Cytochrome P-450 Content and the Ability of Liver Microsomes From Patients Undergoing Abdominal Surgery to Alter the Mutagenicity of a Primary and a Secondary Carcinogen

The capacity of microsomes isolated from patients undergoing abdominal surgery to alter the mutagenicity of a primary and a secondary carcinogen was investigated and related to the cytochrome P-450 content of the liver. Such microsomes activated the mutagenic effect on bacteria of the secondary carcinogen dimethylnitrosamine and inactivated that of the primary carcinogen N-methyl-N- nitro-N-nitrosoguanidine. The differential ability of microsomes to alter mutagenicity varied in parallel with cytochrome P-450 content. This suggests great variability in the capacity of patients, examined to metabolize carcinogens by their microsomes.