Dose Response for Benzo(a)pyrene Adducts in Mouse Epidermal DNA1
نویسندگان
چکیده
The dose dependency of the binding of benzo(a)pyrene (BaP) with DNA of mouse epidermis was investigated. BaP conjugated epidermab DNA was isolated and enzymatically degraded to deoxyribonucleosides. The BaP-DNA adducts were separated by Sephadex LH-20 column or high-perform ance liquid chromatography. Two major BaP-DNA adducts were found. One was in the region of the ebution profile that contained polycyclic aromatic hydrocarbons adducted to de oxyribonucleosides. The other adduct was eluted from Seph adex LH-20 and high-performance liquid chromatography cob umns before the deoxyribonucleosides and after deoxyribo nucleotides. Both adducts of BaP in epidermal DNA reached a maximum 7 hr after a single skin application, and subsequently little, if any, loss of adducts was observed for 49 hr. Both adducts varied as a linear function for topical doses in the range from 0.01 to 300 pig/mouse. The formation of DNA adducts by BaP occurred in proportion to dose at doses several orders of magnitude below those that are feasible to test for carcinogenicity.
منابع مشابه
Dose response for benzo(a)pyrene adducts in mouse epidermal DNA.
The dose dependency of the binding of benzo(a)pyrene (BaP) with DNA of mouse epidermis was investigated. BaP-conjugated epidermal DNA was isolated and enzymatically degraded to deoxyribonucleosides. The BaP-DNA adducts were separated by Sephadex LH-20 column or high-performance liquid chromatography. Two major BaP-DNA adducts were found. One was in the region of the elution profile that contain...
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