蛋白酶体功能与帕金森病相关性实验研究

目的 观察蛋白酶体抑制剂诱导大鼠黑质多巴胺能神经元α-突触核蛋白（α-synuclein，α-Syn）的表达及聚集．探讨蛋白酶体功能在帕金森病（PD）发病中的作用机制。方法采用立体定向将蛋白酶体抑制剂Lactacystin注射至大鼠黑质部位。以免疫荧光法观察黑质区多巴胺能神经元变性缺失，并应用免疫荧光双标法观察多巴胺能神经元内蛋白聚集的包涵体及其主要成分α-Syn的表达．然后通过原位杂交分析α-Syn mRNA表达及Western印迹法检测黑质α-Syn表达量改变。结果注射Lactacystin第7天大鼠开始出现自发性活动减少．阿扑吗啡尚可诱导出旋转行为；3周后患侧黑质部位酪氨酸羟化酶（TH）阳性细胞明显减少。TH与硫磺素、硫磺素与α-Syn复合染色呈阳性。α-Syn mRNA表达量升高，蛋白表达水平增加。结论Lactacystin诱导大鼠黑质细胞α-Syn表达升高并出现蛋白聚集可能是导致PD发病的机制之一。     

蛋白酶体抑制剂诱导多巴胺能神经元变性伴包涵体形成

目的 观察蛋白酶体抑制剂诱导黑质多巴胺(DA)能神经元变性伴胞浆内包涵体形成，探讨蛋白酶体功能在帕金森病发病机制中的作用。方法将蛋白酶体抑制剂Lactacystin立体定向注射至大鼠黑质部位。免疫荧光观察黑质区DA神经元变性缺失及胶质细胞变化。免疫荧光双标法观察DA能神经元内蛋白聚集的包涵体及其主要成分α-共核蛋白(α-synuclein)、Parkin和泛素(ubiquitin)的表达。同时观察。DA能神经元发生细胞凋亡。结果注射Lactacystin第7天大鼠开始出现自发性活动减少，阿扑吗啡可诱导出旋转行为；3周后黑质部位酪氨酸羟化酶(TH)阳性细胞减少，呈剂量依赖性；小胶质细胞增生明显。TH与硫磺素、硫磺素与α-synuclein、硫磺素与Parkin、以及硫磺素与ubiquitin复合染色呈阳性；TH与TUNEL双染亦呈阳性。结论Lactacystin对多巴胺能神经元具有毒性作用，且导致蛋白聚集，包涵体形成。蛋白酶体功能异常可能在帕金森发病机制中起重要作用。     

蛋白酶体抑制剂诱导大鼠运动行为改变的研究

目的 观察蛋白酶体抑制剂诱导大鼠黑质变性及大鼠运动行为改变,探讨蛋白酶体功能下降在帕金森病发病机制中的作用.方法 将蛋白酶体抑制剂立体定向注射入大鼠左侧黑质致密部,对照组注射等体积的生理盐水.观察大鼠自主行为和阿朴吗啡诱导的旋转行为的改变.开野实验观察大鼠自发运动行为改变.免疫组织化学法观察黑质致密部及纹状体内酪氨酸羟化酶的表达.结果 Lactacystin组大鼠给药一周后出现自发性活动减少,动作缓慢,震颤、对外界刺激不自主竖毛,且症状逐步加重;阿朴吗啡可诱导出向健侧的旋转运动.开野实验中,Lactacystin组大鼠自发运动行为出现改变.三周后黑质部位酪氨酸羟化酶免疫阳性细胞及纹状体内酪氨酸羟化酶免疫阳性神经纤维减少.结论 蛋白酶体抑制剂Lactacystin单侧黑质致密部微量注射可以诱导大鼠黑质变性并出现运动行为改变,蛋白酶体抑制剂在帕金森病动物模型制备上有潜在价值,蛋白酶体功能下降可能在帕金森病发病机制中起重要作用.     

