Strobel Cornelia, Marek Roger, Gooch Helen M, Sullivan Robert K P, Sah Pankaj
The Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
The Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
Cell Rep. 2015 Mar 10;10(9):1435-1442. doi: 10.1016/j.celrep.2015.02.008. Epub 2015 Mar 5.
The basolateral amygdala (BLA) and prefrontal cortex (PFC) are partners in fear learning and extinction. Intercalated (ITC) cells are inhibitory neurons that surround the BLA. Lateral ITC (lITC) neurons provide feed-forward inhibition to BLA principal neurons, whereas medial ITC (mITC) neurons form an inhibitory interface between the BLA and central amygdala (CeA). Notably, infralimbic prefrontal (IL) input to mITC neurons is thought to play a key role in fear extinction. Here, using targeted optogenetic stimulation, we show that lITC neurons receive auditory input from cortical and thalamic regions. IL inputs innervate principal neurons in the BLA but not mITC neurons. These results suggest that (1) these neurons may play a more central role in fear learning as both lITCs and mITCs receive auditory input and that (2) mITC neurons cannot be driven directly by the IL, and their role in fear extinction is likely mediated via the BLA.
基底外侧杏仁核（BLA）和前额叶皮层（PFC）是恐惧学习和消退过程中的协同部分。闰细胞（ITC）是环绕BLA的抑制性神经元。外侧ITC（lITC）神经元对BLA主神经元提供前馈抑制，而内侧ITC（mITC）神经元在BLA和中央杏仁核（CeA）之间形成一个抑制性界面。值得注意的是，前额叶下缘（IL）向mITC神经元的输入被认为在恐惧消退中起关键作用。在这里，通过靶向光遗传学刺激，我们发现lITC神经元接收来自皮层和丘脑区域的听觉输入。IL输入支配BLA中的主神经元，但不支配mITC神经元。这些结果表明：（1）由于lITC和mITC都接收听觉输入，这些神经元可能在恐惧学习中发挥更核心的作用；（2）mITC神经元不能被IL直接驱动，它们在恐惧消退中的作用可能是通过BLA介导的。
