Abstract
Enlarged hepatocytes with huge nuclei were found in LEC rats with hereditary hepatitis. Flow cytometric analysis of the DNA content of nuclei from jaundiced LEC rats revealed the presence of very high polyploids, such as 32n and 64n. At the age of 12 weeks, before the onset of hepatitis, 8n polyploid nuclei were more frequent in LEC rats than in LEA rats, a sibling line of LEC rats. Binucleated hepatocytes were also more frequent in LEC rats than in LEA rats at week 4. Bi‐, tri‐ and tetra‐nucleated cells whose nuclei were sometimes different in size were observed when jaundice became manifest. The number of proliferating liver cells, determined by pulse labeling with 5‐bromo‐ 2′‐deoxyuridine (BrdU), was higher in LEC rats than in LEA rats at 2, 4, 8, 12 and 14 weeks, with a maximum at week 4. A remarkable increase of BrdU uptake was observed at week 16, when jaundice developed. The possible involvement of abnormal cytokinesis and kariokinesis in the manifestation of hepatitis was suggested.
Keywords: LEC rat, Polyploid, Polynucleated cell
Full Text
The Full Text of this article is available as a PDF (339.4 KB).
REFERENCES
- 1. ) Sasaki , M. , Yoshida , M. C. , Kagami , K. , Takeichi , N. , Kobayashi , H. , Dempo , K. and Mori , M.Spontaneous hepatitis in an inbred strain of Long‐Evans rats, Rat News . Lett. , 14 , 4 – 6 ( 1985. ). [Google Scholar]
- 2. ) Yoshida , M. C. , Masuda , R. , Sasaki , M. , Takeichi , N. , Kobayashi , H. , Dempo , K. and Mori , M.New mutation causing heraditary hepatitis in the laboratory rat . J. Hered. , 78 , 361 – 365 ( 1987. ). [DOI] [PubMed] [Google Scholar]
- 3. ) Masuda , R. , Yoshida , M. C. , Sasaki , M. , Dempo , K , and Mori , M.High susceptibility to hepatocellular carcinoma development in LEG rats with hereditary hepatitis . Jpn. J. Cancer Res. , 79 , 828 – 835 ( 1988. ). [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4. ) Masuda , R. , Yoshida , M. C. , Sasaki , M. , Dempo , K. and Mori , M.Hereditary hepatitis in the LEC rat strain controlled by a single autosomal recessive gene . Lab. Anim. , 22 , 166 – 169 ( 1988. ). [DOI] [PubMed] [Google Scholar]
- 5. ) Berry , M. N. and Friend , D. S.High‐yield preparation of isolated rat liver parenchymal cells . J. Cell Biol. , 43 , 506 – 520 ( 1969. ). [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6. ) Vindeløv , L. L. , Christensen , I. J. and Nissen , N. I.A detergent‐trypsin method for the preparation of nuclei for flow cytometric DNA analysis . Cytometry , 3 , 323 – 327 ( 1983. ). [DOI] [PubMed] [Google Scholar]
- 7. ) Takahashi , H. , Oyamada , M. , Fujimoto , Y. , Satoh , M. I. , Hattori , A. , Dempo , K. , Mori , M. , Tanaka , T. , Watabe , H. , Masuda , R. and Yoshida , M. C.Elevation of serum alpha‐fetoprotein and proliferation of oval cells in the livers of LEC rats . Jpn. J. Cancer Res. , 79 , 821 – 827 ( 1988. ). [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8. ) Naora , H.Microspectrophotometry of cell nuclei stained with the Feulgen reaction. IV. Formation of tetraploid nuclei in rat liver cells during postnatal growth . J. Biophys. Biachem. Cytol. , 3 , 949 – 975 ( 1957. ). [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9. ) Alfert , M. and Geschwind , I. I.The development of polysomaty in rat liver . Exp. Cell Res. , 230 – 232 ( 1985. ). [DOI] [PubMed] [Google Scholar]
- 10. ) Nadal , C. and Zajdela , F.Polyploidie somatique dans le foie derat. I. Le role des cellules binuclees dans la genese des cellules polyploides . Exp. Cell Res. , 42 , 99 – 116 ( 1966. ). [DOI] [PubMed] [Google Scholar]
- 11. ) Epstein , C. J.Cell size, nuclear content, and the development of polyploidy in the mammalian liver . Proc. Natl. Acad. Sri. USA , 57 , 327 – 334 ( 1967. ). [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12. ) Grisham , J. W.Cellular proliferation in the liver . In “ Normal and Malignant Cell Growth , Vol. 17 ,” ed. Fry P. J. M. , Griem M. L. and Kirsteu W. H. , pp. 28 – 43 ( 1969. ). Springer; , Berlin . [Google Scholar]
