Effects of a thermal injury on brain and blood nitric oxide (NO) content in the rat.

In the present study, the effects of a thermal injury on the nitric oxide (NO)-ergic system was investigated in freely moving rats. Using a voltammetric method allowing direct and in situ NO measurements, a significant decrease in cortical NO concentration was observed during the 24h following burning procedure. Since in the burning procedure halothane was employed, it was verified that this anaesthetic did not induce significant effect on cortical NO level. Experiments conducted in ex vivo conditions showed that blood NO and nitrites (NO(2)(-)) + nitrates (NO(3)(-)) concentrations increased strongly after burn injury while hypothalamic inducible NO-synthase (NOS(2)) mRNA level decreased significantly. A thermal injury was thus accompanied by a rapid impairment of the NO-ergic pathways, which might partly have been responsible for numerous changes occurring after burn injury.