Grillon Christian, Levenson Jessica, Pine Daniel S
Mood and Anxiety Disorders Program, National Institute of Mental Health, NIH, Bethesda, MD 20892-2670, USA.
Neuropsychopharmacology. 2007 Jan;32(1):225-31. doi: 10.1038/sj.npp.1301204. Epub 2006 Sep 13.
Serotonin reuptake inhibitors may increase symptoms of anxiety immediately following treatment initiation. The present study examined whether acute citalopram increased fear-potentiated startle to predictable and/or unpredictable shocks in healthy subjects. Eighteen healthy subjects each received two treatments, placebo and 20 mg citalopram in a crossover design. Participants were exposed to three conditions including one in which predictable aversive shocks were signaled by a cue, a second in which unpredictable shocks were anticipated, and a third in which no shocks were administered. Changes in aversive states were investigated using acoustic startle stimuli. Citalopram did not affect baseline startle. However, the phasic startle potentiation to the threat cue in the predictable condition was robustly increased by acute citalopram. The sustained startle potentiation in the unpredictable conditions was also increased by citalopram, but only when the drug was given during the first session. These results indicate that a single dose of citalopram is not anxiogenic in itself, but can exacerbate the expression of fear and anxiety.
血清素再摄取抑制剂在开始治疗后可能会立即加重焦虑症状。本研究检验了急性服用西酞普兰是否会增加健康受试者对可预测和/或不可预测电击的恐惧增强惊吓反应。18名健康受试者采用交叉设计，每人接受两种治疗，即安慰剂和20毫克西酞普兰。参与者暴露于三种情境中，一种是通过提示信号表示可预测的厌恶电击，第二种是预期不可预测的电击，第三种是不施加电击。使用听觉惊吓刺激来研究厌恶状态的变化。西酞普兰不影响基线惊吓反应。然而，急性服用西酞普兰会显著增强可预测情境中对威胁提示的阶段性惊吓增强反应。西酞普兰也会增加不可预测情境中持续的惊吓增强反应，但仅当在第一阶段给药时才会出现这种情况。这些结果表明，单剂量西酞普兰本身不会引起焦虑，但会加剧恐惧和焦虑的表现。
