Chernoff G F, Golden J A
Department of Pediatrics, University of California San Diego, La Jolla 92037.
Teratology. 1988 Jan;37(1):37-42. doi: 10.1002/tera.1420370107.
Pregnant LM/Bc female mice were given a 10-minute hyperthermic exposure in a 43 degrees C waterbath during the period of neural tube closure. On day 15.5 of gestation, the females were killed, and the fetuses were examined for exencephaly. Following a single treatment on day 8.0, 8.5, 8.75, or 9.0 of gestation 1.7, 13.6, 2.9, and 0.8% of the respective fetuses displayed exencephaly. With two treatments, one on each of gestational days 8.5 and 8.75, or three treatments, one on each of gestational days 8.5, 8.75, and 9.0, the percentage of exencephalic fetuses increased to 28.3 and 59.3%, respectively. The increased response to multiple treatments was not due to an increase in the number of susceptible embryos but rather was due to the increased number of treatments. The results of this study suggest that with increasing numbers of treatments, the embryo's ability to recover from the hyperthermic exposure is lessened, resulting in an increase in exencephaly.
在神经管闭合期间，将怀孕的LM/Bc雌性小鼠置于43摄氏度的水浴中进行10分钟的热暴露。在妊娠第15.5天，处死雌性小鼠，并检查胎儿是否患有无脑畸形。在妊娠第8.0、8.5、8.75或9.0天进行单次处理后，相应胎儿中分别有1.7%、13.6%、2.9%和0.8%出现无脑畸形。进行两次处理（分别在妊娠第8.5天和8.75天各进行一次）或三次处理（分别在妊娠第8.5天、8.75天和9.0天各进行一次）时，无脑畸形胎儿的百分比分别增至28.3%和59.3%。对多次处理的反应增加并非由于易感胚胎数量增加，而是由于处理次数增加。本研究结果表明，随着处理次数增加，胚胎从热暴露中恢复的能力减弱，导致无脑畸形增加。