应用蛋白酶体抑制剂Lactacystin建立有Lewy体的帕金森病大鼠模型

目的建立符合帕金森病(PD)病理特征———黑质细胞有Lewy体的PD大鼠模型。方法分别在大鼠一侧黑质致密部注射蛋白酶体抑制剂Lactacystin8mg(Lactacystin组)、等体积生理盐水(NS组)和6-羟基多巴胺(6-OHDA组)12mg;观察大鼠自主行为和阿朴吗啡诱导的旋转行为;光镜下观察中脑组织学改变;应用免疫组化染色观察黑质细胞α-synuclein表达和酪氨酸羟化酶(TH)阳性细胞数;测定纹状体区多巴胺和高香草酸含量。结果NS组大鼠未见行为异常;Lactacystin组大鼠出现进行性的运动迟缓、少动、震颤、头向健侧倾斜,注射阿朴吗啡后出现向健侧旋转运动;给药后3周黑质部TH阳性细胞数较NS组减少了83.29%(P<0.01),部分黑质细胞内出现α-synuclein免疫反应呈强阳性的Lewy体;纹状体多巴胺和高香草酸含量(154.82±37.17,98.66±18.81)较NS组明显减少(822.87±131.25,617.77±95.74)(均P<0.01);6-OHDA组大鼠出现与Lactacystin组类似的行为变化,黑质细胞亦显著减少,但未见Lewy体。结论利用蛋白酶体抑制剂Lactacystin阻碍α-synuclein的降解可以建立有Lewy体的PD大鼠模型。     

同型半胱氨酸对多巴胺神经元的影响及其机制研究

目的研究同型半胱氨酸（homocysteine，Hcy）对帕金森病（PD）模型动物的影响及其机制。方法将63只大鼠随机分成3组，即吡咯烷二硫代氨基甲酸盐（PDTC）组27只、生理盐水对照组27只、假手术组9只。分别在实验前1h腹腔注射PDTC或生理盐水，以后每天1次，连续注射7d，通过脑立体定向注射6-羟多巴胺（6-OHDA）建立大鼠PD模型，2h后同侧脑立体定向注射Hcy或生理盐水，采用TUNEL法、免疫组化技术，选择实验后1d、7d及14d为研究时点，观察黑质多巴胺神经元数量、形态改变，黑质细胞凋亡数，以及黑质细胞NF-κB p65的阳性细胞数的变化。结果（1）局部注射Hcy能明显增加6-OHDA引起的黑质多巴胺神经元变性；（2）局部注射Hcy能明显增加6—OHDA引起的黑质细胞凋亡；（3）局部注射Hcy能明显增加黑质细胞NF—κB p65阳性细胞数；（4）PDTC可抑制Hcy和（或）6-0HDA引起的NF—κB p65活化，减少黑质细胞凋亡，增加多巴胺神经元数目。结论NF—κB p65的激活是Hcy促进6-OHDA引起的黑质多巴胺神经元变性及黑质细胞凋亡机制中的重要因素之一，PDTC可显著抑制NF—κB p65的活化，多巴胺神经元变性和黑质细胞凋亡。     

凝血酶诱导的小胶质细胞激活促进多巴胺能神经元变性

目的探讨凝血酶（Thrombin）诱导小胶质细胞（Micoglia）激活与黑质多巴胺能神经元变性的关系。方法采用立体定向术注射凝血酶至大鼠黑质,在不同时间点观察酪氨酸羟化酶（tyrosine hydroxylase,TH）神经元的表达及小胶质细胞的激活情况;同时检测黑质NO量及iNOS mRNA表达。结果（1）凝血酶注入大鼠黑质导致明显的黑质多巴胺能神经元变性,呈时间依赖性,TH阳性细胞数在第3d开始下降,第7d有大量的TH阳性细胞丢失,与对照侧相比下降达约53％（P〈0．01）;高倍镜下可见胞体皱缩、突起明显缩短或减少;14d时细胞数下降至21％,30d时下降至12％（P〈0．01）。（2）凝血酶注射入黑质4h后小胶质细胞开始呈现为“灌木丛样”或少量呈现“阿米巴样”：12h后小胶质细胞数目明显增加且绝大部分呈现“阿米巴样”;24h后细胞已完全激活,“阿米巴样”细胞达高峰;3d维持高峰;14d后小胶质细胞染色变淡,体积变小,“阿米巴样”细胞数目下降。（3）与对照组相比,iNOSmRNA表达明显上调及NO合成增加（P〈0．05）,并且有iNOS在小胶质细胞表达。结论凝血酶对多巴胺能神经元具有一定的损毁作用,小胶质细胞的激活先于多巴胺能神经元变性,其激活后释放的NO有可能参与多巴胺能神经元变性。     

