Oxytocin modulation in the medial prefrontal cortex of pair-exposed rats during fear conditioning
Oxytocin modulation in the medial prefrontal cortex of pair-exposed rats during fear conditioning
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DOI：
10.1016/j.psyneuen.2022.105752
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发表时间：
2022-03-31
影响因子：
3.7
通讯作者：
Noh, Jihyun
中科院分区：
文献类型：
--
作者：
Jang, Minji;Jung, Taesub;Noh, Jihyun
简介：社会缓冲是一种现象，当动物处于同质关系中时，由于暴露于压力刺激而引起的压力和恐惧反应会减弱。由于社会存在，社会缓冲减少了啮齿动物的恐惧记忆行为，如逃避，回避和冻结行为。在这里，我们的目的是确定的恐惧行为和神经活动的变化在内侧前额叶皮层（mPFC）的存在下，另一只大鼠在恐惧暴露的条件下，并确认催产素在调节社会缓冲的mPFC的作用。方法：我们进行了被动回避实验，并确定阳性c-Fos表达在单和双暴露大鼠。茴香霉素（一种蛋白质合成抑制剂）和催产素受体调节剂（卡贝缩宫素;激动剂和阿托西班;拮抗剂）微量注射到mPFC中，以澄清催产素在mPFC中的作用。结果如下：虽然单暴露大鼠表现出显着增加，在冻结和被动回避行为相比，对照组大鼠，对暴露大鼠表现出显着较少的恐惧行为相比，单暴露大鼠。与对照组和单次暴露组相比，双暴露组大鼠前边缘mPFC区c-Fos表达显著增加。茴香霉素注射到对暴露大鼠的PL mPFC的对暴露的影响被阻断。此外，当卡贝缩宫素注射到单次暴露大鼠的PL mPFC中时，恐惧行为减少，并且这些变化被阿托西班阻断。讨论内容：我们的研究结果表明，减少恐惧相关的行为引起的急性对暴露是介导的催产素受体在PL mPFC。在恐惧诱导的情况下，与同种配对暴露有助于通过显着增加催产素在PL mPFC中的作用来应对恐惧。
Introduction: Social buffering is the phenomenon, in which stress and fear reactions caused by exposure to stressful stimuli when animals are exposed to homogeneous relationships are attenuated. Social buffering reduces fear memory behavior such as escape, avoidance, and freezing behavior in rodents due to social existence. Here, we aimed to determine alterations of fear behavior and neural activity in the medial prefrontal cortex (mPFC) in response to the presence of another rat in fear-exposed conditions and to confirm the role of oxytocin in mPFC in regulating social buffering. Methods: We performed a passive avoidance test and determined positive c-Fos expression in single- and pairexposed rats. Anisomycin (a protein synthesis inhibitor) and oxytocin receptor regulators (carbetocin; agonist and atosiban; antagonist) were microinjected into the mPFC to clarify the role of oxytocin in the mPFC. Results: While single-exposed rats showed a significant increase in both freezing and passive avoidance behaviors compared to control rats, pair-exposed rats showed significantly less fear behavior compared to single-exposed rats. The c-Fos expression in the prelimbic (PL) mPFC was significantly increased in pair-exposed rats compared to that in control and single-exposed rats. The pair-exposed effect was blocked by anisomycin injections into the PL mPFC of pair-exposed rats. Furthermore, when a carbetocin was injected into the PL mPFC in single-exposed rats, fear behavior was decreased, and these changes were blocked by atosiban. Discussion: Our findings suggest that reduction of fear-related behavior induced by acute pair-exposure is mediated by oxytocin receptors in the PL mPFC. Pair exposure with conspecifics during fear-inducing situations helps coping with fear by significantly increasing the role of oxytocin in the PL mPFC.