Neuropathology of dopamine systems in schizophrenia

描述（由申请人提供）：精神分裂症是一种毁灭性的疾病，病理生理学未知，影响世界人口的1%。以下修订提案中的实验将重点关注精神分裂症（SA 1）中的基底神经节和多巴胺（DA）病理学，并将这些变化与接受抗精神病药物（APD）治疗的大鼠中发生的变化联系起来（SA 2）。我们的初步数据显示，在黑质（SN）DA能神经元的形态异常和TH+纹状体突触的数量在电子显微镜（EM）的研究与精神分裂症（SZ），类似的结构变化和减少TH+细胞的数量在APD治疗的大鼠死后组织。SA 1使用正常对照、用典型或非典型APD或停药治疗的SZ的组织检验SZ基底神经节中DA系统受到干扰的假设。SA 2检验了以下假设：在SZ的SN和腹侧被盖区（VTA）中观察到的解剖学变化部分是APD的结果，并将确定相关的生理机制。在这两个目标中，我们将确定所看到的形态学改变是否会显示与典型和非典型APD对中脑DA神经元活性的差异效应一致的区域变化。在本修订版中，我们修改了SN的EM分析，并在人体组织和大鼠（氟哌啶醇或氯氮平或对照组）中增加了3项平行实验。在SA 1a中，将在EM水平上分析人纹状体中DA标记谱的突触组织。在SA 1b和SA 2a中，将使用SN/VTA中的体视学方法确定尼氏染色的TH+细胞的数量和大小，以及用DA转运蛋白（DAT）或DA细胞的选择性标记物SK 3双标记的TH+细胞。在SA 1c和SA 2b中，在EM水平上，将研究亚细胞器的完整性和TH+神经元（也用DAT或SK 3标记）的突触组织。使用原位杂交SA 1d和SA 2 e将确定TH合成是否在转录水平上受到影响。SA 1c和SA 2d将确定细胞骨架蛋白是否上调。SA 1f和SA 2 e将通过使用Western印迹分析确定神经元中TH的损失是否是由于翻译水平的变化。SA 2f将研究APD治疗期间观察到的解剖学变化的时间过程，并将这些变化与去极化（DP）阻滞的发生联系起来。SA 2g检验了以下假设：如果DP阻滞被阻止（单侧纹状体病变），则在APD处理的大鼠中不会发生SN/VTA神经元的形态学改变。

DESCRIPTION (provided by applicant): Schizophrenia is a devastating illness, with unknown pathophysiology, that affects 1% of the world's population. The experiments in the following revised proposal will focus on the basal ganglia and dopamine (DA) pathology in schizophrenia (SA1) and relate these changes to those occurring in rats treated with antipsychotic drugs (APDs) (SA2). Our preliminary data shows abnormalities in morphology of DAergic neurons in the substantia nigra (SN) and in the number of TH+ striatal synapses in electron microscopic (EM) studies of postmortem tissue from subjects with schizophrenia (SZ), similar structural changes and a decrease in number of TH+ cells in rats treated with APD. SA1 tests the hypothesis that the DA system is perturbed in the basal ganglia of SZ, using tissue from normal controls, SZ treated with typical or atypical APDs or off-drug. SA2 tests the hypothesis that anatomical changes observed in SN and ventral tegmental area (VTA) of SZ are the results, in part, of APDs, and will determine the contributing physiological mechanisms. In both aims, we will determine if the morphological alterations seen will show regional variations that are consistent with the differential effects of typical and atypical APDs on the activity of midbrain DA neurons. In this revision, we have modified the EM analysis of the SN and added 3 parallel experiments in both the human tissue and rats (treated with haloperidol or clozapine or controls). In SA1a the synaptic organization of DA labeled profiles will be analyzed in the human striatum at the EM level. In SA1b & SA2a, the number and size of Nissl stained, and TH+ cells double labeled with the DA transporter (DAT), or a selective marker of DA cells, SK3, will be determined using stereological methods in the SN/VTA. In SA1c & SA2b at the EM level, the integrity of subcellular organelles and the synaptic organization to the TH+ neurons (also labeled with DAT or SK3) will be studied. Using in situ hybridization SA1d & SA2e will determine if TH synthesis is affected at the level of transcription. SA1c & SA2d will determine if cytoskeletal proteins are upregulated. SA1f & SA2e will determine if the loss of TH in neurons is due to changes at the translational level by using Western blot analysis. SA2f will study the time course of the anatomical changes observed during APD treatment and relate these changes to the development of depolarization (DP) block. SA2g tests the hypothesis that morphological alterations in SN/VTA neurons will not occur in rats treated with APD if DP block is prevented (with a unilateral striatal lesion).