Clastogenic effect of 4-nitroquinoline-1-oxide on swine urothelial cells in culture

Abstract

Swine bladder epithelial cells in culture were treated with 4-nitroquinoline-1-oxide (4NQO) for 4 hr with three different concentrations to examine dose-dependent effects. To study time course effects, they were treated with one concentration for 4 hr and then incubated in 4NQO-free medium for three different periods before harvesting. Three different effects were recorded: (i) a suppression of mitotic activity that was dose-dependent and which continued for more than 30 hr posttreatment; (ii) no marked changes in the proportions of different ploidy classes; and (iii) chromatid gaps, breaks, and exchanges that were dose-dependent. This clastogenic effect decreased with increasing time after treatment.