Catabolism of purine ribonucleotides and glucocorticoid hormones in the rat.

We have studied, in vivo, the catabolism of purine nucleotides (inosinic, guanylic and adenylic acid) in the rat and its regulation by the glucocorticoid hormones, following the behavior of liver xanthine oxidase and the incorporation of formate-14C into urinary allantoin. An original method for purification of urinary allantoin has been developed. A slight acceleration of purine catabolism in adrenalectomized rats--both treated and untreated with corticosterone--was observed, while the normal behavior was restored during cortisone and cortisol treatment. The liver xanthine oxidase activity is unchanged in the different conditions. We conclude that the glucocorticoid hormones have only a slight, not relevant and probably not specific effect on purine catabolism in the whole body.