蛋白酶体抑制剂诱导大鼠黑质变性伴包涵体形成

目的 观察蛋白酶体抑制剂Lactacystin诱导大鼠黑质变性伴包涵体形成及运动行为学的改变,探讨蛋白酶体功能下降在帕金森病(PDl发病机制中的作用. 方法 24只SD大鼠采用随机数字表法分为kactacystin实验组和生理盐水组.每组12只,Lactacystin实验组将蛋白酶体抑制剂Lactacystin立体定向注射人大鼠左侧黑质致密部(SNc).生理盐水组注射等体积生理盐水;观察大鼠自主行为和阿朴吗啡(APO)诱导的旋转行为的改变;Nissl染色法观察SNc病理改变;免疫组化法观察SNc及纹状体酪氨酸羟化酶(TH)和SNc中α-共核蛋白的表达;透射电镜观察SNc超微结构的改变. 结果 Lactacystin实验组大鼠给药7 d后出现自发性活动减少、动作缓慢、震颤、且症状逐步加重.APO可诱导出向健侧的旋转运动;Nissl染色发现Lactacystin实验组左侧SNc神经元数量减少,尼氏体结构松散;免疫组化结果表明21 d后Lactacystin实验组左侧SNc出现变性,TH免疫阳性神经元数量减少,α-共核蛋白表达增强,纹状体内TH免疫阳性纤维数量减少;电镜观察到蛋白质聚集形成的包涵体. 结论 Lactacystin单侧SNc注射可以诱导大鼠黑质变性伴包涵体形成及大鼠行为改变.蛋白酶体功能下降可能在PD发病机制中起重要作用.     

S-甲基异硫脲对脂多糖诱导多巴胺能神经元变性的保护作用

目的　 探讨诱导型一氧化氮合酶 (iNOS)抑制剂S 甲基异硫脲 (S methylisourea ,SMT)对脂多糖(lipopolysaccharide ,LPS)诱导多巴胺 (DA)能神经元变性的保护作用及其机制。 方法　 4 8只大鼠随机分成 4组(n =12 ) :磷酸缓冲液 (PBS)对照组、LPS组、生理盐水治疗对照组和SMT治疗组 ;此 4组又各分成 1,7d两个亚组。立体定向注射 5 μgLPS致大鼠脑黑质建立PD炎症模型 ,采用化学比色法检测 1d亚组黑质内NO释放量以及iNOS活性改变 ;RT PCR检测iNOSmRNA的表达 ;酪氨酸羟化酶 (tyrosinehydroxylase ,TH)免疫组织化学染色观察 7d亚组黑质DA能神经元的损伤情况。结果　 与PBS对照组相比 ,LPS注入黑质导致TH阳性细胞数下降至 35 % (P <0 .0 5 ) ;同时黑质内NO含量 ,iNOS活性及iNOSmRNA表达明显增高 ;SMT治疗组NO释放量 ,iN OS活性及iNOSmRNA表达显著降低 (P <0 .0 1) ;TH阳性细胞数亦明显增多 ,达 70 % (P <0 .0 5 ) ,生理盐水治疗组对此无明显改善。结论　iNOS上调是LPS诱导DA能神经元变性机制中重要的因素之一 ,iNOS特异性抑制剂SMT可以显著抑制LPS诱导DA能神经元变性及iNOSmRNA的高表达     

