Bredy Timothy W, Grant Rebecca J, Champagne Danielle L, Meaney Michael J
Developmental Neuroendocrinology Laboratory and McGill Program for the Study of Behaviour, Genes and Environment, Douglas Hospital Research Centre, 6875 Boul. LaSalle Blvd, Montréal, Canada, H4H 1R3.
Eur J Neurosci. 2003 Nov;18(10):2903-9. doi: 10.1111/j.1460-9568.2003.02965.x.
Maternal care during the first week of postnatal life influences hippocampal development and function (Liu et al., 2000; Nature Neurosci., 3, 799-806). Offspring reared by mothers who exhibit increased levels of pup licking/grooming (LG) show increased hippocampal synaptic density and enhanced spatial learning and memory. Using 5-bromo-2'-deoxyuridine (BrdU), a thymidine analogue incorporated into cells during DNA synthesis, we examined the effects of early maternal care on hippocampal cell proliferation and neuronal survival in the rat. Twenty-four hours following injection on day 7 of life (P7) there were no differences in BrdU labelling in the offspring of high- compared with low-LG mothers, suggesting no maternal effect on the rate of proliferation at this age. However, 14 and 83 days following injection (P21 and P90), the offspring of high-LG mothers had significantly more surviving BrdU-labelled cells and BrdU-NeuN+-colabelled neurons in the dentate gyrus subgranular zone and granule cell layer. At P21, the offspring of high-LG mothers showed increased protein expression of basic fibroblast growth factor and significantly decreased levels of pyknosis. These findings suggest an influence of maternal care on neuronal survival in the hippocampus. Conversely, at the same time point there was a significantly higher level of hippocampal glial fibrillary acidic protein expression in the offspring of low-LG mothers. These findings emphasize the importance of early maternal care for hippocampal development.
产后第一周的母性照料会影响海马体的发育和功能（Liu等人，2000年；《自然神经科学》，第3卷，第799 - 806页）。由表现出较高舔舐/梳理幼崽（LG）水平的母亲抚养的后代，海马体突触密度增加，空间学习和记忆能力增强。我们使用5-溴-2'-脱氧尿苷（BrdU），一种在DNA合成过程中掺入细胞的胸腺嘧啶类似物，来研究早期母性照料对大鼠海马体细胞增殖和神经元存活的影响。在出生后第7天（P7）注射24小时后，高LG组母亲的后代与低LG组母亲的后代在BrdU标记上没有差异，这表明在这个年龄段母性对增殖速率没有影响。然而，在注射后14天和83天（P21和P90），高LG组母亲的后代在齿状回颗粒下区和颗粒细胞层中有显著更多存活的BrdU标记细胞和BrdU-NeuN + 双标记神经元。在P21时，高LG组母亲的后代显示碱性成纤维细胞生长因子的蛋白表达增加，核固缩水平显著降低。这些发现表明母性照料对海马体神经元存活有影响。相反，在同一时间点，低LG组母亲的后代海马体胶质纤维酸性蛋白表达水平显著更高。这些发现强调了早期母性照料对海马体发育的重要性。
