Universidad de Oviedo.
Psicothema. 2019 Feb;31(1):46-52. doi: 10.7334/psicothema2018.290.
Exposure to maternal separation (MS) in rodents may have long-lasting consequences for the structure and function of several brain regions, eventually associated with alterations in cognition and emotion later in life. Post-weaning environmental enrichment (EE) has been reported to ameliorate the detrimental effects of exposure to early life stress mainly in the hippocampus.
In vivo magnetic resonance imaging (MRI) was applied to evaluate possible volumetric changes in the dorsal and ventral hippocampus, the medial prefrontal cortex and the dorsal striatum of 90-day-old male rats after daily MS for 240 min from postnatal days 2-21.
No significant volume changes were found in the selected brain regions in MS animals as compared with an age-matched control group. However, additional groups of control and MS animals with EE from days 21-60 showed significant volume increases in the medial prefrontal cortex and the ventral hippocampus as compared to the groups without EE. In addition, general hemispheric asymmetry was found in the volume of the brain regions measured.
Our results demonstrate that EE could have differential effects depending on previous exposure to MS and on the development of brain lateralization.
在啮齿动物中，母体分离（MS）暴露可能对几个大脑区域的结构和功能产生持久影响，最终与生命后期的认知和情绪改变相关。据报道，新生后环境丰富（EE）可改善早期生活应激暴露的有害影响，主要在海马体中。
应用活体磁共振成像（MRI）评估 90 日龄雄性大鼠在出生后第 2-21 天每天接受 240 分钟 MS 后，其背侧和腹侧海马体、内侧前额叶皮质和背侧纹状体的可能体积变化。
与年龄匹配的对照组相比，MS 动物在选定的大脑区域中未发现明显的体积变化。然而，从第 21-60 天开始有 EE 的额外对照组和 MS 动物组与无 EE 的组相比，内侧前额叶皮质和腹侧海马体的体积明显增加。此外，还发现了所测量的大脑区域的总体半球不对称性。
我们的结果表明，EE 的影响可能因之前的 MS 暴露以及大脑侧化的发展而有所不同。