凝血酶诱导小胶质细胞激活与黑质多巴胺能神经元变性关系的研究

目的探讨凝血酶诱导小胶质细胞激活与黑质多巴胺（DA）能神经元变性的关系。方法采用脑立体定向术将凝血酶注射人大鼠黑质，采用尼氏（Nissl）染色、酪氨酸羟化酶（TH）及特异性小胶质细胞表面补体受体（CR3）单克隆抗体（OX-42）标记免疫组织化学染色，观察凝血酶注射人大鼠黑质后不同时间点TH阳性多巴胺能神经元数量及小胶质细胞的激活情况。结果凝血酶注入黑质4h后小胶质细胞开始呈现“灌木丛样”或少量呈现阿米巴样；12h小胶质细胞数目明显增加且绝大部分呈现阿米巴样；24h已完全激活，“阿米巴样”细胞达高峰；3d维持高峰；14d后小胶质细胞染色变淡，体积变小，阿米巴样细胞数目下降。TH阳性细胞数在第3d开始下降，第7d有大量的TH阳性细胞丢失，与对照侧相比下降达约53％（P〈0．01），高倍镜下可见胞体皱缩、突起明显缩短或减少，14d时细胞数下降至21％，30d时约为12％（P〈0．01）。结论凝血酶对DA能神经元具有一定的损毁作用，小胶质细胞的激活先于DA能神经元变性，其活化可能参与DA能神经元变性。     

蛋白酶体抑制剂诱导帕金森病大鼠模型海马区HSP70表达

目的观察蛋白酶体抑制剂Lactacystin诱导帕金森病大鼠模型海马区HSP70表达。方法将Lactacystin 10μg（2μl）经立体定向仪注射到大鼠（Lactacystin组,n=36）左侧黑质致密部,对照组（n=36）以等体积生理盐水代替;分别在药物注射后24h、3d、5d、7d、9d、11d、14d、18d和21d提取海马标本,通过免疫组化和RT-PCR观察HSP70的表达。结果Lactacystin组大鼠海马区HSP70表达较对照组高,表现为注药24h后表达开始增高,5d达高峰,11d开始减少;且海马区表达分布呈CA3〉CA2〉CA1。结论Lactacystin诱导帕金森病大鼠海马区HSP70表达增高,且呈明显区域性和时间依从性;增加的热休克蛋白可能参与拮抗蛋白酶体抑制毒性而起到神经细胞保护作用。     

c-Jun N-terminal kinase mediates lactacystin-induced dopamine neuron degeneration

Parkinson disease is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta. It has been proposed that dysfunction of the ubiquitin proteasome system plays an important role in the pathogenesis of Parkinson disease, but the mechanisms underlying ubiquitin proteasome system-related neuron degeneration are unknown. Here, we demonstrate that the proteasome inhibitor lactacystin induces phosphorylation of c-Jun N-terminal kinase (JNK) and c-Jun, the release of cytochrome c, activation of both caspase-9 and caspase-3, and sequential apoptosis of dopaminergic neurons in vitro. Most of these effects can be attenuated by the JNK inhibitor SP600125. Furthermore, infusion of lactacystin in rats in vivo also leads to phosphorylation of JNK before nigral neuron loss; chronic administration of SP600125 also blocks this loss. These results indicate that JNK is involved in proteasome inhibition-induced dopaminergic neuron degeneration through caspase-3-mediated apoptotic pathways, suggesting that this kinase may be a therapeutic target for the prevention of substantia nigra pars compacta degeneration in Parkinson disease patients.     

脂多糖对多巴胺能神经元的损毁作用及其机制研究

目的观察脂多糖(1ipopolysaccharide．LPs)对黑质多巴胺(dopamine，DA)能神经元的损毁作用，探讨免疫机制与帕金森病(Parkinsondisease，PD)发病的相关性。方法采用立体定向术将LPS注人大鼠单侧黑质后分别于注射后2、3、4周经腹腔注射阿朴吗啡诱发动物旋转行为；采用高效液相色谱一电化学法(high performanee liquid chromatography，HPLC)测定纹状体和黑质部位DA等单胺类递质含量；采用免疫组化法检测黑质酪氨酸羟化酶(tyrosine hydroxylase，TH)阳性细胞数；采用尼(氏)染色(Nissl)观察小胶质细胞的活化和以双重免疫酶染色法观察小胶质细胞活化和诱导型一氧化氮合酶(inducible nitric oxide，iNOS)合成。结果大鼠单侧黑质注人LPS后2、3、4周，以阿朴吗啡诱发大鼠均出现旋转行为，其损伤侧纹状体和黑质DA及其代谢物含量降低了30%～70%，注射侧的黑质TH阳性细胞数减少，尤以3周和4周为甚．尼(氏)染色和双重免疫酶染色法也分别显示LPS注射侧小胶质细胞活化，同时伴有iNOS合成的增加。结论LPS对DA能神经元具有一定的损毁作用，小胶质细胞的活化及其释放的NO有可能参与该细胞死亡，提示免疫机制与PD的发病可能存在相关性。     

