表没食子儿茶素没食子酸酯对MPTP致多巴胺能神经元损伤的保护作用

目的研究表没食子儿茶素没食子酸酯(EGCG)对1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)致帕金森病模型小鼠多巴胺能神经元的保护作用。方法32只雄性C57BL/6小鼠随机分为4组：假手术组腹腔注射等量生理盐水,模型组腹腔注射4次MPTP(16 mg/kg,间隔2 h),EGCG治疗组为MPTP+EGCG(5 mg/kg)组,EGCG正常给药组不做任何处理,每日给予5 mg/kg EGCG。连续给药3周后检测行为学指标,黑质酪氨酸羟化酶(TH)免疫组化染色及高效液相色谱-电化学法测定纹状体内多巴胺及其代谢产物浓度。结果模型组5 min内的自发运动次数(71.4±14.0)下降,而EGCG治疗组自发运动次数(87.9±10.7)提高(P<0.05)。与模型组转杆停留时间(73.5±24.9) s相比,EGCG治疗组转杆停留时间(118.6±31.2) s延长(P<0.05)。形态学结果显示,EGCG治疗组黑质TH阳性神经元与模型组相比,数量明显增多。模型组纹状体内多巴胺(DA)及其代谢产物3,4-双羟苯乙酸(DOPAC)和高香草酸(HVA)浓度显著降低,而EGCG治疗组DA、DOPAC和HVA浓度虽有一定程度升高,但无统计学差异。结论EGCG改善MPTP致帕金森病模型小鼠的运动能力下降,对黑质多巴胺神经元有保护作用。     

MPTP诱导多巴胺能神经元凋亡规律和尼古丁神经保护作用的研究

目的:探讨1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)诱导小鼠多巴胺能神经元凋亡的规律以及尼古丁对其的保护作用。方法:取28只小鼠(PD组)腹腔注射MPTP 30 mg/(kg·d),共7 d,建立小鼠帕金森病模型;取4只小鼠(Nic组)腹腔注射尼古丁(2 mg/kg,每天5次,共17 d);取4只小鼠(Nic+MPTP组)给予尼古丁预处理和MPTP;取4只小鼠(对照组)仅给予等量生理盐水。应用酪氨酸羟化酶(TH)免疫组织化学染色和TUNEL染色,观察各组黑质多巴胺能神经元数目改变和凋亡细胞的变化规律。结果:慢性MPTP处理过程中,小鼠黑质TH阳性细胞数逐渐减少,于MPTP注射第3天开始出现TUNEL阳性细胞,并于第8天达到高峰。与PD组相比,Nic+MPTP组TH阳性细胞丢失和TUNEL阳性细胞增多的程度显著降低(P<0.05)。结论:采用慢性MPTP处理的模式,可诱导小鼠黑质多巴胺能神经元凋亡;尼古丁对这类神经元具有明显保护作用。     

肌苷对帕金森病模型小鼠行为学及纹状体多巴胺水平的影响

目的:观察肌苷对1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP)致帕金森病模型小鼠行为学及多巴胺水平的影响。方法:实验在解放军第四军医大学实验动物中心实验室和基础部神经生物教研室实验室进行。取雄性C57BL小鼠20只,腹腔注射MPTP建立C57BL小鼠帕金森病模型,随机分为生理盐水组和肌苷组各10只,通过行为学检测、免疫组织化学和荧光分光光度法,观察肌苷对小鼠帕金森病模型的行为学表现、黑质多巴胺神经元和纹状体酪氨酸羟化酶免疫反应阳性(tyrosinehydroxylase-immunoreactive,TH-ir)神经纤维以及纹状体多巴胺水平的影响。结果:给予肌苷后帕金森病小鼠行为学计数和黑质多巴胺神经元数目与生理盐水组相比差异无显著性意义,但纹状体TH-ir神经纤维密度和纹状体多巴胺水平升高,给予肌苷后纹状体多巴胺水平是生理盐水组的2.08倍。结论:肌苷对MPTP所致的帕金森病模型小鼠具有改善自主活动的能力,并且对纹状体内多巴胺水平也产生干预效应。     

