Japanese Journal of Veterinary Research;Volume 53, Number 3-4


Analysis of the cell cycle of fibroblasts derived from the LEC rat after X-irradiation

Masuda, Kazuhiko;Miyamoto, Tomomi;Cho, A-Ri;Agui, Takashi

Permalink : http://hdl.handle.net/2115/5906
JaLCDOI : 10.14943/jjvr.53.3-4.141
KEYWORDS : Cell cycle;Fibroblast;LEC rat;X-irradiation;X-ray hypersensitivity


The LEC rat is reported to exhibit hypersensitivity to X-irradiation, deficiency in DNA double-strand break repair, and radio-resistant DNA synthesis. This character of the LEC rat has been thought to be due to abnormal G1arrest in cells after X-irradiation. In this report, we re-investigated the effect of X-irradiation on the cell cycle in primary-cultured fibroblasts . Primarycultured fibroblasts derived from LEC and BN rats were exposed to4Gy of Xray and their cell cycle analysis was performed with a flow cytometer. Fibroblasts derived from both rats showed normal response of the cell cycle, indicating the arrest at both G1‐and G2/M-phase and no difference in the cell cycle population between fibroblasts derived from both rats. In contrast, when the same analysis was performed using the cell line, L7and W8,which had been established from the lung fibroblasts of LEC and control WKAH rats, respectively, by immortalizing with SV40T-antigen, L7cells but not W8cells showed impaired G1arrest and abnormal cell cycle. These results suggest that fibroblasts derived from LEC rats possess the normal cell cycle response after Xirradiation, if they are kept naive as not immortalized with SV40T-antigen.