1-甲基-4-苯基-1,2,3,6-四氢吡啶对食蟹猴嗅球多巴胺能神经元的影响

目的 建立食蟹猴1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)帕金森病系统性模型,探讨嗅球中多巴胺（DA）及多巴胺/cAMP调节磷蛋白（DARPP32）的表达情况。
方法 3只成年健康食蟹猴,静脉注射MPTP,建立帕金森病系统性模型,取出嗅球,切片,免疫组织化学染色DA和DARPP32,摄片并观察DA和DARPP32在食蟹猴嗅球中的分布及表达情况,采用Image Pro-Plus软件,半定量分析模型组和正常组之间DA和DARPP32的表达差异。 结果 食蟹猴嗅球中DA和DARPP32神经元集中分布于突触小球层,DA神经纤维分布于突触小球层,而DARPP32神经纤维分布于嗅球各层,以突触小球层（GL）和外网状层（EPL）最为密集。MPTP损伤后,与正常对照组比较,DA和DARPP32神经元及神经纤维均减少,以DA神经元及神经纤维减少明显。 结论 食蟹猴嗅球中DA神经元和神经纤维分布于突触小球层。食蟹猴MPTP帕金森病系统性模型的嗅球DA能神经元和纤维明显减少,可能与帕金森病嗅觉障碍有关。     

人参皂甙Rb1抑制1-甲基-4-苯基-1,2,3,6-四氢吡啶所致的内质网应激对多巴胺能神经元的保护作用

目的:研究内质网应激反应在1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)所致帕金森病(PD)小鼠模型黑质区多巴胺能神经元凋亡的作用.方法:将小鼠随机分为MPTP模型组、Rb1干预剂组和对照组.观察行为学,免疫组织化学和免疫蛋白印迹法观察黑质酪氨酸羟化酶(TH)、葡萄糖调节蛋白78 (GRP78)、半胱氨酸蛋白酶-12 (caspase-12)和半胱氨酸蛋白酶-3 (caspase-3)的表达.结果:与对照组相比,模型组小鼠出现典型PD症状,TH阳性神经元明显丢失、蛋白水平下降,GRP78、caspase-12、caspase-3阳性细胞及蛋白水平增加;经人参皂甙Rb1处理后,上述变化均减轻.结论:内质网应激(ERS)在MPTP诱导的PD小鼠模型多巴胺能神经元凋亡中可起重要作用,人参皂甙Rb1可通过抑制ERS而对PD小鼠具有一定的神经保护作用.     

帕金森病小鼠黑质多巴胺能神经元凋亡诱导因子核移位的研究

目的探讨帕金森病(PD)小鼠模型黑质凋亡诱导因子(AIF)的核移位情况及其与多巴胺(DA)能神经元损伤之间的关系。方法采用1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)制备PD小鼠模型,2h、24h、72h后取中脑组织进行酪氨酸羟化酶免疫染色观察黑质DA能神经元的损害情况,AIF免疫组化染色和Western blot方法检测AIF的核移位情况。结果与对照组比较,PD组小鼠黑质DA能神经元数量随时间呈递减趋势,并出现AIF核移位,2h时达高峰,之后随时间呈下降趋势。结论AIF核移位是PD小鼠黑质DA能神经元损伤的早期指标,在PD的发病过程中发挥重要作用。     

血管钠肽减轻MPP+所致多巴胺神经元损伤*

 目的：探讨血管钠肽（vasonatrin peptide,VNP）的神经保护效应。方法：原代培养取自小鼠中脑腹侧的多巴胺神经元,暴露于1-甲基-4-苯基吡啶离子（1-methyl-4-phenylpyridinium,MPP+）。采用细胞活力分析和免疫荧光染色评价VNP对MPP+神经毒性的影响,并应用多种阻断剂和激动剂探讨VNP神经效应的机制。结果：MPP+造成多巴胺神经元损伤,VNP增强多巴胺神经元的细胞活力,增加神经元轴突数目和长度。VNP还可抑制MPP+造成的神经元β-微管蛋白III解聚。另外,VNP显著升高细胞内cGMP水平。VNP的效应可以被8-Br-cGMP（一种膜通透性的cGMP类似物）所模拟,被HS-142-1［鸟苷酸环化酶偶联的钠尿肽受体（NPR）的阻断剂］或KT-5823［cGMP依赖性蛋白激酶(PKG)的阻断剂］所阻断。结论：VNP通过NPR/cGMP/PKG通路减轻MPP+的神经毒性,提示VNP可能成为一种新的有效药物,治疗帕金森病的神经退行性病变。     

