ON THE MECHANISM OF NITROHETEROCYCLIC COM POUNDS (NHCC) METABOLIC DENITRATION (MD)

It has been found that denitration of nitroheterocyclic drugs (NHCC) i n mouse liver homogenate is one of the pathways of their biotransforma tion. This process is accompanied by the release of NO and NO-heme iro n complex formation. The yield of complex increases linearily with tim e of NHCC incubation with liver homogenate and depends on NHCC structu re. The ESR spectrum of the complex represents a superposition of spec tra of NO with hemoglobin and NO with the other heme-containing protei ns. NHCC denitration is inhibited by metyrapone, witch is an evidence of cytochrome P-450 involvement in their metabolic denitration.