COMPARISON OF BENZO(A)PYRENE METABOLISM IN BRONCHUS, ESOPHAGUS, COLON, AND DUODENUM FROM THE SAME INDIVIDUAL

  • 1 January 1982
    • journal article
    • research article
    • Vol. 42  (3) , 934-938
Abstract
The metabolism of benzo(a)pyrene (BAP) was investigated in cultured normal human bronchus, colon, duodenum and esophagus obtained from the same patient. The highest total metabolism was found in bronchus and duodenum, while the highest mean binding level was observed in the bronchus followed, in order, by the esophagus, duodenum and transverse colon. A 30-fold interindividual variation in the binding level was found in each of the 4 organs studied, and a positive correlation between the binding levels in bronchus, colon and duodenum was found. In human bronchus, a positive correlation was found between level of binding of BAP to DNA and the amount of both benzo(a)pyrene-7,8-diol and the combined group of 3-hydroxybenzo(a)pyrene, BAP 9,10-diol, and water-soluble metabolites. A significantly higher relative amount of BAP tetrols and BAP 9,10-diol was formed by human bronchus compared to the gastrointestinal tissues, while a higher level of BAP phenols was formed by the latter. The relative distribution of BAP-DNA adducts was similar in all four organs, the major DNA adduct being formed by trans-addition of anti-7,8-dihydroxy-9,10-epoxide-7,8,9,10-tetrahydrobenzo(a)pyrene to the 2-amino group at guanine. These results indicate that the metabolism of BAP by at least 4 different organs is qualitatively similar but that quantitative differences exist.