- 13. ) Roszell , J. A. , Fredi , J. L. and Irving , C. C.The development of polyploidy in two classes of rat liver nuclei . Biochim. Biophys. Acta. 519 , 306 – 316 ( 1978. ). [DOI] [PubMed] [Google Scholar]
- 14. ) Steele , P. R. M. , Yim , A. P. C. , Herbertson , B. M. and Watson , J.Some cytofluorimetric studies of the nuclear ploidy of mouse hepatocytes. I. A simple method for isolation of hepatocyte nuclei using in situ perfusion of the liver . Br. J. Exp. Pathol. , 62 , 469 – 473 ( 1981. ). [PMC free article] [PubMed] [Google Scholar]
- 15. ) Styles , J. , Elliott , B. M. , Lefevre , P. A. , Robinson , M. , Pritchard , N. , Hart , D. and Ashby , J.Irreversible depression in the ratio of tetraploid:diploid liver in rats treated with 3′‐methyl‐4‐dimethylaminoazobenzene (3′M) . Carcinogenesis , 6 , 21 – 28 ( 1985. ). [DOI] [PubMed] [Google Scholar]
- 16. ) Danielsen , H. E. , Steen , H. B. , Lindmo , T. and Refth , A.Ploidy distribution in experimental liver carcinogenesis in mice . Carcinogenesis , 9 , 59 – 63 ( 1988. ). [DOI] [PubMed] [Google Scholar]
- 17. ) St Aubin , P. M. G. and Bucher , N. L. R.A study of binucleate cell counts in resting and regenerating rat liver employing a mechanical method for the separation of liver cells . Anat. Rec. , 112 , 797 – 809 ( 1952. ). [DOI] [PubMed] [Google Scholar]
- 18. ) Wheatley , D. N.Binucleation in mammalian liver . Exp. Cell. Res. , 74 , 455 – 465 ( 1972. ). [DOI] [PubMed] [Google Scholar]
- 19. ) Geshwind , I. I. , Alfert , M. and Schooley , C.Liver regeneration and hepatic polyploidy in the hypophysectomized rat . Exp. Cell. Res. , 15 , 232 – 235 ( 1958. ). [DOI] [PubMed] [Google Scholar]
- 20. ) Wiest , L.The effect of diethylnitrosamine on the distribution of cell classes in the parenchyma of the liver of newborn rats . Eur. J. Cancer , 8 , 121 – 125 ( 1972. ). [DOI] [PubMed] [Google Scholar]
- 21. ) Nakanishi , K. and Fujita , S.Molecular mechanism of polyploidization and binucleate formulation of hepatocyte . Cell Struct. Funct. , 2 , 261 – 265 ( 1977. ). [Google Scholar]
- 22. ) Wanson , J. C. , Bernaert , D. , Penasse , W. , Mosselmans , R. and Bammasch , P.Separation in distinct subpopulations by elutriation of liver cells following exposure of rats to N‐nitrosomorpholine . Cancer Res. , 40 , 459 – 471 ( 1980. ). [PubMed] [Google Scholar]
- 23. ) Bohm , N. and Noltemeyer , N.Excessive reversible phenobarbital induced nuclear DNA‐polyploidization in the growing mouse liver . Histochemistry , 72 , 63 – 74 ( 1981. ). [DOI] [PubMed] [Google Scholar]
- 24. ) Romagna , F. and Zbinden , G.Distribution of nuclear size and DNA content in serial liver biopsies of rats treated with N‐nitrosomorpholine, phenobarbital and butylated hydroxytoluene . Exp. Cell Biol. , 49 , 294 – 305 ( 1981. ). [DOI] [PubMed] [Google Scholar]
- 25. ) Digernes , V.Chemical liver carcinogenesis: monitoring of the process by flow cytometric DNA measurements . Environ. Health Perspect. , 50 , 195 – 200 ( 1983. ). [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26. ) Brodsky , W. Y. and Uryvaeva , I. V.Cell polyploidy: its relation to tissue growth and function . Int. Rev. Cytol. , 50 , 275 – 332 ( 1977. ). [DOI] [PubMed] [Google Scholar]
- 27. ) LeBouton , A. V.DNA synthesis and cell proliferation in the simple liver acinus of 10‐ to 20‐day‐old rats: evidence for cell fusion . Anal Rec. , 184 , 679 – 688 ( 1976. ). [DOI] [PubMed] [Google Scholar]
- 28. ) Majno , G. , LaGattuta , M. and Thompson , T. E.Cellular death and necrosis; chemical, physical and morphologic changes in rat liver . Virchows Arch. Pathol. Anat. Physiol , 222 , 421 – 465 ( 1960. ). [DOI] [PubMed] [Google Scholar]
- 29. ) Trump , B. F. and Arstila , A. U.Cell membranes and disease processes . In “ Pathobiology of Cell Membranes , Vol. 1 ,” ed. Trump B. F. and Aristila A.U. , pp. 1 – 103 ( 1975. ). Academic Press; , New York . [Google Scholar]