The perifornical area of the hypothalamus has been known as the center for the defense response, or fight-or-flight response, which is characterized by a concomitant rise in arterial blood pressure, heart rate, and respiratory frequency. It is well established that orexin neurons, which are located in this region, play a critical role in this response. In this study, we further examined this role by recording orexin neuronal activity and heart rate in freely moving mice using an original dual-channel fiber photometry system in vivo. Analysis of orexin neuron activity in relation to autonomic responses to aversive stimuli revealed a rapid increase in neuronal activity just prior to changes in heart rate. In addition, we examined whether orexin neurons would be activated by a conditioned neutral sound that was previously associated with aversive stimulus. We show that the memory of the aversive stimulus activated orexin neurons and increased heart rate. Our data suggest that orexin neurons are a key component linking aversive emotions to autonomic defense response. Our data also suggest that targeting orexin neurons may enable treatment of psychiatric disorders associated with chronic stress and traumatic memories.

中文翻译：

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厌恶情绪迅速激活食欲素神经元并增加自由运动小鼠的心率

下丘脑的前缘区域被称为防御反应或战斗或逃跑反应的中心，其特征是动脉血压、心率和呼吸频率随之升高。众所周知，位于该区域的食欲素神经元在该反应中起关键作用。在这项研究中，我们通过在体内使用原始双通道光纤光度计系统记录自由移动小鼠的食欲素神经元活动和心率，进一步检验了这一作用。对与厌恶刺激的自主反应相关的食欲素神经元活动的分析揭示了在心率变化之前神经元活动的快速增加。此外，我们检查了食欲素神经元是否会被以前与厌恶刺激相关的条件性中性声音激活。我们表明，厌恶刺激的记忆激活了食欲素神经元并增加了心率。我们的数据表明，食欲素神经元是将厌恶情绪与自主防御反应联系起来的关键成分。我们的数据还表明，靶向食欲素神经元可能有助于治疗与慢性压力和创伤性记忆相关的精神疾病。