[Experimental study of the time course of DNA strand breaks and DNA synthesis during liver regeneration after partial hepatectomy in rats].
The time course of DNA strand breaks (nicks) and DNA synthesis during liver regeneration were studied in rats with 70% partial hepatectomy. Cellular nicks were detected by in situ nick translation (ISNT) using biotin-labelled mixture and DNA synthesis was assessed by immunohistochemical staining using BrdU and/or PCNA monoclonal antibodies. Nicks appeared on periportal and subcapsular hepatocytes in normal liver tissue, and increased from 24 hours to 48 hours (peak time) after hepatectomy in mainly periportal area. Hepatocytes with BrdU intake increased from 24 hours after hepatectomy with peak value in mainly periportal area. Hepatocytes stained with PCNA antibody increased from 24 hours after hepatectomy in mainly periportal area and there were most positive staining cells at 48 hours after hepatectomy. In liver regeneration after hepatectomy, it apparently suggested that nicks in hepatocytes appeared in G0-G1 phase that was slightly before S phase and after M phase, but almost cells at G0-G1 were not stained, and hepatocytes with PCNA protein appeared following the BrdU intake in the same cells.
Watanabe
M
M
First Department of Surgery, Toho University School of Medicine, Tokyo, Japan.
D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis*; D004264:DNA Topoisomerases, Type I / Q000494:pharmacology; D006498:Hepatectomy; D008115:Liver Regeneration / Q000502:physiology*; D008297:Male; D009687:Nuclear Proteins / Q000032:analysis; D018809:Proliferating Cell Nuclear Antigen; D051381:Rats; D017208:Rats, Wistar
D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D004247:DNA; D004264:DNA Topoisomerases, Type I; D001973:Bromodeoxyuridine