMP content significantly decreased at 3h and thereafter. A small but significant increase in the hypoxanthine content was noted only in the early phase during the intoxication. This early increase after the ethanol administration was not enhanced by the pretreatment with allopurinol, by which the hepatic activities of xanthine oxidase and xanthine dehydrogenase were inhibited by more than 90%. Xanthine was detected only in the liver extracts from rats pretreated with allopurinol, but there was no significant effect of the ethanol loading on the xanthine content.
These results demonstrate that, during acute intoxication with a large dose of ethanol, the overall metabolism of adenine nucleotides shifts toward their accumulation rather than degradation, that the increase in hypoxanthine is rather small and transient, and that xanthine is produced from metabolites other than hypoxanthine.
