Comparison of levels of cytochromes P-450, CYP1A2, CYP2E1, and their related monooxygenase activities in human surgical liver samples

Alcohol Clin Exp Res. 1993 Aug;17(4):900-5. doi: 10.1111/j.1530-0277.1993.tb00861.x.


Hepatic microsomal cytochromes P-450 CYP1A2, and CYP2E1 contents and catalytic activities have been simultaneously investigated in 42 patients undergoing diagnostic liver biopsy. CYP1A2 contents, measured by Western blotting, were correlated with methoxyresorufin-O-demethylation and ethoxyresorufin-O-deethylation (r = 0.65 and r = 0.66, p < 0.001, respectively). CYP2E1 contents were correlated with 1-butanol oxidation and 6-hydroxylation of chlorzoxazone (r = 0.75 for both, p < 0.001). CYP1A2 catalytic activities varied by 30- to 40-fold, whereas CYP2E1 activities varied by 6- to 20-fold. In our study, these variations were not related to liver diseases or cancer of the digestive tract nor to alcohol drinking or smoking habits, because patients were alcohol- and tobacco-free for 1 month before the study. Other environmental factors, diet habits, and/or genetic factors could explain the large interindividual variations observed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Cytochrome P-450 CYP1A2
  • Cytochrome P-450 Enzyme System / metabolism*
  • Female
  • Humans
  • Liver / enzymology
  • Liver / pathology*
  • Liver Diseases, Alcoholic / enzymology
  • Liver Diseases, Alcoholic / pathology*
  • Male
  • Middle Aged
  • Oxidoreductases / metabolism*
  • Oxygenases / metabolism*
  • Smoking / adverse effects
  • Smoking / pathology


  • Cytochrome P-450 Enzyme System
  • Oxidoreductases
  • Oxygenases
  • Cytochrome P-450 CYP1A2