title: Methotrexate-leucovorin synchronization of human bone marrow cultures. Induction of high-resolution R- and G-banding.
abstract: Simple R- and G-banding techniques based on a methotrexate S-phase block, released by exposure to leucovorin, were used for preparation of human bone marrow samples. R-bands were induced by adding 5-bromodeoxyuridine and Hoechst 33258 to the cultures, followed by a modified FPG-staining. G-bands were induced by adding ethidium bromide to the cultures, followed by a modified trypsin treatment of the slides. Due to Hoechst 33258 or ethidium bromide exposure prior to harvest chromosome contraction was partly inhibited and well-defined R- or G-banding was observed after appropriate staining in elongated prometaphase chromosomes.
mesh_terms: D001853:Bone Marrow / Q000187:drug effects* / Q000648:ultrastructure; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002478:Cells, Cultured; D002871:Chromosome Banding / Q000379:methods*; D003703:Demecolcine / Q000494:pharmacology; D006801:Humans; D007399:Interphase / Q000187:drug effects; D002955:Leucovorin / Q000494:pharmacology*; D008677:Metaphase / Q000187:drug effects; D008727:Methotrexate / Q000494:pharmacology*; D008938:Mitosis / Q000187:drug effects; D008940:Mitotic Index
chemical_list: D001973:Bromodeoxyuridine; D002955:Leucovorin; D008727:Methotrexate; D003703:Demecolcine