EFFECT OF LIPOLYTIC AGENTS ON ADENOSINE AND AMP FORMATION BY FAT-CELLS

被引:22
作者
FAIN, JN
机构
[1] Section of Physiological Chemistry, Division of Biology and Medicine, Brown University, Providence
关键词
Adenine nucleotide; Adenosine metabolism; Allopurinol; AMP formation; Xanthine dehydrogenase;
D O I
10.1016/0005-2760(79)90225-X
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The release and metabolism of adenosine was examined using rat fat cells in which the nucleotide pool had been labeled by incubation with radioactive adenine. The accumulation of adenosine in the medium was near maximal at the start of the incubation and increased only slightly thereafter. Adenosine was rapidly deaminated to inosine and subsequently oxidized to uric acid. In the presence of allopurinol, an inhibitor of xanthine dehydrogenase, hypoxanthine accumulated in the medium as the end-product of adenosine catabolism. Adenosine accumulated in the medium only if fat cells were incubated in the presence of erythro-9-(2-hydroxy-3-nonyl)adenine, an inhibitor of adenosine deaminase. Even in the presence of this inhibitor there was no acceleration of adenosine release by norepinephrine in the presence of theophylline. However, there was an increase in labeled intracellular AMP accumulation by norepinephrine plus theophylline. The increase in labeled AMP correlated with the final free fatty acid to albumin ratio suggesting that the rise in AMP was related to an accumulation of intracellular free fatty acids. The addition of sodium oleate to the medium mimicked the effect of norepinephrine plus theophylline on the accumulation of labeled AMP. These results indicate that AMP rather than adenosine accumulates in isolated fat cells during incubation with lipolytic agents. © 1979.
引用
收藏
页码:510 / 520
页数:11
相关论文
共 18 条