Department of Psychology, Behavioral Neuroscience Program, University of Delaware, Newark, DE 19716, USA.
Neuropsychopharmacology. 2010 Dec;35(13):2607-16. doi: 10.1038/npp.2010.155. Epub 2010 Sep 15.
Oxytocin reportedly decreases anxious feelings in humans and may therefore have therapeutic value for anxiety disorders, such as post-traumatic stress disorder (PTSD). As PTSD patients have exaggerated startle responses, a fear-potentiated startle paradigm in rats may have face validity as an animal model to examine the efficacy of oxytocin in treating these symptoms. Oxytocin (0, 0.01, 0.1, or 1.0 μg, subcutaneously) was given either 30 min before fear conditioning, immediately after fear conditioning, or 30 min before fear-potentiated startle testing to assess its effects on acquisition, consolidation, and expression of conditioned fear, respectively. Startle both in the presence and absence of the fear-conditioned light was significantly diminished by oxytocin when administered at acquisition, consolidation, or expression. There was no specific effect of oxytocin on light fear-potentiated startle. In an additional experiment, oxytocin had no effects on acoustic startle without previous fear conditioning. Further, in a context-conditioned test, previous light-shock fear conditioning did not increase acoustic startle during testing when the fear-conditioned light was not presented. The data suggest that oxytocin did not diminish cue-specific conditioned nor contextually conditioned fear, but reduced background anxiety. This suggests that oxytocin has unique effects of decreasing background anxiety without affecting learning and memory of a specific traumatic event. Oxytocin may have antianxiety properties that are particularly germane to the hyper-vigilance and exaggerated startle typically seen in PTSD patients.
据报道，催产素可减少人类的焦虑感，因此对焦虑症（如创伤后应激障碍，PTSD）可能具有治疗价值。由于 PTSD 患者的惊吓反应过度，因此大鼠的恐惧增强性惊吓范式可能具有作为检查催产素治疗这些症状疗效的动物模型的表面有效性。催产素（0、0.01、0.1 或 1.0μg，皮下注射）分别在恐惧条件作用之前 30 分钟、恐惧条件作用后立即或恐惧增强性惊吓测试之前 30 分钟给予，以分别评估其对条件恐惧获得、巩固和表达的影响。在存在和不存在恐惧条件光的情况下，催产素给药时均明显减少了惊吓。催产素对光恐惧增强性惊吓没有特定作用。在另外一项实验中，在没有先前恐惧条件作用的情况下，催产素对听觉惊吓没有影响。此外，在情境条件作用测试中，当不呈现恐惧条件光时，先前的光-休克恐惧条件作用不会增加测试期间的听觉惊吓。数据表明，催产素不会减少线索特异性条件恐惧或情境条件恐惧，但会降低背景焦虑。这表明催产素具有降低背景焦虑的独特作用，而不会影响对特定创伤事件的学习和记忆。催产素可能具有抗焦虑特性，这与 PTSD 患者通常所见的过度警惕和惊吓反应过度特别相关。
