精氨琥珀酸合成酶
一氧化氮
一氧化氮合酶
化学
生物化学
细胞培养
巨噬细胞
精氨琥珀酸裂解酶
精氨酸
酶
生物
精氨酸酶
遗传学
有机化学
氨基酸
体外
作者
Andreas K. Nüssler,Timothy R. Billiar,Z.Z. Liu,Sidney M. Morris
标识
DOI:10.1016/s0021-9258(17)42251-4
摘要
In macrophages and other cell types, bacterial lipopolysaccharide and certain cytokines stimulate nitric oxide (NO) production via expression of the inducible isoform of nitric oxide synthase (NOS). Citrulline, which is the coproduct of NOS-catalyzed metabolism of arginine, can be recycled to arginine by the action of argininosuccinate synthetase and argininosuccinate lyase, which are present at high levels in hepatocytes and renal tubular cells but normally at very low levels in other cell types such as macrophages. The present study demonstrates that lipopolysaccharide and interferon-gamma, which induce NOS in the murine macrophage cell line RAW 264.7, also coinduce activity and mRNA for argininosuccinate synthetase, which is limiting for arginine synthesis. Argininosuccinate lyase activity and mRNA abundance are unaffected. Induction of argininosuccinate synthetase is not blocked by NG-monomethyl-L-arginine, a potent inhibitor of NOS, indicating that argininosuccinate synthetase induction is not the consequence of depleting cellular arginine levels by NOS. Because plasma levels of arginine are limiting for NO synthesis, enhanced cellular capacity to regenerate arginine from citrulline could play a significant role in regulating NO production, especially under conditions where the inducible isoform of NOS is expressed.
科研通智能强力驱动
Strongly Powered by AbleSci AI