Neuropathology of dopamine systems in schizophrenia

描述（由申请人提供）：精神分裂症是一种具有未知病理生理学的毁灭性疾病，影响着世界上1%的人口。以下修订方案中的实验将重点关注精神分裂症（SA1）的基底神经节和多巴胺（DA）病理，并将这些变化与抗精神病药物（APDs）治疗大鼠（SA2）的变化联系起来。我们的初步数据显示，在精神分裂症（SZ）患者死后组织的电镜（EM）研究中，黑质（SN）的DAergic神经元形态和TH+纹状体突触数量异常，APD治疗大鼠的TH+细胞数量减少，类似的结构变化。SA1利用正常对照、典型apd或非典型apd或停药治疗的SZ组织，验证了SZ基底神经节DA系统紊乱的假设。SA2验证了在SZ的SN和腹侧被盖区（VTA）观察到的解剖变化是apd的部分结果的假设，并将确定其生理机制。在这两个目的中，我们将确定所见的形态学改变是否会显示区域差异，这与典型和非典型apd对中脑DA神经元活动的差异影响一致。在这次修订中，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个平行实验。在SA1a中，将在EM水平上分析人类纹状体中DA标记谱的突触组织。在SA1b和SA2a中，将使用SN/VTA中的体视学方法确定Nissl染色和双标记DA转运体（DAT）或DA细胞的选择性标记物SK3的TH+细胞的数量和大小。在SA1c和SA2b的EM水平，将研究亚细胞器的完整性和TH+神经元的突触组织（也标记为DAT或SK3）。使用原位杂交SA1d和SA2e将确定TH的合成是否在转录水平上受到影响。SA1c和SA2d将决定细胞骨架蛋白是否上调。SA1f和SA2e将通过Western blot分析确定神经元中TH的丢失是否由于翻译水平的变化。SA2f将研究APD治疗期间观察到的解剖变化的时间过程，并将这些变化与去极化（DP）阻滞的发展联系起来。SA2g验证了一种假设，即如果阻止DP阻断（单侧纹状体损伤），APD治疗大鼠的SN/VTA神经元不会发生形态学改变。

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).