The present study was undertaken in an attempt to cmpare sensitivity of mutagenecity
of two kinds of carcinogens: dimethylnitrosamine(DMN), diethylnitrosamine(DEN)on
chromosome level by examining metaphase chromosomal aberrations and sister
chromatid exchanges (SCEs). The five kinds of dosages of DMN and DEN (1×10^(-6),
5×10^(-6), 1×10^(-5), 1×10^(-5), 5×10^(-5) and 1×10^(-4) M) were applied to the
cultured embryonic cells of mouse and the results thus obtained are presented below:
1. The types of chromosome aberrations were found to be mainly chromatid gaps,
chromosome breaks, chromosome exchanges and dicentrics. Chromosomes aberrations
showed increase of frequencies as dosage of carcinogen increased and the total
chromosome aberrations were detected to be higher in DMN than in DEN treatment.
2. Cells treated with only BUdR showed 7.06±0.34/cell of SCEs and cells treated with
DMn and DEN showed increase of 2.14 and 2.06 times of SCE production from BUdR
treated control. respectively. SCE frequencies increased as dosages of carcinogens
increased and it was also shown that DMN treatment produced more SCEs than DEN
did.
3. The SCE test method was manifested to be approximately 15 times more sensitive
then conventional metaphase chromosome aberration score method.
4. The DMN was also found to be more potent agent for inducing chromosome
aberrations and SCEs than DEN.
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