Bulman-Fleming B, Wahlsten D
Department of Psychology, University of Waterloo, Ontario, Canada.
Exp Neurol. 1988 Mar;99(3):636-46. doi: 10.1016/0014-4886(88)90180-x.
The corpus callosum of many but not all BALB/c mice is either abnormally small or absent. The basis for the defect is hereditary, but the proportion of mice expressing the anomaly can be modified by changing the early environment. The present study investigated the effects of an F1 hybrid maternal environment, which is known to promote better fetal development than an inbred environment, on body and brain growth in BALB/c and on the incidence of the corpus callosal defect. Ovarian follicle cells from BALB/cWah (albino) mice were grafted into pigmented F1 hybrid, BALB/cWah, and pigmented BALB female hosts of comparable age which were subsequently mated to BALB/cWah males. Groups of unoperated BALB/cWah and pigmented BALB dams were included as controls. Data from 111 litters were analyzed. Results showed that BALB mice with F1 mothers had heavier bodies at birth, weaning, and 100 days of age and heavier brains at 100 days than those with either grafted or ungrafted BALB mothers. The effects at birth were evident across all litter sizes (2 to 11), but those at weaning and 100 days were seen only in litters of more than 5 or 6. Neither the F1 hybrid maternal environment nor the grafting procedure itself appeared to influence the incidence or expression of the corpus callosal defect. About 22% of the offspring from each of the three groups (ungrafted BALB, grafted BALB, and grafted F1) showed a defective corpus callosum.
许多（但并非所有）BALB/c小鼠的胼胝体要么异常小，要么缺失。这种缺陷的基础是遗传性的，但表达这种异常的小鼠比例可通过改变早期环境来调节。本研究调查了已知比近交环境更有利于胎儿发育的F1杂种母体环境对BALB/c小鼠身体和大脑生长以及胼胝体缺陷发生率的影响。将来自BALB/cWah（白化）小鼠的卵巢卵泡细胞移植到年龄相当的有色F1杂种、BALB/cWah和有色BALB雌性宿主中，随后将它们与BALB/cWah雄性小鼠交配。将未手术的BALB/cWah和有色BALB母鼠组作为对照。分析了来自111窝的数据。结果显示，与有移植或未移植BALB母鼠的BALB小鼠相比，有F1母鼠的BALB小鼠在出生、断奶和100日龄时体重更重，在100日龄时大脑更重。出生时的影响在所有窝仔数（2至11只）中都很明显，但断奶和100日龄时的影响仅在超过5或6只的窝仔中出现。F1杂种母体环境和移植过程本身似乎都不影响胼胝体缺陷的发生率或表现。三组（未移植BALB、移植BALB和移植F1）中每组约22%的后代显示胼胝体有缺陷。