哌替啶类衍生物造模帕金森病小鼠的最佳剂量

目的:比较不同剂量哌替啶类衍生物1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methy-4-phenyl-1,2,3,6-tetrahydropyrindine,MPTP)建立的帕金森病小鼠模型对小鼠纹状体多巴胺含量的影响。方法:实验于2003-11/2004-07在北京宣武医院神经生物学实验室完成。选择C57BL/6L小鼠60只,采用不同剂量MPTP建立帕金森病小鼠模型,随机分6组,MPTP40mg/kg皮下注射1次组10只;MPTP20mg/kg腹腔注射,每2h1次,注射3次组10只;MPTP25mg/kg腹腔注射,每2h1次,注射3次组10只;MPTP45mg/kg皮下注射1次组10只;MPTP35mg/kg皮下注射1次组10只;正常对照组10只。采用Lowry法测定纹状体组织中多巴胺含量/蛋白质含量。结果:纳入动物60只,52只进入结果分析,其中8只均在处死前死亡。MPTP使小鼠纹状体多巴胺含量显著性下降。正常对照组多巴胺含量为(136.39±41.61)μg/g;MPTP35,40,45mg/kg皮下注射1次组分别为(107.97±26.92),(85.91±24.60),(74.13±12.49)μg/g,分别是正常对照组的79.16%,62.99%,54.35%;MPTP20,25mg/kg腹腔注射每2h1次,注射3次组分别为(44.90±18.41),(44.30±29.44)μg/g,分别是正常对照组的32.92%,32.48%。5个模型组与正常对照组比较差异均显著(P<0.01)。结论:MPTP20mg/kg腹腔注射每2h1次,注射3次和MPTP40mg/kg皮下注射1次两种模型是对帕金森病不同研究方向的理想模型。     

miR-218-5p改善帕金森病小鼠多巴胺能神经元变性

目的：探索miR-218-5p对1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）诱导的急性帕金森病（PD）模型小鼠黑质多巴胺能神经元的保护作用及其可能机制。方法：18只8周雄性C57小鼠随机分配至MPTP组和PBS组,分别腹腔注射20 mg/kg MPTP或等体积无菌PBS,每隔2 h注射一次,共4次。另将36只8周雄性C57小鼠随机平分为（NC agomir+PBS）组（NCPBS组）、（NC agomir+MPTP）组（NCMPTP组）、（miR-218-5p agomir+PBS）组（218PBS组）、（miR-218-5p agomir+MPTP）组（218MPTP组）,每组9只,分别进行双侧黑质立体定位注射miR-218-5p agomir/NC agomir,3 d后腹腔注射MPTP或PBS。免疫荧光染色和Western blot检测小鼠黑质多巴胺能神经元酪氨酸羟化酶（TH）的表达;荧光定量PCR检测小鼠黑质miR-218-5p和Wnt7a、Ctnnb1、Lef1、Birc5 mRNA的表达。结果：与PBS组相比,MPTP组小鼠黑质miR-218-5p表达显著下降（...     

肌苷对帕金森病模型小鼠行为学及纹状体多巴胺水平的影响

目的：观察肌苷对1-甲基-4-苯基-1，2，3，6-四氢吡啶(1-methyl-4-phenyl-1，2，3，6-tetrahydropyfidine，MPTP)致帕金森病模型小鼠行为学及多巴胺水平的影响。方法：实验在解放军第四军医大学实验动物中心实验室和基础部神经生物教研室实验室进行。取雄性C57BL小鼠20只，腹腔注射MPTP建立C57BL小鼠帕金森病模型，随机分为生理盐水组和肌苷组各10只，通过行为学检测、免疫组织化学和荧光分光光度法，观察肌苷对小鼠帕金森病模型的行为学表现、黑质多巴胺神经元和纹状体酪氨酸羟化酶免疫反应阳性(tyrosine hydroxylase-immunoreactive，TH-ir)神经纤维以及纹状体多巴胺水平的影响。结果：给予肌苷后帕金森病小鼠行为学计数和黑质多巴胺神经元数目与生理盐水组相比差异无显著性意义，但纹状体TH-ir神经纤维密度和纹状体多巴胺水平升高，给予肌苷后纹状体多巴胺水平是生理盐水组的2．08倍。结论：肌苷对MPTP所致的帕金森病模型小鼠具有改善自主活动的能力．并且对纹状体内多巴胺水平也产生干预效应。     

