[Detection of the generation of nitric oxide from L-arginine in the murine brain in vivo using EPR].

Abstract

Nitric oxide (NO) was shown by EPR method to be generated via L-arginine-dependent way in brain of mice in vivo. The complexes of diethyldithiocarbamate (DETC) or pirrolidinedithiocarbamate (PDTC) with endogenous or exogenous Fe2+ were used as a traps of NO, which are capable to bind NO resulted in the formation of mononitrosyl iron complexes with DETC or PDTC (MNIC-DETC or PDTC) recovered by EPR method. These complexes were detected in mouse brain in concentration of 2.5 nmole/g of wet tissue for 30 min only when exogenous Fe2+ was injected in to mice. The level of MNIC-DETC (PDTC) was 5 fold increased in brain of mice pretreated for 4 hrs with lipopolysaccharide from Escherichia coli, which induced the inflammation processes. The inhibitor of NO-synthase, NG-nitro-L-arginine attenuated the formation of MNIC-DETC (PDTC) in mouse brain in vivo. Exogenous Fe2+ is suggested to induced the synthesis of NO-synthase in mouse brain.