[Comparative studies of cytokinesis-block and conventional micronucleus test in human lymphocytes cultured in vitro. II. Genotoxicological effects of mitomycin C].
The authors have studied genotoxicological effects of MMC by means of CB- and C-MNT to evaluate practical value of CB-MNT. The main results are as follows: (1) In 0.025-0.4 microgram/ml of MMC MNFs in lymphocytes detected by CB- and C-MNT presented dose-dependent increase, but the MNT detected by C-MNT was higher than that by CB-MNT, this difference became greater as MMC concentrations were increased. The minimum concentrations were 0.1 microgram/ml for CB-MNT and 0.025 microgram/ml for C-MNT respectively. Therefore C-MNT is more sensitive to MMC than to CB-MNT; (2) The mean volume of MN detected by CB- and C-MNT was estimated separately. The volume of MN detected by CB-MNT was about 3 times as large as that by C-MNT. The authors suggested that the fusion between micronuclei in cytoplasm of CB- cells could lead to increase of MN volume and decrease of MN numbers; (3) In healthy donors the background MNF in lymphocytes detected by CB-MNT was significantly higher than that by C-MNT, it could be one of the reasons that led to the decrease of the sensitivity of CB-MNT to low doses of mutagens. Finally, the practical value of CB- and C-MNT was discussed.
Xue
K X
KX
Cancer Institute of Jiangsu Province, Nanjing.
Shen
Z L
ZL
Ma
G J
GJ
D000328:Adult; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D015162:Micronucleus Tests; D008875:Middle Aged; D016685:Mitomycin / Q000633:toxicity*
D016685:Mitomycin