Hayashi M, Endoh D, Kon Y, Yamashita T, Hashimoto N, Sato F, Kasai N, Namioka S
Department of Laboratory Animal Science, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
J Vet Med Sci. 1992 Apr;54(2):269-73. doi: 10.1292/jvms.54.269.
LEC strain rats (LEC rats), which have been known to develop hereditarily spontaneous fulminant hepatitis 4-5 months after birth, were highly sensitive to whole-body X-irradiation as compared to WKAH strain rats (WKAH rats). Radiation-induced acute intestinal death occurred at doses higher than 6.5 Gy in LEC rats, and at doses higher than 12.8 Gy in WKAH rats, respectively. By the probit analysis of survival data, it was shown that the LD50/7 value of LEC rats was estimated to be 7.03 Gy which was significantly lower than that (12.99 Gy) of WKAH rats. Histopathological examinations of small intestines from LEC rats 2 days after irradiation at the dose of 8.5 Gy showed severe epithelial death together with edema, whereas little or no significant changes were noted in intestinal epithelium of 8.5 Gy-irradiated WKAH rats. These results suggest that the radiosensitivity of LEC rats to ionizing radiation appears to be higher than that of other strains of rats.
已知LEC品系大鼠（LEC大鼠）在出生后4 - 5个月会发生遗传性自发性暴发性肝炎，与WKAH品系大鼠（WKAH大鼠）相比，它们对全身X射线照射高度敏感。辐射诱导的急性肠道死亡分别发生在LEC大鼠剂量高于6.5 Gy时，以及WKAH大鼠剂量高于12.8 Gy时。通过对生存数据的概率分析表明，LEC大鼠的LD50/7值估计为7.03 Gy，显著低于WKAH大鼠的（12.99 Gy）。对接受8.5 Gy照射后2天的LEC大鼠小肠进行组织病理学检查，结果显示严重的上皮细胞死亡并伴有水肿，而接受8.5 Gy照射的WKAH大鼠肠上皮几乎没有明显变化。这些结果表明，LEC大鼠对电离辐射的放射敏感性似乎高于其他品系的大鼠。