Novel D3 dopamine receptor‐preferring agonist D‐264: Evidence of neuroprotective property in Parkinson's disease animal models induced by 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine and lactacystin

Parkinson's disease (PD), a progressive neurodegenerative movement disorder, is known to be caused by diverse pathological conditions resulting from dysfunction of the ubiquitin‐proteasome system (UPS), mitochondria, and oxidative stress leading to preferential nigral dopamine (DA) neuron degeneration in the substantia nigra. In the present study, we evaluated the novel D3 receptor‐preferring agonist D‐264 in a mouse model of PD to evaluate its neuroprotective properties against both the nigrostriatal dopaminergic toxin 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐ and the proteasome inhibitor lactacystin‐induced dopaminergic degeneration. C57BL/6 male mice either were given MPTP by intraperitoneal injection twice per day for 2 successive days at a dose 20 mg/kg or were microinjected with lactacystin bilaterally (1.25 μg/side) into the medial forebrain bundle (MFB). Pretreatment with D‐264 (1 mg/kg and 5 mg/kg, intraperitoneally, once per day), started 7 days before administration of MPTP or lactacystin. We found that D‐264 significantly improved behavioral performance, attenuated both MPTP‐ and lactacystin‐induced DA neuron loss, and blocked proteasomal inhibition and microglial activation in the substantia nigra (SN). Furthermore, D‐264 treatment was shown to increase the levels of brain‐derived neurotrophic factor (BDNF) and glial cell line‐derived factor (GDNF) in MPTP‐ and lactacystin‐treated mice, possibly indicating, at least in part, the mechanism of neuroprotection by D‐264. Furthermore, pretreatment with the D3 receptor antagonist U99194 significantly altered the effect of neuroprotection conferred by D‐264. Collectively, our study demonstrates that D‐264 can prevent neurodegeneration induced by the selective neurotoxin MPTP and the UPS inhibitor lactacystin. The results indicate that D‐264 could potentially serve as a symptomatic and neuroprotective treatment agent for PD. © 2010 Wiley‐Liss, Inc.     

Protective role of melatonin in domoic acid-induced neuronal damage in the hippocampus of adult rats

Domoic acid (DA), a kainite-receptor agonist and potent inducer of neurotoxicity, has been administered intravenously in adult rats in the present study (0.75 mg/kg body weight) to demonstrate neuronal degeneration followed by glial activation and their involvement with inducible nitric oxide synthase (iNOS) in the hippocampus. An equal volume of normal saline was administered in control rats. The pineal hormone melatonin, which protects the neurons efficiently against excitotoxicity mediated by sensitive glutamate receptor, was administered intraperitoneally (10 mg/kg body weight), 20 min before, immediately after, and 1 h and 2 h after the DA administration, to demonstrate its role in therapeutic strategy. Histopathological analysis (Nissl staining) demonstrated extensive neuronal damage in the pyramidal neurons of CA1, CA3 subfields and hilus of the dentate gyrus (DG) in the hippocampus at 5 days after DA administration. Sparsely distributed glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes were observed in the hippocampus at 4-24 h after DA administration and in the control rats. Astrogliosis was evidenced by increased GFAP immunoreactivity in the areas of severe neuronal degeneration at 5 days after DA administration. Along with this, microglial cells exhibited an intense immunoreaction with OX-42, indicating upregulation of complement type 3 receptors (CR3). Ultrastructural study revealed swollen or shrunken degenerating neurons in the CA1, CA3 subfields and hilus of the DG and hypertrophied astrocytes showing accumulation of intermediate filament bundles in the cytoplasm were observed after administration of DA. Although no significant change could be observed in the mRNA level of iNOS expression between the DA-treated rats and controls at 4-24 h and at 5-day time intervals, double immunofluorescense revealed co-expression of induced iNOS with GFAP immunoreactive astrocytes, but not in the microglial cells, and iNOS expression in the neurons of the hippocampal subfields at 5 days after DA administration. Expression of iNOS was not observed in the hippocampus of control rats. DA-induced neuronal death, glial activation, and iNOS protein expression were attenuated significantly by melatonin treatment and were comparable to the control groups. The results of the present study suggest that melatonin holds potential for the treatment of pathologies associated with DA-induced brain damage. It is speculated that astrogliosis and induction of iNOS protein expression in the neurons and astrocytes of the hippocampus may be in response to DA-induced neuronal degeneration.     

