Bindi Ricardo Passoni, Baldo Marcus Vinicius C, Canteras Newton Sabino
Dept. Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP 05508-000, Brazil.
Dept. Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP 05508-000, Brazil.
Behav Brain Res. 2018 Apr 16;342:51-56. doi: 10.1016/j.bbr.2018.01.016. Epub 2018 Feb 4.
The basolateral amygdala complex, which includes the lateral, basolateral and basomedial nuclei, has been implicated in innate and contextual fear responses to predator threats. In the basolateral complex, the lateral and posterior basomedial nuclei are able to process predator odor information, and they project to the predator-responsive hypothalamic circuit; lesions in these amygdalar sites reduce innate responses and practically abolish contextual fear responses to predatory threats. In contrast to the lateral and posterior basomedial nuclei, the basolateral nucleus does not receive direct information from predator olfactory cues and has no direct link to the predator-responsive hypothalamic circuit. No attempt has previously been made to determine the specific role of the basolateral nucleus in fear responses to predatory threats, and we currently addressed this question by making bilateral N-methyl-D-aspartate lesions in the anterior basolateral nucleus of the amygdala (BLAa), which is often regarded as being contiguous with the lateral amygdalar nucleus, and tested both innate and contextual fear in response to cat exposure. Accordingly, BLAa lesions decreased both innate and contextual fear responses to predator exposure. Considering the targets of the BLAa, the nucleus accumbens appears to be a potential candidate to influence innate defensive responses to predator threats. The present findings also suggest that the BLAa has a role in fear memory of predator threat. The BLAa is likely involved in memory consolidation, which could potentially engage BLAa projection targets, opening interesting possibilities in the investigation of how these targets could be involved in the consolidation of predator-related fear memory.
基底外侧杏仁核复合体，包括外侧核、基底外侧核和基底内侧核，已被证明与对捕食者威胁的先天及情境性恐惧反应有关。在基底外侧复合体中，外侧核和基底内侧后核能够处理捕食者气味信息，并投射到对捕食者有反应的下丘脑回路；这些杏仁核部位的损伤会降低先天反应，并几乎消除对捕食者威胁的情境性恐惧反应。与外侧核和基底内侧后核不同，基底外侧核不直接接收来自捕食者嗅觉线索的信息，也与对捕食者有反应的下丘脑回路没有直接联系。此前尚未有人尝试确定基底外侧核在对捕食者威胁的恐惧反应中的具体作用，我们目前通过在杏仁核前基底外侧核（BLAa）制作双侧N-甲基-D-天冬氨酸损伤来解决这个问题，该部位通常被认为与外侧杏仁核相邻，并测试了对猫暴露的先天和情境性恐惧反应。因此，BLAa损伤降低了对捕食者暴露的先天和情境性恐惧反应。考虑到BLAa的靶点，伏隔核似乎是影响对捕食者威胁的先天防御反应的潜在候选者。目前的研究结果还表明，BLAa在对捕食者威胁的恐惧记忆中起作用。BLAa可能参与记忆巩固，这可能会涉及BLAa的投射靶点，为研究这些靶点如何参与与捕食者相关的恐惧记忆巩固开辟了有趣的可能性。
