Darnaudéry Muriel, Dutriez Isabelle, Viltart Odile, Morley-Fletcher Sara, Maccari Stefania
Laboratoire du Stress Périnatal, JE 2365, Université de Lille 1, Villeneuve d'Ascq 59655, France.
Behav Brain Res. 2004 Aug 12;153(1):211-6. doi: 10.1016/j.bbr.2003.12.001.
Human and animal studies indicate that repeated stress during pregnancy can produce long-term biological and behavioural disorders in the offspring. In contrast, although maternal stress is supposed to induce an increase of maternal anxiety, few studies have been conducted to demonstrate it. Therefore, in the present study we examined the emotional reactivity in stressed (chronic restraint stress applied 3 x 45 min per day during the last week of pregnancy) and unstressed females rats after the weaning of their pups. Restraint stress procedure reduced the body weight gain both during pregnancy and up to four weeks after the stress period. Stressed dams presented a reduction of exploration and of corticosterone levels when exposed to a novel environment (25 and 49 days post-stress). They spent less time in the open arms of the elevated plus-maze (26 days post-stress). Finally, they showed no increase in the time spent in immobility after a second exposure to the forced-swim test (35-36 days post-stress). In the contrary, such differences were not observed when the chronic stress procedure was applied on virgin females. Overall, our results show that, chronic stress during gestation induces lasting effects on emotional reactivity of the dams, thus indicating that gestation constitutes a critical period in the vulnerability to stressful events also for the mother.
人类和动物研究表明，孕期反复应激可使后代出现长期的生物学和行为紊乱。相比之下，尽管母体应激理应会导致母体焦虑增加，但很少有研究对此进行验证。因此，在本研究中，我们在雌性大鼠幼崽断奶后，检测了应激（在孕期最后一周每天施加3次，每次45分钟的慢性束缚应激）和未应激雌性大鼠的情绪反应性。束缚应激程序在孕期以及应激期结束后的四周内均降低了体重增加。应激母鼠在暴露于新环境时（应激后25天和49天），探索行为和皮质酮水平均降低。它们在高架十字迷宫开放臂中停留的时间减少（应激后26天）。最后，在再次进行强迫游泳试验时（应激后35 - 36天），它们静止不动的时间没有增加。相反，对未孕雌性大鼠施加慢性应激程序时，未观察到此类差异。总体而言，我们的结果表明，孕期慢性应激会对母鼠的情绪反应性产生持久影响，这表明孕期对母亲而言也是易受应激事件影响的关键时期。