经侧脑室注射脂多糖诱导大鼠黑质部位小胶质细胞激活及多巴胺能神经元损伤的研究

目的观察经脑室注射脂多糖(LPS)后大鼠的黑质部小胶质细胞激活及多巴胺(DA)能神经元的变化,探讨脑内炎性反应在黑质DA能神经元慢性变性过程中的作用。方法健康雄性SD大鼠30只,随机分为生理盐水(NS)对照组和LPS组,分别向大鼠右侧脑室注射20μL NS或50μg LPS,40周后用免疫组织化学方法检测大鼠黑质小胶质细胞是否激活、激活的程度(OX-42及OX-6抗体水平),以及酪氨酸羟化酶(TH)阳性神经元的形态和数量。以Fluoro-Jade B(FJB)染色法检测黑质部位神经元变性情况。结果 (1)NS对照组大鼠黑质部位OX-42阳性小胶质细胞呈静息状态,染色浅。LPS组大鼠黑质部OX-42阳性小胶质细胞呈部分激活状态,染色深。两组大鼠黑质部位均未发现OX-6阳性小胶质细胞。(2)NS对照组大鼠黑质部位有大量深染的TH阳性神经元。LPS组大鼠黑质部位TH阳性染色神经元数目(99.11±20.31)比NS对照组(189.52±12.12)减少47.7%(P<0.01)。(3)两组大鼠黑质部位均未见FJB阳性染色神经元。结论经侧脑室单次注射LPS可能造成大鼠黑质部位小胶质细胞长期慢性激活及DA能神经元慢性迟发性功能性损伤。     

Trisialoganglioside GT1b induces in vivo degeneration of nigral dopaminergic neurons: role of microglia

We recently showed that trisialoganglioside (GT1b) induces cell death of dopaminergic neurons in rat mesencephalic cultures (Chung et al., Neuroreport 12:611-614, 2001). The present study examines the in vivo neurotoxic effects of GT1b on dopaminergic neurons in the substantia nigra (SN) of Sprague-Dawley rats. Seven days after GT1b injection into the SN, immunocytochemical staining of SN tissue revealed death of nigral neurons, including dopaminergic neurons. Additional immunostaining using OX-42 and OX-6 antibodies showed that GT1b-activated microglia were present in the SN where degeneration of nigral neurons was found. Western blot analysis and double-labeled immunohistochemistry showed that inducible nitric oxide synthase (iNOS) was expressed in the SN, where its levels were maximal at 8 h post-GT1b injection, and that iNOS was localized exclusively within microglia. GT1b-induced loss of dopaminergic neurons in the SN was partially inhibited by N(G)-nitro-L-arginine methyl ester hydrochloride, an NOS inhibitor. Our results indicate that in vivo neurotoxicity of GT1b against nigral dopaminergic neurons is at least in part mediated by nitric oxide released from activated microglia. Because GT1b exists abundantly in central nervous system neuronal membranes, our data support the hypothesis that immune-mediated events triggered by endogenous compounds such as GT1b could contribute to the initiation and/or the progression of dopaminergic neuronal cell death that occurs in Parkinson's disease.     

