title: [Early changes in liver chromatin in response to partial hepatectomy].
abstract: Guinea-pig and mouse liver chromatin responds to the partial hepatectomy by an increase in binding of a basic dye acridine orange (AO) and by a decrease of its stability to heat in thermal denaturation test in situ. Degree of the changes in AO chromatin binding is identical in the cells of different ploidy and proportional to their DNA content. Treatment of the preparations by 0.6 M NaCl solutions under conditions bringing about the selective removal of histone H1 from the cells produces in vitro changes in DNA properties taking place in cells in vivo in the course of their activation. The treatment of cells with 0.35 M NaCl solution results in the disappearance of changes occurring in the chromatin of activated cells whereas the properties of control cells remain unchanged. The data obtained are interpreted as a result of the removal of some non-histone regulatory proteins from the chromatin of activated cells that is accompanied by changes in the character of DNA-histone interaction. At the time of maximum increase of AO binding a significant intensification of endogenous RNA polymerase activity was found, the incorporation of [3H] UTP in the nucleolus being higher than that in the extranucleolar part of the nucleus. High ionic strength in the incubation medium (0.4 M (NH4)2SO4) results in drastic increase of radioactive label in the nucleus and in the disappearance of differences between activated and non-activated chromatin. It is concluded that the intensification of RNA synthesis under the influence of proliferative stimulus is more likely dependent on the additional opening of DNA-matrix than on the direct activation of the enzyme.
mesh_terms: D000818:Animals; D002843:Chromatin / Q000378:metabolism* / Q000648:ultrastructure; D004247:DNA / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D006168:Guinea Pigs; D006498:Hepatectomy; D006657:Histones / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008115:Liver Regeneration; D008854:Microscopy, Electron; D009994:Osmolar Concentration; D011485:Protein Binding; D013045:Species Specificity
chemical_list: D002843:Chromatin; D006657:Histones; D004247:DNA; D012321:DNA-Directed RNA Polymerases
vernacular_title: Izmeneniia svoĭstv khromatina kletok pecheni v rannie sroki posle chastichnoĭ gepatektomii