银杏叶提取物对帕金森病模型小鼠多巴胺能神经元保护作用研究

目的研究银杏叶提取物（GBE）对帕金森病模型小鼠黑质（SN）多巴胺（DA）能神经元的保护作用。方法36只C5,Bk小鼠随机3组,每组12只。其中,帕金森病（PD）模型组的小鼠采用1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）腹腔注射（30mg／kg×5d）诱导PD;GBE预处理组的小鼠于注射MPTP前2h腹腔注射GBE（60mg／kg×8d）;正常对照组的小鼠只注射等体积生理氯化钠溶液。应用免疫组织化学染色观察小鼠黑质致密带（SNzc）酪氨酸羟化酶（TH）免疫反应阳性细胞数量的变化,用高效液相色谱法（HPLC-ECD）检测小鼠纹状体（Str）内DA及其代谢物二羟基苯乙酸（DOPAC）和高香草酸（HVA）含量。结果PD模型组小鼠SN内酪氨酸羟化酶（TH）阳性细胞数量、Str内DA及其代谢产物DOPAC和HVA的含量明显减少（P〈0．01）,GBE预处理组小鼠SN内TH阳性细胞数量、Str内DA及其代谢产物DOPAC和HVA的含量明显增多（P〈0.05）,但仍低于正常对照组（P〈0．01）。结论GBE对MPTP致帕金森病小鼠SNDA能神经元具有明显的保护作用。     

p38MAPK抑制剂对MPTP模型小鼠黑质多巴胺能神经元的保护作用

目的:研究SB239063在1-甲基-4-苯基-1,2,3,6四氢吡啶(MPTP)所致帕金森病(PD)模型小鼠中抑制p38丝裂原激活蛋白激酶(mitogen-activated protein kinase,MAPK)活化对多巴胺(DA)能神经元的保护作用。方法:雄性C57BL/6N小鼠随机分为MPTP(30 mg/kg)模型组;SB239063(5 mg/kg)抑制剂组;SB239063(15 mg/kg)抑制剂组;SB239063(25 mg/kg)抑制剂组。抑制剂组于每次注射MPTP前3 h腹腔注射SB239063;对照组注射与模型组和抑制剂组等量生理盐水和DMSO。采用免疫组织化学和免疫蛋白印迹法观察各组小鼠黑质酪氨酸羟化酶(TH)和磷酸化p38蛋白激酶(p-p38 protein kinase,p-p38MAPK)之间表达变化的关系。结果:模型组小鼠黒质区p38MAPK显著活化,同时伴有TH阳性神经元明显丢失;SB239063 15 mg/kg与25 mg/kg组均可明显减少TH神经元丢失,而5 mg/kg组无显著影响;免疫荧光双标记结果显示p38MAPK与TH阳性神经元存在共表达。结论:p38MAPK对PD模型小鼠中脑黑质多巴胺能神经元丢失可能有重要调控作用,SB239063对多巴胺神经元具有一定的神经保护作用。     

环加氧酶-2对帕金森病模型小鼠黑质多巴胺能神经元的影响

目的　观察COX 2对帕金森病小鼠黑质多巴胺能神经元的影响。方法　选用C5 7BL种系环加氧酶 2 (Cyclooxygenase 2 ,COX 2 )缺陷小鼠 ,腹腔注射 1 甲基 4 苯基 1,2 ,3,6 四氢吡啶 (MPTP)制备帕金森病小鼠模型 ,用免疫组织化学方法。结果　行为学及免疫组织化学观察显示 ,野生型帕金森病小鼠的死亡率明显高于COX 2缺陷杂合子帕金森病小鼠 (P <0 0 1) ;野生型帕金森病小鼠黑质致密部酪氨酸羟化酶 (Ty rosineHydroxylase ,TH)免疫反应阳性神经元数目较杂合子帕金森病小鼠明显减少 (P <0 0 1)。结论　COX 2很可能与帕金森病时黑质多巴胺能神经元的损伤有关     

线粒体转录终止因子蛋白家族的表达以及在MPTP/MPP~+诱导下的表达变化

目的探讨线粒体转录终止因子(MTERFs)蛋白家族在组织和细胞中的表达以及在神经毒素MPTP/MPP+诱导下的表达变化。方法取正常C57BL小黑鼠的脑、肝、肾组织,以及人神经母细胞瘤细胞SH-SY5Y、人心肌细胞HCM、人肝细胞L-02,检测MTERFs的蛋白表达情况;通过MPTP/MPP+构建帕金森病(PD)动物/细胞模型,检测MTERFs的蛋白表达变化情况。结果 MTERFs在小鼠脑中和SH-SY5Y细胞中蛋白表达水平较高;MPTP/MPP+诱导的PD模型中,MTERF3蛋白表达水平明显降低。结论在小鼠脑和SH-SY5Y细胞中,MTERFs表达较高;MPTP/MPP+诱导下MTERF3蛋白表达明显降低,影响了线粒体转录水平,这可能参与了帕金森病发生的过程。     