Distribution of nitric oxide synthase positive neurons in the substantia nigra of rats with liver cirrhosis

BACKGROUND: Nitrogen monoxide plays an important role in the physiological activity and pathological process of striatum in substantia nigra, and the nitric oxide synthase in substantia nigra may have characteristic changes after liver cirrhosis. OBJECTIVE: To observe the distribution and forms of nitric oxide synthase (NOS) positive neurons and fibers in substantia nigra of rats with liver cirrhosis. DESIGN: A comparative observational experiment. SETTINGS: Beijing Friendship Hospital; Capital Medical University. MATERIALS: Twenty 4-month-old male Wistar rats (120–150 g) of clean grade, were maintained in a 12-hour light/dark cycle at a constant temperature with free access to standard diet and water. Cryostat microtome (LEICA, Germany); All the reagents were purchased from Sigma Company. METHODS: The experiment was carried out in the Department of Anatomy (key laboratory of Beijing city), Capital Medical University from July 2000 to March 2002. The rats were randomly divided into normal group (n =10) and liver fibrosis group (n =10). Rats in the liver fibrosis group were subcutaneously injected with 60% CCl4 oil at a dose of 5 mL/kg for the first time, and 3 mL/kg for the next 14 times, twice a week, totally 15 times. Liver fibrosis of grades 5–6 was taken as successful models. Whereas rats in the normal group were not given any treatment. Four months after CCl4 treatment, all the rats were anesthetized to remove brain, and frontal frozen serial sections were prepared. The expressions of nitric oxide synthase positive neurons in substantia nigra of rats were observed under inverted microscope. The number and gray scale of cell body of nitric oxide synthase positive neurons in substantia nigra were detected with NADPH-diaphorase staining. MAIN OUTCOME MEASURES: ① Number and gray scale of cell body of nitric oxide synthase positive neurons in substantia nigra; ② Expressions of nitric oxide synthase positive neurons in substantia nigra. RESULTS: All the 20 rats were involved in the analysis of results. ① The nitric oxide synthase positive neurons in substantia nigra were obviously fewer in the liver cirrhosis group than in the normal group (P < 0.01), and the gray scale of the positive cell body was higher in the liver cirrhosis group than in the normal group (P < 0.05). ② Abundant nitric oxide synthase positive neurons were observed in substantia nigra of normal rats, the cell body of nitric oxide synthase positive neurons was clear and transparent, with short own cloudy processes. In substantia nigra of rats with liver cirrhosis, the body of nitric oxide synthase positive neurons were observed shrink obviously, less fibrin than normal. CONCLUSION: Rats with liver cirrhosis may suffer from the physiological dysfunction of neurons due to lack of fibers. The nitric oxide synthase positive neurons in substantia nigra can shrink and reduce.     

重组人促红细胞生成素预处理对帕金森病大鼠胶质细胞源性炎症因子表达的影响

目的探讨重组人促红细胞生成素(rhEPO)预处理对帕金森病(PD)大鼠胶质细胞源性炎症因子表达的影响。方法 40只SD大鼠随机分为4组,A组:右侧纹状体内注射rhEPO 24 h后,同侧黑质内注射6-羟基多巴胺(6-OHDA);B组:右侧纹状体内立体定向注射与rhEPO等量的生理盐水,24 h后同侧黑质内立体定向注射6-OHDA;C组:右侧黑质内立体定向注射6-OHDA;D组:右侧黑质内立体定向注射与6-OHDA等量的生理盐水。4周后采用酶联免疫吸附法检测血清诱导型一氧化氮合酶(iNOS)和肿瘤坏死因子(TNF)-α含量;逆转录(RT)-PCR法检测黑质iNOS和TNF-αmRNA的表达。结果与D组比较,A、B、C组大鼠血清iNOS、TNF-α含量增多,黑质iNOS、TNF-αmRNA表达增高(均P<0.05);与B组和C组比较,A组大鼠血清iNOS、TNF-α含量显著减少,黑质iNOS、TNF-αmRNA表达显著降低(均P<0.05)。结论 rhEPO可能通过抑制黑质TNF-α、iNOS表达,减轻6-OHDA对多巴胺能神经元的毒性损害,具有神经保护作用。