Zusammenfassung
Von unbehandelten oder für 3 Wochen mit Äthanol vorbehandelten männlichen und weiblichen Ratten wurden Lebermikrosomen isoliert und mit dimethylnitrosamin (DMN) und einem NADPH regenerierenden System inkubiert. Die Vorbehandlung mit Äthanol führte zu einer starken Steigerung der Formaldehyd- und Nitritbildung sowie der Alkylierung mikrosomaler Proteine speziell im niedrigen DMN Dosisbereich. Im Gegensatz hierzu wurde bei in vitro Zugabe von Äthanol oder Tetrahydrofuran der mikrosomale metabolismus von DMN gehemmt.
Summary
Rat liver microsomes were prepared from male and female controls and from animals pretreated for 3 weeks with ethanol, and incubated with dimethylnitrosamine (DMN) and an NADPH-regenerating system. The formation of formaldehyde and nitrite as well as the alkylation of microsomal protein were found to be greatly enhanced, especially in the low DMN concentration range, as a result of long-term ethanol induction. In contrast, ethanol or tetrahydrofuran, when incubated simultaneously with DMN, inhibited microsomal metabolism of the carcinogen.
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Abbreviations
- DMN:
-
dimethylnitrosamine
- DEN:
-
diethylnitrosamine
- cyt. P-450:
-
cytochrome P-450
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Schwarz, M., Appel, K.E., Schrenk, D. et al. Effect of ethanol on microsomal metabolism of dimethylnitrosamine. J Cancer Res Clin Oncol 97, 233–240 (1980). https://doi.org/10.1007/BF00405774
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DOI: https://doi.org/10.1007/BF00405774