DNA repair synthesis induced by azo dyes in primary rat hepatocyte cultures using the bromodeoxyuridine density-shift method.
The genotoxic activity of the benzeneamine-derived azo dyes, Disperse Red 54 (DR 54), Direct Red 81 (DR 81) and Direct Black 19:1 (DB 19:1) was studied in the in vitro DNA repair assay in primary rat hepatocyte cultures. Hepatocytes were isolated, cultured and treated with the azo dyes, bromodeoxyuridine and [3H] cytidine. DNA repair synthesis was determined as an incorporation of [3H] cytidine into unreplicated DNA strands using the bromodeoxyuridine density-shift method. Of the 3 azo dyes, only DR54 (monoazo dye) induced a weak DNA repair synthesis in rat hepatocytes in vitro. DR81 and DB 19:1 did not induce any concentration-related DNA repair synthesis expressed as cpm/micrograms DNA. The data suggest that the in vivo reduction of azo dyes is required for the genotoxicity of these azo dyes.
Palus
J
J
Department of Carcinogenesis, Teratogenesis and Mutagenesis, Nofer Institute of Occupational Medicine, Lodz, Poland.
Schwarz
L
L
Frank
C
C
Andrae
U
U
D000818:Animals; D001391:Azo Compounds / Q000494:pharmacology*; D001973:Bromodeoxyuridine; D002478:Cells, Cultured; D004396:Coloring Agents / Q000494:pharmacology*; D004260:DNA Repair / Q000187:drug effects* / Q000502:physiology; D008099:Liver / Q000166:cytology; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D001391:Azo Compounds; D004396:Coloring Agents; C096308:disperse red 54; C062246:Direct Red 81; C049357:direct black 19; D001973:Bromodeoxyuridine