Life Sciences Research, The University at Albany-SUNY Albany, NY, USA.
Front Cell Neurosci. 2012 Dec 18;6:40. doi: 10.3389/fncel.2012.00040. eCollection 2012.
Stressors, during early life or adulthood, can alter steroid-sensitive behaviors, such as exploration, anxiety, and/or cognitive processes. We investigated if exposure to acute stressors in adulthood may alter behavioral and neuroendocrine responses of male rats that were exposed to gestational stress or not. We hypothesized that rats exposed to gestational and acute stress may show behavioral inhibition, increased corticosterone, and altered androgen levels in the hippocampus. Subjects were adult, male offspring of rat dams that were restrained daily on gestational days 14-20, or did not experience this manipulation. Immediately before testing, rats were restraint stressed for 20 min or not. During week 1, rats were tested in a battery of tasks, including the open field, elevated plus maze, social interaction, tailflick, pawlick, and defensive burying tasks. During week 2, rats were trained and tested 24 h later in the inhibitory avoidance task. Plasma corticosterone and androgen levels, and hippocampal androgen levels, were measured in all subjects. Gestational and acute restraint stress increased plasma levels of corticosterone, and reduced levels of testosterone's 5α-reduced metabolites, dihydrotestosterone (DHT) and 3α-androstanediol (3α-diol), but not the aromatized metabolite, estradiol (E(2)), in plasma or the hippocampus. Gestational and acute restraint stress reduced central entries made in the open field, and latencies to enter the shock-associated side of the inhibitory avoidance chamber during testing. Gestational stress reduced time spent interacting with a conspecific. These data suggest that gestational and acute restraint stress can have actions to produce behavioral inhibition coincident with increased corticosterone and decreased 5α-reduced androgens of adult male rats. Thus, gestational stress altered neural circuits involved in the neuroendocrine response to acute stress in early adulthood.
应激源,无论是在生命早期还是成年期,都可能改变类固醇敏感行为,如探索、焦虑和/或认知过程。我们研究了成年期暴露于急性应激源是否会改变曾经历过妊娠期应激或未经历过妊娠期应激的雄性大鼠的行为和神经内分泌反应。我们假设,暴露于妊娠期和急性应激的大鼠可能表现出行为抑制、皮质酮增加和海马中雄激素水平改变。实验对象为成年雄性大鼠,其母鼠在妊娠第 14-20 天期间每天被束缚,或未经历这种操作。在测试前,大鼠立即被束缚应激 20 分钟或不被束缚。在第 1 周,大鼠接受一系列任务的测试,包括开阔场、高架十字迷宫、社交互动、甩尾、爪舔和防御性掩埋任务。在第 2 周,大鼠接受训练,并在 24 小时后进行抑制性回避任务的测试。所有大鼠均测量血浆皮质酮和雄激素水平以及海马雄激素水平。妊娠期和急性束缚应激增加了血浆皮质酮水平,并降低了血浆和海马中睾酮的 5α-还原代谢物二氢睾酮(DHT)和 3α-雄烷二醇(3α-diol)的水平,但未降低芳香化代谢物雌二醇(E(2))的水平。妊娠期和急性束缚应激减少了大鼠在开阔场中的中央进入次数,以及在测试中进入抑制性回避室与电击相关侧的潜伏期。妊娠期应激减少了与同物种互动的时间。这些数据表明,妊娠期和急性束缚应激会导致行为抑制,同时增加成年雄性大鼠的皮质酮和减少 5α-还原雄激素。因此,妊娠期应激改变了参与成年早期急性应激神经内分泌反应的神经回路。