Ishikawa H, Endo A
Department of Hygiene and Preventive Medicine, Yamagata University School of Medicine, Japan.
Reprod Toxicol. 1998 Mar-Apr;12(2):115-8. doi: 10.1016/s0890-6238(97)00125-1.
A high incidence of chromosomal anomalies has been observed in the offspring of our XO mouse colony. However, the reason(s) are unknown. We hypothesized that XO dams might be more susceptible to certain chromosomal mutagens. Therefore, we assessed whether the oocytes of XO mice are more susceptible to colchicine. Pregnant XO and XX mice were intraperitoneally (i.p.) injected with colchicine, 0.2 mg/kg, 6 h after mating (between resumption of meiosis II and extrusion of the second polar body). Contrary to our expectation, the incidence of chromosomal anomalies induced by colchicine exposure did not differ between XX and XO dams. These findings suggest that the chromosomal stability of the oocytes from XO mice may not be affected by colchicine exposure at the stage of extrusion of the second polar body. The effects of chromosomal imbalance inherent in XO mice on chemical susceptibilities should be further investigated.
在我们的XO小鼠群体的后代中观察到染色体异常的高发生率。然而，原因尚不清楚。我们推测XO母鼠可能对某些染色体诱变剂更敏感。因此，我们评估了XO小鼠的卵母细胞是否对秋水仙碱更敏感。怀孕的XO和XX小鼠在交配后6小时（减数分裂II恢复到第二极体排出之间）腹腔注射0.2mg/kg秋水仙碱。与我们的预期相反，秋水仙碱暴露诱导的染色体异常发生率在XX和XO母鼠之间没有差异。这些发现表明，在第二极体排出阶段，秋水仙碱暴露可能不会影响XO小鼠卵母细胞的染色体稳定性。应进一步研究XO小鼠固有的染色体失衡对化学敏感性的影响。
