Department of Psychology, Cornell University, Ithaca, NY 14853, USA.
Proc Biol Sci. 2012 Feb 22;279(1729):759-66. doi: 10.1098/rspb.2011.1265. Epub 2011 Jul 20.
Early-life stress caused by the deprivation of maternal care has been shown to have long-lasting effects on the hypothalamic-pituitary-adrenal (HPA) axis in offspring of uniparental mammalian species. We asked if deprivation of maternal care in biparental species alters stress responsiveness of offspring, using a biparental avian species--the zebra finch, Taeniopygia guttata. In our experiment, one group of birds was raised by both male and female parents (control), and another was raised by males alone (maternally deprived). During adulthood, offspring of both groups were subjected to two stressors (restraint and isolation), and corticosterone concentrations were measured. Additionally, we measured baseline levels of the two corticosteroid receptors--glucocorticoid receptor (GR) and mineralocorticoid receptor (MR)--in the hippocampus, hypothalamus and cerebellum. Our results suggest that maternally deprived offspring are hyper-responsive to isolation in comparison with controls. Furthermore, mRNA levels of both GR and MR receptors are altered in maternally deprived offspring in comparison with controls. Thus, absence of maternal care has lasting consequences for HPA function in a biparental species where paternal care is available.
早期生活压力，如母婴分离，会对单双亲哺乳动物后代的下丘脑-垂体-肾上腺（HPA）轴产生持久影响。我们通过双亲性鸟类物种-斑胸草雀，探讨了母婴分离是否会改变后代对应激的反应。在我们的实验中，一组雏鸟由雌雄亲鸟共同抚养（对照组），另一组由雄性单独抚养（母婴分离组）。在成年期，两组雏鸟都经历了两种应激源（束缚和隔离），并测量了皮质酮浓度。此外，我们还测量了海马体、下丘脑和小脑内两种糖皮质激素受体（GR）和盐皮质激素受体（MR）的基线水平。结果表明，与对照组相比，母婴分离组的雏鸟对隔离更敏感。此外，与对照组相比，母婴分离组的 GR 和 MR 受体的 mRNA 水平也发生了改变。因此，在有父代照顾的双亲性物种中，母婴分离对 HPA 功能具有持久的影响。
