Maternal condition reduces fear behaviors but not the endocrine response to an emotional threat in virgin female rats
Maternal condition reduces fear behaviors but not the endocrine response to an emotional threat in virgin female rats
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DOI：
10.1016/j.yhbeh.2007.10.002
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发表时间：
2008-01-01
影响因子：
3.5
通讯作者：
Ferreira, A.
中科院分区：
文献类型：
--
作者：
Agrati, D.;Zuluaga, M. J.;Ferreira, A.
哺乳期的母鼠和母亲处女的女性是不那么可怕的行为测试相比，非产妇的动物，这表明产妇的条件本身减少了负面价值的威胁性刺激。此外，哺乳期女性对潜在环境威胁的下丘脑-垂体-肾上腺反应减弱。无论哺乳期的内分泌状况如何，母亲的病情能否促进对情绪压力源的行为反应和内分泌反应的减少？为了回答这个问题，在幼仔存在的情况下，在母体和非母体非卵巢切除的处女雌性和哺乳期母鼠中评价了焦虑相关和恐惧行为以及皮质酮水平，以响应明亮的开放场-大声噪声模型。母亲的动物，哺乳期和处女，提出了一个增加的探索明亮的开放领域和显着减少的恐惧行为，减少飞行和不动反应，随后激活的一个响亮的噪音，相比非产妇处女。有趣的是，母亲处女的女性，作为非产妇大鼠，表现出较高的皮质酮血浆水平，相反，较低的内分泌反应表现出的哺乳期母鼠时，面对这种威胁。目前的研究结果表明，母亲的条件允许女性承担风险时，照顾他们的年轻人，一种行为策略，是独立的减少下丘脑-垂体-肾上腺轴的反应特征的哺乳期。这一证据指向一个明确的分离的机制，调节行为和内分泌反应的情绪压力在母亲。(c)2007年爱思唯尔公司All rights reserved.
Lactating dams and maternal virgin females are less fearful in behavioral tests compared with non-maternal animals, suggesting that maternal condition per se reduces the negative value of threatening stimuli. In addition, lactating females exhibit a diminished hypothalamic-pituitary-adrenal response to potential environmental threats. Can the maternal condition, independently of the endocrine profile of lactation, promote a reduction in the behavioral as well as in the endocrine response to an emotional stressor? To answer this question, anxiety-related and fear behaviors as well as the levels of corticosterone were evaluated in response to a bright-lit open field-loud noise model in maternal and non-maternal non-ovariectomized virgin females and lactating dams in the presence of the pups. Maternal animals, both lactating and virgin, presented an increased exploration of the bright-lit open field and a significant reduction of fear behaviors, indicated by the decreased flight and immobility responses to the subsequent activation of a loud noise, in comparison to non-maternal virgins. Interestingly, maternal virgin females, as non-maternal rats, showed high corticosterone plasma levels, in contrast to the lower endocrine response exhibited by lactating dams when confronted to this threat. Present results suggest that maternal condition allows females to take risks when caring for their young, a behavioral strategy that is independent of the reduced hypothalamic-pituitary-adrenal axis response characteristic of lactation. This evidence points towards a clear dissociation in the mechanisms regulating behavioral and endocrine responses to emotional stressors during motherhood. (c) 2007 Elsevier Inc. All rights reserved.