title: Autoradiographic detection of 6-thioguanine-resistant lymphocytes of mice. A novel system in somatic mutagenesis testing.
abstract: After treatment of mice with ethylnitrosourea in vivo, induction of 6-thioguanine-resistant splenic lymphocytes was measured in vitro. The lymphocytes were mitogen-stimulated in presence of thioguanine. After a culture period of 30 h, TG resistance was determined by the ability of cells to incorporate [3H]thymidine. The results suggest that at this selection condition the majority of resistant cells stem from somatic mutations. Thus, the system is potentially useful as a screening assay for somatic mutagenesis testing. The problem of misleading results due to the presence of phenocopies was investigated by treatment in vitro with UV radiation or ethylnitrosourea.
mesh_terms: D000818:Animals; D001345:Autoradiography; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005038:Ethylnitrosourea / Q000494:pharmacology; D008214:Lymphocytes / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D009152:Mutagenicity Tests; D012854:Sister Chromatid Exchange / Q000187:drug effects; D013866:Thioguanine / Q000494:pharmacology*
chemical_list: D013866:Thioguanine; D005038:Ethylnitrosourea