title: Effects of Hoechst 33258 on human leukocytes in vitro.
abstract: The benzimidazole derivative Hoechst 33258 was added at various concentrations to human leukocyte cultures. After 16 or 24 h of treatment, with concentrations equal to or greater than 100 mug/ml of Hoechst 33258, a number of chromosomes showed regions in which the chromatin was undercontracted. The centromeric regions of chromosome 1 and, more rarely, of chromosomes 3 and 9 appeared to be decondensed. Short decondensed regions were also present on the long arms of chromosomes 1 and 2. The possible nature of these regions is discussed.
mesh_terms: D001562:Benzimidazoles / Q000494:pharmacology*; D006690:Bisbenzimidazole / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002875:Chromosomes / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007962:Leukocytes / Q000187:drug effects* / Q000648:ultrastructure; D008297:Male; D008938:Mitosis / Q000187:drug effects
chemical_list: D001562:Benzimidazoles; D006690:Bisbenzimidazole