Borowski T B, Kokkinidis L
Department of Psychology, University of Saskatchewan, Saskatoon, Canada.
Behav Neurosci. 1996 Dec;110(6):1349-64. doi: 10.1037//0735-7044.110.6.1349.
Potentiated startle was used in this study to determine the fear-motivational functions of the ventral tegmental area (VTA). In Experiment 1, electrical stimulation of the VTA increased acoustic startle amplitudes. In subsequent experiments fear-potentiated startle was assessed following axon-sparing N-methyl-D-aspartic acid (NMDA) lesions of the VTA and after bilateral intra-VTA infusion of the dopamine (DA) D2/3 receptor agonist quinpirole. The NMDA lesions produced substantial cell loss in the medial ventral tegmentum and suppressed fear expression. Similarly, inhibition of DA neuronal activity associated with locally administered quinpirole blocked fear-potentiated startle. It was suggested that VTA neurons and their forebrain DA projections regulate levels of aversive emotional arousal within the amygdala-based fear system.
在本研究中，采用增强惊吓反应来确定腹侧被盖区（VTA）的恐惧动机功能。在实验1中，对VTA进行电刺激会增加听觉惊吓反应的幅度。在随后的实验中，在对VTA进行保留轴突的N-甲基-D-天冬氨酸（NMDA）损伤后，以及在双侧VTA内注射多巴胺（DA）D2/3受体激动剂喹吡罗后，评估恐惧增强惊吓反应。NMDA损伤导致内侧腹侧被盖区大量细胞丢失，并抑制恐惧表达。同样，与局部给予喹吡罗相关的DA神经元活动抑制也阻断了恐惧增强惊吓反应。研究表明，VTA神经元及其前脑DA投射调节基于杏仁核的恐惧系统内的厌恶情绪唤醒水平。
