Cell kinetics of mouse urinary bladder epithelium
- 9 Downloads
The initial effect of a single subcutaneous injection of 0.01 ml of dibutylnitrosamine on the mouse (hr/hr strain) urinary bladder epithelium was a block in DNA synthesis in the diploid cells followed by a regenerative reaction. This did not, however, lead to a subsequent wave of increased DNA synthesis among the tetraploid cells.
Later, a new wave of DNA synthesis occurred among the diploid cells, and again there was no subsequent wave of tetraploid DNA synthesis. The total cell number was not affected. These disturbances resulted in periods of reduced numbers of octoploid cells. This effect was unlike that obtained in previously published experiments using cyclophosphamide, which led to considerable hyperplasia, especially of octoploid cells, and no disturbance of tetraploid DNA synthesis.
Thus the action of a single dose of dibutylnitrosamine on the epithelial cells in the mouse urinary bladder is very different from that of cyclophosphamide in a single dose, but it is not possible to say whether this has anything to do with the carcinogenicity of the nitrosamine.
Key wordsUrothelium Polyploidy Dibutylnitrosamine
- Craddock, V.M.: Effect of a single treatment with the alkylating carcinogens dimethylnitrosamine, diethylnitrosamine and methyl methanesulphonate, on liver regenerating after partial hepatectomy. II Alkylation of DNA and inhibition of DNA replication. Chem.-Biol. Interact.10, 323–332 (1975)PubMedCrossRefGoogle Scholar
- Farsund, T.: Preparation of bladder mucosa cells for micro-flow fluorometry. Virchows Arch. B Cell Path.16, 35–42 (1974)Google Scholar
- Farsund, T.: Cell kinetics of mouse urinary bladder epithelium. I. Circadian and age variations in cell proliferation and nuclear DNA content. Virchows Arch. B Cell Path.18, 35–49 (1975)Google Scholar
- Farsund, T.: Cell kinetics of mouse urinary bladder epithelium. II. Changes in proliferation and nuclear DNA content during necrosis, regeneration, and hyperplasia caused by a single dose of cyclophosphamide. Virchows Arch. B Cell Path.21, 279–298 (1976)Google Scholar
- Farsund, T., Dahl, E.: Cell kinetics of mouse urinary bladder epithelium. III. An ultrastructural study of the bladder epithelium during regeneration after a single dose of cyclophosphamide with special reference to the mechanism by which polyploid cells are formed. Virchows Arch. B Cell Path. (Submitted for publication)Google Scholar
- Hard, G.C., Shaw, D.M.: Proliferative response in the rat kidney induced by a single, carcinogenic dose of dimethylnitrosamine. Cell Tiss. Kinet.7, 433–441 (1974)Google Scholar
- Wood, M., Flaks, A., Clayson, D.B.: The carcinogenic activity of dibutylnitrosamine in IF x C57 mice. Europ. J. Cancer6, 433–440 (1970)Google Scholar