Spin trapping of nitric oxide produced in vivo in septic‐shock mice

FEBS Letters

Komarov, Andrei M.¹  Lai, Ching-San¹ 

[1] Biophysics Research Institute, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA

关键词: Electron paramagnetic resonance;    Spin trapping;    Nitric oxide;    Lipopolysaccharide;    N G-Monomethyl-l-arginine;    Septic shock;    ·NO;    nitric oxide;    EPR;    electron paramagnetic resonance;    MGD;    N-methyl-d-glucamine-dithiocarbamate;    DETC;    diethyldithiocarbamate;    NMMA;    N G-monomethyl-l-arginine;   

DOI  :  10.1016/0014-5793(94)00422-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A nitric oxide (•NO) spin-trapping technique combined with electron paramagnetic resonance (EPR) spectroscopy has been employed to measure the in vivo production of •NO in lipopolysaccharide (LPS)-treated mice. The in vivo spin-trapping of •NO was performed by injecting into mice a metal—chelator complex, consisting of N-methyl-d-glucamine dithiocarbamate (MGD) and reduced iron (Fe²⁺), that binds to •NO and forms a stable, water-soluble [(MGD)₂-Fe²⁺-NO] complex, and by monitoring continuously the in vivo formation of the latter complex using an S-band EPR spectrometer. At 6 h after intravenous injection of LPS, a three-line EPR spectrum of the [(MGD)₂-Fe²⁺-NO] complex, was observed in the blood circulation of the mouse tail; the [(MGD)₂-Fe²⁺] complex was injected subcutaneously 2 h before EPR measurement. No signal was detected in control groups. Administration of N ^G-monomethyl-l-arginine, an •NO synthase inhibitor, caused a marked reduction in the in vivo EPR signal of the [(MGD)₂-Fe²⁺-NO] complex, suggesting that the •NO detected is synthesized via the arginine-nitric oxide synthase pathway. The results presented here demonstrated, for the first time, the in vivo real time measurement of •NO in the blood circulation of conscious, LPS-treated animals.

【 授权许可】

Unknown