Role of early environmental enrichment on the social dominance tube test at adulthood in the rat
Role of early environmental enrichment on the social dominance tube test at adulthood in the rat
复制标题
早期环境丰富对大鼠成年期社会支配管试验的作用
DOI：
10.1007/s00213-017-4717-3
复制
发表时间：
2017-11-01
影响因子：
3.4
通讯作者：
Li, Chang-Qi
中科院分区：
文献类型：
--
作者：
Cao, Wen-Yu;Hu, Zhao-Lan;Li, Chang-Qi
基本原理环境富集（EE）可以影响啮齿类动物的大脑可塑性和行为。早期EE是否可能使个体在成年后的社会支配管测试（SDTT）中倾向于特定的社会等级尚不清楚。目的本研究直接调查EE对成年大鼠SDTT竞争成功的影响。方法雄性大鼠在出生后21至35天维持EE。通过SDTT、竞争性食物觅食试验和成年期的配偶偏好测试来确定社会支配行为。采用免疫组织化学和蛋白质印迹法检测下丘脑中IBA-1的表达。结果在SDTT中，EE大鼠在与标准环境(SE)大鼠的社交接触中容易变得顺从。在SE和EE大鼠的竞争性觅食试验中，未发现觅食方面存在差异。在择偶测试中，雄性 EE 大鼠比 SE 大鼠对雌性大鼠更具吸引力。与 SE 组相比，EE 组大鼠下丘脑中 IBA-1 表达降低。输注小胶质细胞抑制剂降低了 SE 大鼠在 SDTT 中的前向百分比。 DNA甲基转移酶抑制剂的输注阻止了EE大鼠从属状态的发展，并恢复了下丘脑IBA-1的表达。结论结果表明，早期EE并没有导致雄性大鼠社会等级的降低。然而，EE 导致 SDTT 中前向百分比减少，这可能与下丘脑小胶质细胞数量减少有关。
RationaleEnvironmental enrichment (EE) could influence brain plasticity and behavior in rodents. Whether the early EE may predispose individuals to a particular social hierarchy in the social dominance tube test (SDTT) at adulthood is still unknown.ObjectiveThe present study directly investigated the influence of EE on competitive success in the SDTT among adult rats.MethodsMale rats were maintained in EE from postnatal days 21 to 35. Social dominance behavior was determined by SDTT, competitive food foraging test, and mate preference test at adulthood. IBA-1 expression in the hypothalamus was examined using immunohistochemistry and western blot.ResultsEE rats were prone to become submissive during a social encounter with standard environment (SE) rats in the SDTT. No difference was found in food foraging in the competitive food foraging test between SE and EE rats. Male EE rats were more attractive than the SE to the female rats in the mate preference test. IBA-1 expression was found to be decreased in the hypothalamus of EE rats compared to SE group. Infusion of a microglia inhibitor reduced percentage of forward in SE rats in the SDTT. Infusion of DNA methyltransferase inhibitor prevented the development of subordinate status in EE rats and restored the expression of IBA-1 in the hypothalamus.ConclusionsThe results suggest that early EE did not lead to reduced social hierarchy in the male rat. However, EE caused a reduction in the percentage of forward in the SDTT, which might be associated with reduced number of microglia in the hypothalamus.