Background

Electroconvulsive therapy (ECT) is an effective treatment for depressive disorders, although its molecular mechanism of action is unknown. The serotonin 1B (5-HT_1B) receptor is a potential target for treatment of depression and low 5-HT_1B receptor binding in limbic regions has been reported in previous positron emission tomography (PET) studies of depression.

Methods

The objective of this longitudinal PET study was to examine the effect of ECT for depression on 5-HT_1B receptor binding. Fifteen hospitalized patients with major depressive episodes were examined with PET and the 5-HT_1B receptor selective radioligand [¹¹C]AZ10419369, before and after ECT. Fifteen controls matched for age and sex were examined. Limbic regions with previously reported low 5-HT_1B receptor binding in depression and a dorsal brain stem region were selected.

Results

Thirteen patients completed the study according to protocol. Eleven out of thirteen patients responded to ECT. 5-HT_1B receptor binding in hippocampus increased with 30 % after ECT (p=0.021). Using linear mixed effects modelling, we observed increases in 5-HT_1B receptor binding following ECT with a moderate to large effect size, which did not differ significantly between regions. In an exploratory analysis, strong correlations between changes in 5-HT_1B receptor binding and agitation scores on the Hamilton Depression Rating Scale after ECT were observed.

Limitations

Albeit representative of a PET study, the sample size is still small and there are potential confounding effects of medication.

Conclusions

Increased 5-HT_1B receptor binding was observed following ECT for depression, corresponding to previous findings of increased 5-HT_1B receptor binding in hippocampus after rapid acting ketamine for treatment resistant depression.

中文翻译：

---

正电子发射断层扫描电休克疗法对重度抑郁症发作的血清素1B受体效应的研究

背景

电休克疗法 (ECT) 是治疗抑郁症的有效方法，但其分子作用机制尚不清楚。5-羟色胺 1B (5-HT _1B ) 受体是治疗抑郁症的潜在靶标，之前的正电子发射断层扫描 (PET) 抑郁症研究报告了边缘区5-HT _1B受体结合率低。

方法

这项纵向PET研究的目的是检查ECT治疗抑郁症对5-HT _1B受体结合的影响。15 名患有重度抑郁发作的住院患者在 ECT 前后接受了 PET 和 5-HT _1B受体选择性放射性配体 [ ¹¹ C] AZ10419369 的检查。检查了年龄和性别匹配的 15 个对照。选择了先前报道的在抑郁症中具有低 5-HT _1B受体结合的边缘区域和背侧脑干区域。

结果

13 名患者根据方案完成了研究。13 名患者中有 11 名对 ECT 有反应。ECT 后海马中的5-HT _1B受体结合增加了 30% ( p = 0.021)。使用线性混合效应模型，我们观察到ECT后 5-HT _1B受体结合增加，效应大小为中到大，区域之间没有显着差异。在一项探索性分析中，观察到 ECT 后5-HT _1B受体结合的变化与汉密尔顿抑郁量表的激越评分之间存在强相关性。

限制

尽管 PET 研究具有代表性，但样本量仍然很小，并且存在药物的潜在混杂效应。

结论

提高了5-HT _1B受体的结合，观察到以下ECT抑郁症中，对应于增加的5-HT的先前的发现_1B速效氯胺酮治疗难治性抑郁症后海马结合受体。