小鼠与生俱来的探测危险、保护后代和探测社会边界的能力取决于一种在大脑的恐惧神经回路中浓度高的分子。Gleb Shumyatsky及其同事扩展了他们此前的报告，它表明了大脑的生物化学变化可以消除小鼠的恐惧。两项研究都把重点放在杏仁核上，它是大脑的一部分，与恐惧有关，而且与产后焦虑和自闭症等疾病有联系。杏仁核的一个区域——基底外侧核（BLA）——在产生学习到的恐惧方面担任的角色已经确定，但是这组科学家分析了BLA是否控制着其他对个体和物种生存至关重要的行为。它们研究了失去stathmin基因——它在BLA相关的神经回路中的浓度较高——的小鼠的母亲和社会行为。
这组科学家证明了失去这个基因的雌性小鼠比对照组小鼠在行为测试上表现出的焦虑更少，而且没能探测到危险，其证据是它们在暴露的地区修筑了它们的巢，而且没能找回从巢中移走的幼崽。当这组科学家破坏了正常小鼠的BLA的一部分之后，同样的缺乏母亲危险探测和关照的情况出现在这些小鼠身上。这组科学家说，这种敲除小鼠和它们的同伴的互动也比未改变的小鼠更多，这种响应具有社会等级方面的意义。相关论文发表在美国《国家科学院院刊》（PNAS）上。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS，doi: 10.1073/pnas.0807507105，Guillaume Martel，Gleb P. Shumyatsky
Stathmin reveals dissociable roles of the basolateral amygdala in parental and social behaviors
Guillaume Martel, Akinori Nishi, and Gleb P. Shumyatsky
Innate parental behaviors and adult social interactions are essential for survival of the individual along with the species as a whole. Because these behaviors require threat assessment of the environment, it is plausible that they are regulated by the amygdala-associated neural circuitry of fear. However, the amygdala is not a single anatomic and functional unit, and nuclei of the amygdala have multiple inter- and intra-connections. This poses a question as to the exact role of different amygdala nuclei in these behaviors and the mechanisms involved. The basolateral complex of the amygdala nuclei (BLA) is particularly interesting in this regard: although the BLA role in forming memories for learned fear is established, the BLA role in innate behaviors is not well understood. We recently demonstrated that mice without an inhibitor of microtubules, stathmin, a gene enriched in BLA-associated circuitry, have deficiency in innate and learned fear. Here we show that the deficiency in fear processing in stathmin−/− females leads to improper threat assessment, which in turn affects innate parental care and adult social interactions. Profound deficiency is observed in maternal behavior of stathmin−/−females: they lack motivation for retrieving pups and are unable to choose a safe location for nest-building. Remarkably, stathmin−/− females have an enhancement in social interactions. BLA lesions in WT mice produce similar effects in maternal and social behaviors, confirming vital BLA participation. The findings implicate stathmin as the critical molecular component linking the BLA-associated neural circuitry with innate parental behaviors and adult social interactions.
