Evidence for arrested G2 cell subpopulation in rat liver inducible to mitosis.
The intraperitoneal administration of several substances (biliverdin, heat-killed bacteria and diatomaceous earth) to rats caused the prompt appearance of a mitotic wave in the liver. Autoradiographic analysis of livers of treated animals showed no evidence of [3H]-thymidine uptake by mitotic hepatocytes. In addition, livers from xenobiotic-treated rats showed a very low thymidine kinase activity, close to that found in normal livers. This excludes the possibility that non-cycling cells move to mitosis through the S phase. The results suggest that mitosis could be derived from a hepatocyte subpopulation arrested in the G2 phase of the cell cycle, which is stimulated to divide by the xenobiotics.
D000818:Animals; D001419:Bacteria; D001664:Biliverdine / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D004247:DNA / Q000096:biosynthesis; D006498:Hepatectomy; D007399:Interphase / Q000187:drug effects; D008099:Liver / Q000166:cytology*; D008938:Mitosis; D008940:Mitotic Index / Q000187:drug effects; D051381:Rats; D013937:Thymidine Kinase / Q000378:metabolism; D015262:Xenobiotics / Q000494:pharmacology*
D015262:Xenobiotics; D004247:DNA; D013937:Thymidine Kinase; D001664:Biliverdine