反义寡核苷酸阻断多巴胺转运体表达的大鼠对MPTP反应性的改变

目的 了解反义寡核苷酸阻断大鼠黑质多巴胺神经元多巴胺转运载体表达的效果,观察阻断后大鼠对神经毒素1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP)反应性的改变.方法 在立体定向仪下埋管至SD大鼠黑质致密部,4组大鼠分别接受反义寡核苷酸、正义寡核苷酸、错义寡核苷酸及生理盐水注射5d,之后接受MFTP注射,进行行为学、病理免疫组化染色观察多巴胺转运载体表达及多巴胺神经元凋亡.结果 大鼠黑质多巴胺转运载体表达(阳性单位,PU)反义寡核苷酸组(PU=6.65±1.67)较生理盐水对照组(PU=12.41±2.46)、正义寡核苷酸组(PU=11.45±1.17)及错义寡核苷酸组(PU=10.35±2.89)明显降低(免疫组化染色面积减少及强度降低)(P＜0.01);阿扑吗啡诱导的大鼠旋转反义寡核苷酸组较其余3组慢(P＜0.05);其余3组间差异无统计学意义(P＞0.05).反义寡核苷酸组黑质200×视野凋亡细胞个数(21.4±5.6)较其他3组(生理盐水组61.6±19.7,正义寡核苷酸组56.5±16.3,错义寡核苷酸组52.2±12.5)明显减少(P＜0.01).结论 反义寡核苷酸能有效阻断大鼠黑质多巴胺转运载体表达,阻断后大鼠对MPTP毒素反应性减弱.     

脑内炎症对黑质多巴胺能神经元的选择性损伤作用

目的 探讨脑内炎症反应对中脑黑质多巴胺能神经元的选择性变性作用.方法 健康SD雄性大鼠10只,随机分为实验组和对照组,实验组行脂多糖(LPS)右侧脑室定位注射,对照组注射生理盐水.注射后48周用免疫组织化学或组织化学法观察黑质多巴胺能、中缝核5-羟色胺能及基底核胆碱能3种不同类型神经元的变性及上述不同脑区小胶质细胞的激活情况.结果 免疫组织化学染色显示,LPS组在黑质、海马、纹状体、中缝核部位均可见到OX6阳性小胶质细胞,说明不同脑区均出现炎症反应.不同类型神经元染色结果显示,LPS组黑质多巴胺能神经元胞体变小、染色变浅、突起减少甚至消失,神经元数量比对照组减少40.1%(P<0.01);5-羟色胺能神经元及胆碱能神经元形态及数量均无明显改变.结论脑室注射LPS导致的脑内炎症反应可选择性引起黑质多巴胺能神经元变性损伤.     

Ability of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and some other pyridine derivatives to cause parkinsonism

Institute of Physiologically Active Substances, Academy of Sciences of the USSR, Chernogolovka, Moscow Region. (Presented by Academician of the Academy of Medical Sciences of the USSR, I. P. Ashmarin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 6, pp. 699–701, June, 1989.     

Relationship between the severity of hypokinesia induced by neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and neurochemical changes in brain structures of C57Bl/6 mice

The dynamics of hypokinesia in male C57Bl/6 mice induced by single administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine was studied on the model of parkinsonian syndrome. The neurochemical effect of this neurotoxin was evaluated at the peak of locomotor disorders. Severe hypokinesia was accompanied by an increase in serotonin content and decrease in the rate of serotonin biodegradation in the striatum, hippocampus, and frontal cortex. The content of dopamine metabolite 3,4-dihydroxyphenylacetic acid and dopamine turnover decreased in the striatum, but increased in the hippocampus and frontal cortex. Norepinephrine content decreased in the hypothalamus and cortex. Aspartate content decreased in the hypothalamus and hippocampus. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 7, pp. 58–61, July, 2008     

Experimental parkinsonian syndrome induced in rats by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine

Laboratory of General Pathology of the Nervous System, Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR. Laboratory of Synthesis of Active Compounds and Laboratory of Psychopharmacology, Research Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 4, pp. 397–401, April, 1988.     

