AJP - Endocrinology and Metabolism, Vol 251, Issue 4 373-E378, Copyright © 1986 by American Physiological Society
Increased rate of purine biosynthesis in rat liver after bilateral adrenalectomy
M. Itakura, N. Maeda and K. Yamashita
In bilaterally adrenalectomized rat liver the increased rate of de novo
purine synthesis was shown by the increased [14C]glycine incorporation into
hepatic acid-soluble purines with unchanged rapidly miscible glycine pool
size and its turnover rate and by the increased rate of chasing of
radiolabeled purines. At 24 h after adrenalectomy, the rate of de novo
purine synthesis increased by 70%, 5-phosphoribosyl-1-pyrophosphate (PRPP)
content increased by 200%, the specific activity of
amidophosphoribosyltransferase (EC 2.4.2. 14; ATase) did not change, ATP
and GTP showed a 33 and 24% decrease, and AMP and ADP showed a 245 and 38%
increase. Combined, the metabolic pool size data reflected an unchanged
total inhibitory potential on ATase. Replacement with corticosterone
acetate for 24 h partially restored some of these abnormalities. These
results suggest that the increase in the rate of de novo purine synthesis
in adrenalectomized rat liver is secondary to increased catabolism of
purine ribonucleotides and mediated by increased PRPP concentrations.
