Goldstein L S
Department of Radiation Oncology, University of California, San Francisco 94143.
Radiat Res. 1987 Nov;112(2):374-80.
Female mice were X-irradiated with 0.5-4.5 Gy 2 h before mating to unirradiated males of the same strain. The dominant lethal frequencies (DLF) were determined by growing the embryos in vitro from the two-cell stage and determining the relative rates of successful embryogenesis to the blastocyst stage and to the trophectoderm outgrowth with proliferated inner cell mass stage. The DLF increased with increasing dose, the two linear aspects having a breakpoint at about 1.5 Gy. The nature of embryo failure was also dose dependent. At doses less than 2.0 Gy embryos failed predominantly after blastocyst formation, but at higher doses the embryos failed both before and after blastocyst formation. Over the dose range tested, the frequency with which lesions leading to dominant lethality were induced [i.e., -ln(1 - DLF)] increased linearly with increasing dose.
雌性小鼠在与同品系未受照射的雄性小鼠交配前2小时接受0.5 - 4.5 Gy的X射线照射。通过从二细胞阶段开始体外培养胚胎，并确定成功胚胎发育至囊胚阶段以及至滋养外胚层生长并伴有增殖内细胞团阶段的相对速率，来测定显性致死频率（DLF）。DLF随剂量增加而增加，两个线性部分在约1.5 Gy处有一个断点。胚胎失败的性质也取决于剂量。在小于2.0 Gy的剂量下，胚胎主要在囊胚形成后失败，但在较高剂量下，胚胎在囊胚形成前后均会失败。在所测试的剂量范围内，导致显性致死的损伤诱导频率[即 -ln(1 - DLF)]随剂量增加呈线性增加。