Dopaminergic toxicity of rotenone and the 1-methyl-4-phenylpyridinium ion after their stereotaxic administration to rats: implication for the mechanism of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxicity

The 1-methyl-4-phenyl-pyridinium ion (MPP+) is the four electron oxidation product of the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6 -tetrahydropyridine (MPTP). MPP+ can be formed by the oxidation of MPTP by monoamine oxidase B to the intermediate dihydropyridinium species, MPDP+, which is spontaneously transformed to MPP+. In the present study, MPP+, like the mitochondrial toxin rotenone, inhibited pyruvate-malate respiration in isolated mitochondrial preparations. Moreover, the stereotaxic administration of both MPP+ and rotenone caused damage to the dopaminergic nigrostriatal pathway. These data clearly demonstrate that a mitochondrial toxin, administered stereotaxically, is extremely neurotoxic. The data lend support to the concept that MPTP-induced neurotoxicity may be due to the detrimental actions of enzymatically formed MPP+ on mitochondrial function.     

Participation of brain monoamine oxidase B form in the neurotoxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine: relationship between the enzyme inhibition and the neurotoxicity

A neurotoxin for nigrostriatal dopaminergic neurons, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its oxidized metabolite, 1-methyl-4-phenylpyridine (MPP+), both dose-dependently inhibited rat striatal and forebrain monoamine oxidase (MAO) activity with monoamine oxidase A (MAO-A) selectively reversible (competitive, Ki = 4.5 and 2.0 microM) inhibition. A comparison of the Ki values indicated the affinity of MPP+ for MAO-A to be greater than that of MPTP. MPTP inhibited monoamine oxidase B (MAO-B) with both a reversible (competitive, Ki = 116 microM) and an irreversible time-dependent component, but inhibition by MPP+ was reversible and competitive (Ki = 180 microM). These results, together with previous findings on metabolism of MPTP to MPP+ by brain MAO-B, suggest that MPP+ is a simple inhibitor of MAO-A and MAO-B, but MPTP might be a 'suicide substrate' inhibitor for MAO-B.     

Acute administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine affects the adrenal glands as well as the brain in the marmoset

A parkinsonian syndrome was induced in marmosets by administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) for 4 days. Ten days following the onset of drug administration, brainstem and adrenal tissues were assayed for levels of monoamines and their metabolites. In the brainstem tegmentum, dopamine, its metabolites homovanillic acid (HVA) and dihydroxyphenylacetic acid (DOPAC), and noradrenaline were reduced, whereas 5-hydroxytryptamine (5-HT) levels were elevated, in comparison with untreated controls. In the adrenal gland, 5-HT and adrenaline levels were unchanged, but dopamine and noradrenaline were substantially elevated.     

Conversion of the neurotoxic precursor 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine into its pyridinium metabolite by human platelet monoamine oxidase type B

MPTP (1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine) causes selective and irreversible degeneration of the substantia nigra of human and non-human primates. In the central nervous system, the oxidative metabolism of MPTP to 1-methyl-4-phenyl-pyridinium (MPP+) by monoamine oxidase type B (MAO-B) seems to be a critical feature in the neurotoxic process. We now report that [3H]MPTP is rapidly converted in vitro into [3H]MPP+ by human platelet MAO-B. The formation of [3H]MPP+ in human platelets is prevented by specific MAO-B but not by MAO-A or by 5-hydroxytryptamine uptake inhibitors.     

Count and phagocytic activity of leukocytes in rats with experimental depressive syndrome caused by systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine

Leukocyte count decreased, relative content of neutrophils and monocytes increased, and their phagocytic activity was suppressed in rats with 1-methyl-4-phenyl-1,2,3,4-tetrahydropyridine-induced depressive syndrome at the stage of acute behavioral depression. The severity of behavioral depression inversely correlated with changes in the absolute neutrophil and monocyte counts.     

Partial protection from the dopaminergic neurotoxin N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine by four different antioxidants in the mouse

C57 black mice given a single injection of N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 40 mg/kg, developed marked reduction of striatal dopamine content and loss of dopaminergic neurons in the zona compacta of the substantia nigra. However, pretreatment with any one of four different antioxidants, alpha-tocopherol, beta-carotene, ascorbic acid or N-acetylcysteine, significantly decreased MPTP-induced striatal dopamine loss, and alpha-tocopherol prevented neuronal loss in the substantia nigra. Four chemical analogues of MPTP (cinnamaldehyde, N,N-dimethylcinnamylamine, arecoline and 2-methyl-1,2,3,4-tetrahydro-6,7-isoquinolinediol) were all found to lack dopaminergic nigrostriatal neurotoxicity in the mouse.