Tejeda Hugo A, O'Donnell Patricio
Department of Anatomy and Neurobiology, Program in Neuroscience/National Institutes of Health Graduate Partnership Program, and
Department of Anatomy and Neurobiology, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, Maryland 21201
J Neurosci. 2014 Oct 22;34(43):14365-74. doi: 10.1523/JNEUROSCI.0837-14.2014.
Whereas cooperative communication between the hippocampus (HP) and prefrontal cortex (PFC) is critical for cognitive functions, an antagonistic relationship may exist between the basolateral amygdala (BLA) and PFC during emotional processing. As PFC neurons integrate information from converging excitatory BLA and HP inputs, we explored whether the ability of BLA inputs to evoke feedforward inhibition in the PFC affects converging HP synaptic inputs using in vivo intracellular recordings in anesthetized rats. BLA train stimulation decreased HP synaptic responses in the PFC in vivo. This effect was dependent on the timing of HP-evoked responses and the strength of BLA activation. BLA train stimulation also produced heterosynaptic suppression of responses from the amygdalo-piriform cortex, an associative temporal cortical structure. Heterosynaptic suppression was unidirectional as HP trains failed to modify BLA synaptic responses. These findings provide a mechanism by which BLA activation could decrease PFC neural activity and transiently attenuate the HP influence on PFC function.
虽然海马体（HP）与前额叶皮质（PFC）之间的协同通信对认知功能至关重要，但在情绪处理过程中，基底外侧杏仁核（BLA）与PFC之间可能存在拮抗关系。由于PFC神经元整合来自汇聚的兴奋性BLA和HP输入的信息，我们利用麻醉大鼠的体内细胞内记录，探究了BLA输入在PFC中诱发前馈抑制的能力是否会影响汇聚的HP突触输入。BLA串刺激在体内降低了PFC中的HP突触反应。这种效应取决于HP诱发反应的时间和BLA激活的强度。BLA串刺激还对杏仁核-梨状皮质（一种联合颞叶皮质结构）的反应产生了异突触抑制。异突触抑制是单向的，因为HP串未能改变BLA突触反应。这些发现提供了一种机制，通过该机制BLA激活可降低PFC神经活动，并暂时减弱HP对PFC功能的影响。
