Abstract
Brain nitric oxide synthase (NOS), which utilizes NADPH and calcium/calmodulin as cofactors for metabolizing L-arginine to nitric oxide (NO) and L-citrulline, contains recognition sites for the flavins FAD and FMN. Using a spin-trapping technique combined with electron spin resonance spectroscopy, we report that brain NOS generates Superoxide O2.- in a calcium/calmodulin-dependent manner. The "specific inhibitors" of NOS, NG-monomethyl L-arginine (L-NMMA), and NG-nitro-L-arginine methyl ester (L-NAME), have different effects on O2.- generation. For L-NMMA, O2.- production is unaffected, while for L-NAME, inhibition of this free radical is concentration-dependent.
Original language | English (US) |
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Pages (from-to) | 24173-24176 |
Number of pages | 4 |
Journal | Journal of Biological Chemistry |
Volume | 267 |
Issue number | 34 |
State | Published - Dec 5 1992 |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology