恐惧条件反射机制研究的新进展

Progress in research of mechanisms of fear conditioning reflex

恐惧条件反射是条件性刺激和非条件性刺激联系在一起时，机体对条件性刺激产生的一种防御性反应。研究表明这两种刺激产生联系的关键部位是杏仁核外侧核区。当条件性刺激和非条件性刺激耦联时，Ca^2＋通过外侧核区突触上的N-甲基-D-天门冬氨酸受体和电压门控性Ca^2＋通道进入神经元，引起细胞内一系列分子反应，形成长时程增强，最终导致恐惧条件反射产生。

Fear conditioning reflex is a form of defense responses that subjects come to express to conditioned stimulus （CS） that are paired with unconditioned stimulus （US）. Considerable evidence suggests that critical site mediating CS-US association is located in lateral nucleus of amygdala （LA）. When CS-US association occurs, calcium influxes into neurons through NMDA receptors and through voltage-gated calcium channels on neural synapses of LA, and then initiates a cascade of intracellular reactions leading to synaptic transmission in a status of long-term potentiation. As a result, fear conditioning reflex forms.