Jensh R P, Brent R L
Proc Soc Exp Biol Med. 1986 Apr;181(4):611-9. doi: 10.3181/00379727-181-42299.
Forty-one pregnant Wistar strain rats were irradiated with 0.6-Gy X rays or were sham irradiated on the 9th or 17th days of gestation to determine if this dosage level would result in alterations in postnatal neurophysiologic development. Half of the mothers were sacrificed at term, and the developmental status of 221 newborns was evaluated. The remaining mothers delivered and raised their litters. The 161 offspring were observed for the age of attainment of the following physiologic parameters: pinna detachment, eye opening, testes opening. Offspring were also tested for the acquisition of the following selected reflexes: surface righting, negative geotaxis, auditory startle, air righting, and visual placing. Term fetal weight was lower than the controls in the group irradiated on the 9th day but was recuperable postnatally. None of the 9 developmental tests performed postnatally were abnormal in the animals irradiated on the 9th day. Thus, at least with regard to these measures, the surviving embryos exposed during the all-or-none period could not be differentiated from the controls. Offspring irradiated on the 17th day exhibited retarded growth which persisted during neonatal life. The three-day-mean neonatal weight was significantly lower in the group irradiated on the 17th day compared to controls. There were no significant maternal body weight or organ/weight differences between the groups. Rats exposed in utero on the 17th day had a significantly delayed acquisition of air righting. These results demonstrate that 0.6-Gy in utero irradiation on the 17th day of gestation can cause subtle alterations in growth and development of the Wistar strain rat during postnatal life.
41只怀孕的Wistar品系大鼠在妊娠第9天或第17天接受0.6戈瑞的X射线照射或假照射，以确定该剂量水平是否会导致出生后神经生理发育的改变。一半的母亲在足月时被处死，对221只新生幼崽的发育状况进行评估。其余的母亲分娩并抚养它们的幼崽。观察161只后代达到以下生理参数的年龄：耳廓分离、睁眼、睾丸下降。还对后代进行以下选定反射的获得测试：表面翻正反射、负趋地性、听觉惊跳反射、空中翻正反射和视觉放置反射。第9天接受照射组的足月胎儿体重低于对照组，但出生后可恢复。第9天接受照射的动物在出生后进行的9项发育测试中均无异常。因此，至少就这些指标而言，在全或无期暴露的存活胚胎与对照组没有差异。第17天接受照射的后代生长迟缓，在新生儿期持续存在。与对照组相比，第17天接受照射组的三日平均新生儿体重显著降低。各组之间母亲的体重或器官/体重没有显著差异。在子宫内第17天接受照射的大鼠空中翻正反射的获得明显延迟。这些结果表明，妊娠第17天子宫内0.6戈瑞的照射可导致Wistar品系大鼠出生后生长发育的细微改变。
