Rinne U K, Rinne J O, Rinne J K, Laakso K, Lönnberg P
Acta Physiol Pharmacol Latinoam. 1984;34(3):287-99.
Parkinson's disease is characterized by a deficiency of dopamine in the nigrostriatal system. However, changes in dopamine neurons were found also outside the extrapyramidal system, showing that there is a more general brain defect than just the loss of substantia nigra dopamine neurons. With regard to the behavior of striatal D-2 receptors it was possible to divide parkinsonian patients into two subgroups, because either a decrease or an increase in the number of D-2 receptors was found. Clinically, the patients with a decreased number of striatal D-2 receptors were more disabled and had lost the beneficial response to levodopa. D-3 receptor binding sites were decreased in the parkinsonian striatum. Changes in the cholinergic-muscarinic receptors in the striatum seem to be related to changes in D-2 receptors, and muscarinic receptor supersensitivity was found in cortical areas. GABA receptor binding was decreased in the substantia nigra. In the parkinsonian brain there seems to be supersensitivity of a population of enkephalin receptors (delta) in the striatum and in the limbic system and also a loss of others (mu) in the striatum. Furthermore, the Met-enkephalin content was decreased in the parkinsonian substantia nigra. A decreased concentration of substance P was found in the substantia nigra of all parkinsonian patients and in the putamen of those patients who had not received levodopa treatment. The somatostatin level was decreased in the frontal cortex in relation to dementia. There are thus multiple neuronal disturbances in the parkinsonian brain, although those of the nigrostriatal dopamine neurons seem to be the greatest and are more closely related to parkinsonian clinical features and to treatment responses.
帕金森病的特征是黑质纹状体系统中多巴胺缺乏。然而，在锥体外系统之外也发现了多巴胺神经元的变化，这表明存在一种比仅仅黑质多巴胺神经元丧失更普遍的脑缺陷。关于纹状体D-2受体的行为，有可能将帕金森病患者分为两个亚组，因为发现D-2受体数量要么减少要么增加。临床上，纹状体D-2受体数量减少的患者残疾程度更高，并且对左旋多巴失去了有益反应。帕金森病纹状体中的D-3受体结合位点减少。纹状体中胆碱能毒蕈碱受体的变化似乎与D-2受体的变化有关，并且在皮质区域发现了毒蕈碱受体超敏反应。黑质中的GABA受体结合减少。在帕金森病脑中，纹状体和边缘系统中似乎存在一群脑啡肽受体（δ）超敏，并且纹状体中其他一些受体（μ）丧失。此外，帕金森病黑质中的甲硫脑啡肽含量降低。在所有帕金森病患者的黑质以及未接受左旋多巴治疗的患者的壳核中发现P物质浓度降低。与痴呆相关的额叶皮质中生长抑素水平降低。因此，帕金森病脑中存在多种神经元紊乱，尽管黑质纹状体多巴胺神经元的紊乱似乎最为严重，并且与帕金森病临床特征和治疗反应更密切相关。
