Laboratory of Neuroscience, Faculty of Psychology, Plaza Feijoo s/n Oviedo, Principado de Asturias 33003, Spain; Institute of Neuroscience of Principado Asturias, INEUROPA, Plaza Feijoo s/n Oviedo, Principado de Asturias 33003, Spain.
Laboratory of Neuroscience, Faculty of Psychology, Plaza Feijoo s/n Oviedo, Principado de Asturias 33003, Spain.
Brain Res Bull. 2023 Aug;200:110699. doi: 10.1016/j.brainresbull.2023.110699. Epub 2023 Jul 3.
The unpredictable chronic mild stress (UCMS) model has been used to induce depressive-like symptoms in animal models. Our work aims to evaluate the impact of environmental enrichment on male Wistar rats in an animal model for depression. For this purpose, we aim to assess changes in GR and GABAergic (PV+) density in cerebral regions related to cognitive-affective processes associated with depressive disorder, such as the dorsal- ventral hippocampus and accumbens nuclei. Three groups of rats were used: UCMs (unpredictable chronic mild stress), EE+ UCMs (enrichment + stress) and CONT (behavioral tests only). Hedonic responses elicited by sucrose solution were examined by licking behavior analysis; the anxiety level was evaluated using the elevated zero maze and the forced swimming (passive coping) tests. The environmental enrichment reduced the effects of chronic stress, promoting greater resilience. Thus, the UCMs group showed an anhedonia response, more anxiety and immobility behavior than either the control or the EE+ UCMs groups. Regarding immunochemistry results, there was a reduction in GABAergic activity coupled with increased activation of GR in UCMs in the dorsal hippocampus, but there were no differences between groups in the ventral hippocampus. These results suggest environmental enrichment could enhance greater resilience, reducing the vulnerability of the subjects to develop disorders such as depression and anxiety.
不可预测的慢性轻度应激（UCMS）模型已被用于诱导动物模型中的抑郁样症状。我们的工作旨在评估环境富集对雄性 Wistar 大鼠在抑郁动物模型中的影响。为此，我们旨在评估与抑郁障碍相关的认知情感过程相关的大脑区域中 GR 和 GABAergic（PV+）密度的变化，例如背侧-腹侧海马体和伏隔核。使用了三组大鼠：UCMs（不可预测的慢性轻度应激）、EE+ UCMs（富集+应激）和 CONT（仅行为测试）。通过舔舐行为分析检查蔗糖溶液引起的快感反应；使用高架零迷宫和强迫游泳（被动应对）测试评估焦虑水平。环境富集减轻了慢性应激的影响，促进了更大的适应力。因此，与 CONT 或 EE+ UCMs 组相比，UCMs 组表现出快感缺失反应、更多的焦虑和不动行为。关于免疫化学结果，在背侧海马体中，UCMs 中 GABA 能活性降低伴随着 GR 的激活增加，但腹侧海马体中各组之间没有差异。这些结果表明，环境富集可以增强更大的适应力，降低受试者易患抑郁和焦虑等障碍的脆弱性。
