title: In vivo formation of sigma-methyl- and sigma-phenyl-ferric complexes of hemoglobin and liver-cytochrome P-450 upon treatment of rats with methyl- and phenylhydrazine.
abstract: Ferric sigma-phenyl complexes of hemoglobin and liver cytochrome P-450 are formed in vivo upon administration of C6H5NHNH2 to rats. Small amounts of the sigma-methyl complex of hemoglobin were also detected in vivo upon treatment of rats with CH3NHNH2. At the doses used for CH3NHNH2 (25 and 50 mg/kg) the states and levels of hemoglobin in the blood and spleen, and of cytochrome P-450 in the liver were almost unchanged. On the contrary, C6H5NHNH2 (25-100 mg/kg) led to a decrease of the HbO2 blood level (10-50%), together with an increase in the HbFe(III) level and the appearance of the HbFe(III)-C6H5 complex. The concentration of this complex reaches its maximum value (2 mM) 1 h after C6H5NHNH2 administration (20% of total hemoglobin). At the same time large amounts of HbO2, HbFe(III) and HbFe(III)-C6H5 appeared in the spleen, and remained high up to 24 h after treatment. Treatment of rats with C6H5NHNH2 (25-100 mg/kg) led to a significant decrease in the level of liver cytochrome P-450 (a 70% decrease 2 h after treatment with 100 mg/kg C6H5NHNH2). About 15% of the remaining cytochrome P-450 existed as a cyt.-P-450-Fe(III)-C6H5 complex, a new example of cytochrome P-450-Fe-metabolite complex which is stable in vivo.
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D006454:Hemoglobins / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008297:Male; D008763:Methylhydrazines / Q000378:metabolism*; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D009002:Monomethylhydrazine / Q000378:metabolism* / Q000494:pharmacology; D010634:Phenobarbital / Q000494:pharmacology; D010659:Phenylhydrazines / Q000378:metabolism* / Q000494:pharmacology; D011485:Protein Binding; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D006454:Hemoglobins; D008763:Methylhydrazines; D010659:Phenylhydrazines; C030299:phenylhydrazine; D003577:Cytochrome P-450 Enzyme System; D009002:Monomethylhydrazine; D010634:Phenobarbital