Rzepa Ewelina, Dean Zola, McCabe Ciara
School of Psychology and Clinical Language Sciences, University of Reading, UK.
Int J Neuropsychopharmacol. 2017 Jun 1;20(6):455-462. doi: 10.1093/ijnp/pyx016.
Patients on the selective serotonergic reuptake inhibitors like citalopram report emotional blunting. We showed previously that citalopram reduces resting-state functional connectivity in healthy volunteers in a number of brain regions, including the dorso-medial prefrontal cortex, which may be related to its clinical effects. Bupropion is a dopaminergic and noradrenergic reuptake inhibitor and is not reported to cause emotional blunting. However, how bupropion affects resting-state functional connectivity in healthy controls remains unknown.
Using a within-subjects, repeated-measures, double-blind, crossover design, we examined 17 healthy volunteers (9 female, 8 male). Volunteers received 7 days of bupropion (150 mg/d) and 7 days of placebo treatment and underwent resting-state functional Magnetic Resonance Imaging. We selected seed regions in the salience network (amygdala and pregenual anterior cingulate cortex) and the central executive network (dorsal medial prefrontal cortex). Mood and anhedonia measures were also recorded and examined in relation to resting-state functional connectivity.
Relative to placebo, bupropion increased resting-state functional connectivity in healthy volunteers between the dorsal medial prefrontal cortex seed region and the posterior cingulate cortex and the precuneus cortex, key parts of the default mode network.
These results are opposite to that which we found with 7 days treatment of citalopram in healthy volunteers. These results reflect a different mechanism of action of bupropion compared with selective serotonergic reuptake inhibitors. These results help explain the apparent lack of emotional blunting caused by bupropion in depressed patients.
服用西酞普兰等选择性5-羟色胺再摄取抑制剂的患者会出现情感迟钝。我们之前表明，西酞普兰会降低包括背内侧前额叶皮质在内的多个脑区健康志愿者的静息态功能连接，这可能与其临床效果有关。安非他酮是一种多巴胺能和去甲肾上腺素能再摄取抑制剂，尚无报告称其会导致情感迟钝。然而，安非他酮如何影响健康对照者的静息态功能连接仍不清楚。
采用受试者内重复测量双盲交叉设计，我们对17名健康志愿者（9名女性，8名男性）进行了研究。志愿者接受了7天的安非他酮（150毫克/天）和7天的安慰剂治疗，并接受了静息态功能磁共振成像检查。我们在突显网络（杏仁核和膝前扣带回皮质）和中央执行网络（背内侧前额叶皮质）中选择了种子区域。还记录并检查了情绪和快感缺失测量指标与静息态功能连接的关系。
与安慰剂相比，安非他酮增加了健康志愿者背内侧前额叶皮质种子区域与后扣带回皮质和楔前叶皮质（默认模式网络的关键部分）之间的静息态功能连接。
这些结果与我们在健康志愿者中使用7天西酞普兰治疗时发现的结果相反。这些结果反映了安非他酮与选择性5-羟色胺再摄取抑制剂不同的作用机制。这些结果有助于解释安非他酮在抑郁症患者中明显不会导致情感迟钝的原因。
