Occurrence of adenosine 2',5'-bisphosphate in rat liver

Adenosine 2',5'-bisphosphate (pAp) is present in liver from 2-day-fasted rats, at a concentration of around 1 microM. pAp was obtained through perchloric acid extraction of the liver followed by two successive DEAE-cellulose chromatographies and an ion-pair high-pressure liquid chromatography. Both pAp extracted from liver and that obtained from a commercial source showed the same pattern of hydrolysis by alkaline phosphatase, i.e., more 5'-AMP than 2'-AMP was obtained as an intermediate of the reaction.