Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Neuroscience. 2010 Nov 10;170(4):1282-5. doi: 10.1016/j.neuroscience.2010.07.030. Epub 2010 Aug 17.
The healthy brain appears to have an asymmetric dopamine distribution, with higher levels of dopamine in the left than in the right striatum. Here, we test the hypothesis that this neurochemical asymmetry renders the right striatum relatively more vulnerable to the effects of dopaminergic denervation in Parkinson's disease (PD). Using the pegboard dexterity test, we compared motor performance of both hands between healthy subjects (n=48), PD patients with predominantly right-hemispheric dopamine depletion (PD-RIGHT; n=83) and PD patients with more severe left-hemispheric dopamine depletion (PD-LEFT; n=103). All subjects were right-handed. After adjusting for hand-dominance effects, we found that PD-RIGHT patients exhibited a 55% larger difference between right and left dexterity scores than PD-LEFT patients. This effect could be attributed to greater motor dysfunction of the more-affected hand in PD-RIGHT patients, while the less-affected hand performed similarly in both groups. We conclude that the side of symptom onset affects motor dysfunction in PD, and suggest that the non-dominant right hemisphere may be more susceptible to dopaminergic denervation than the dominant left hemisphere.
健康的大脑似乎具有不对称的多巴胺分布，左侧纹状体中的多巴胺水平高于右侧。在这里，我们检验了这样一个假设，即这种神经化学不对称使右侧纹状体在帕金森病（PD）中更容易受到多巴胺能神经支配丧失的影响。使用钉板灵巧度测试，我们比较了健康受试者（n=48）、主要右侧多巴胺耗竭的 PD 患者（PD-RIGHT；n=83）和左侧多巴胺耗竭更严重的 PD 患者（PD-LEFT；n=103）双手的运动表现。所有受试者均为右利手。在调整手优势效应后，我们发现 PD-RIGHT 患者右侧和左侧灵巧度评分之间的差异比 PD-LEFT 患者大 55%。这种影响可能归因于 PD-RIGHT 患者受影响更大的手的运动功能障碍更大，而两组中受影响较小的手表现相似。我们得出结论，症状发作的侧位会影响 PD 中的运动功能障碍，并表明非优势右侧半球可能比优势左侧半球更容易受到多巴胺能神经支配丧失的影响。
