Department of Clinical Psychology, Humboldt University, Berlin, Germany.
World J Biol Psychiatry. 2010 Sep;11(6):781-7. doi: 10.3109/15622975.2010.491127.
Depression, a disease usually accompanied by a serotonergic deficit, has been observed in about 40% of patients suffering from Parkinson's disease (PD). Thus, a serotonergic dysfunction in PD can be assumed. We aimed to investigate the interaction between serotonergic (5-HT) and dopaminergic activity in early PD. We hypothesized a serotonergic as well as a dopaminergic deficit in PD patients. We also assumed a correlation between these neurotransmitters indicating a relationship between dopaminergic and serotonergic function in PD.
Nine unmedicated PD patients before and 12 weeks after L-dopa treatment and nine healthy subjects were examined using the loudness dependence of auditory evoked potentials (LDAEP), a promising indicator of central serotonergic function. Dopaminergic transporters (DAT) were collected using (123)I-FP-CIT and single photon emission computer tomography (SPECT). LDAEP values were correlated with (123)I-FP-CIT SPECT data.
A significant difference between LDAEP of controls and patients (P= 0.05) suggested lower serotonergic activity in PD. Twelve weeks after initiation of L-dopa treatment this difference was lost between patients and controls (P= 0.20). There was a trend towards a correlation between LDAEP and DAT (r= 0.65; P = 0.057) of the unmedicated patients, suggesting a low serotonergic activity may be related to a dopamine deficit in PD.
Our results support the hypothesis that serotonergic neurotransmission is decreased in untreated PD and suggest that a low serotonergic activity may be related to the dopamine pathology in PD. This could be related to the high prevalence of depression in PD.
抑郁症通常伴随着 5-羟色胺（5-HT）缺乏，约 40%的帕金森病（PD）患者患有抑郁症。因此，可假设 PD 中存在 5-HT 能功能障碍。我们旨在研究早期 PD 中 5-HT 能和多巴胺能活性的相互作用。我们假设 PD 患者存在 5-HT 能和多巴胺能缺陷。我们还假设这些神经递质之间存在相关性，表明 PD 中多巴胺能和 5-HT 能功能之间存在关系。
使用响度依赖听觉诱发电位（LDAEP）检查 9 名未经治疗的 PD 患者在开始左旋多巴治疗前和治疗 12 周后的情况，LDAEP 是中枢 5-HT 能功能的一个很有前途的指标。使用（123）I-FP-CIT 和单光子发射计算机断层扫描（SPECT）收集多巴胺转运蛋白（DAT）。将 LDAEP 值与（123）I-FP-CIT SPECT 数据相关联。
对照组和患者的 LDAEP 存在显著差异（P=0.05），表明 PD 患者的 5-HT 能活性较低。在开始左旋多巴治疗 12 周后，患者和对照组之间的差异消失（P=0.20）。未经治疗的患者中，LDAEP 与 DAT 之间存在相关性的趋势（r=0.65；P=0.057），提示低 5-HT 能活性可能与 PD 中的多巴胺缺乏有关。
我们的结果支持未经治疗的 PD 中 5-HT 能传递减少的假设，并表明低 5-HT 能活性可能与 PD 中的多巴胺病理学有关。这可能与 PD 中高抑郁症患病率有关。