半胱胺通过抗氧化保护帕金森病模型小鼠多巴胺能神经元机制研究

目的观察半胱胺(CS)通过何种机制保护1-甲基-4-苯基1,2,3,6四氢吡啶(MPTP)所致C57BL小鼠多巴胺能神经元的退变。方法取78只SPF级C57BL小鼠,随机分为6组:对照组,MPTP组,CS 20mg/kg+MPTP组,CS 75mg/kg+MPTP组,MPTP+CS 20mg/kg,MPTP+CS 75mg/kg组。MPTP:20mg/kg 5d,CS 2次/d,皮下注射,共14天。反向高效液相色谱-电化学检测纹状体多巴胺的含量;免疫组织化学检测黑质酪氨酸羟化酶阳性细胞,色谱法检测黑质氧化应激指标。结果 CS(20mg/kg)组抑制C57BL小鼠黑质细胞内的ROS、MDA,促进细胞内谷胱甘肽的合成,保护了多巴胺能神经元;CS(75mg/kg)组对黑质多巴胺浓度及多巴胺能神经元数目无改善作用。结论半胱胺抗氧化保护PD小鼠模型的多巴胺能神经元,保护作用与给药剂量密切相关。     

健行颗粒对3种拟帕金森病震颤模型小鼠的干预作用

目的建立肌肉震颤及线粒体功能障碍致3种拟帕金森病震颤小鼠模型,并在此3种模型上观察健行颗粒的药效学作用,探讨其可能的作用机理.方法经氧化震颤素和槟榔碱单次腹腔注射建立小鼠肌肉震颤模型;经MPTP 20mg/kg连续8天腹腔注射建立线粒体损伤致震颤小鼠模型.记录震颤素和槟榔碱模型小鼠震颤持续时间;观察MPTP模型小鼠爬杆行为及自主活动次数的改变,经高效液相色谱测定MPTP模型小鼠纹状体内多巴胺及其代谢产物含量的改变.结果模型组小鼠在给予震颤素或槟榔碱腹腔注射后出现明显震颤,健行颗粒用药组小鼠震颤持续时间较模型组明显缩短;对于MPTP小鼠模型,模型组小鼠爬杆时间延长,运动协调性降低,纹状体内多巴胺含量明显降低,健行颗粒用药组小鼠爬杆时间较模型组明显缩短,自主活动数增加,纹状体内多巴胺含量增高.结论槟榔碱及氧化震颤素均能制备良好的肌肉震颤小鼠模型,健行颗粒能明显减少模型动物肌肉震颤持续时间;对于MPTP腹腔注射拟帕金森小鼠模型,健行颗粒能明显缩短其爬杆时间,增强小鼠自主活动能力,提升小鼠脑纹状体内多巴胺及其代谢产物的含量.     

1-甲基-4-苯基-1,2,3,6-四氢吡啶诱导的帕金森病小鼠模型多巴胺能神经元的缺失方式

目的:观察1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methyl-4-phenyl-1,2,3,6-tetrahydropyritine,MPTP)诱导的帕金森病小鼠急性模型与亚急性模型多巴胺能神经元的缺失方式。方法:实验于2004-11/2005-02在华北煤炭医学院解剖教研室实验室完成。①C57bl小鼠30只,随机分为3组:对照组、急性模型组、亚急性模型组,每组10只。②给予模型组小鼠腹腔注射MPTP,其中亚急性组30mg/(kg·d),连用5d;急性组一天内给药4次,每次20mg/kg,间隔时间一两个小时;对照组给予等量生理盐水。③最后一次注射后24h内取脑,制备石蜡切片。应用原位末端标记法、酪氨酸羟化酶、原癌基因蛋白Bcl-2和细胞色素C蛋白免疫组化染色观察多巴胺能神经元凋亡和改变。结果:30只小鼠均进入结果分析。经免疫组化法发现酪氨酸羟化酶、原癌基因蛋白Bcl-2、细胞色素C蛋白染色阳性细胞数在急性模型组与亚急性模型组之间差别具有显著意义[(22.40±2.06),(68.20±3.61)个/切片;(20.60±2.41),(66.80±2.12)个/切片;(93.0±2.24),(23.2±2.58)个/切片,P<0.001]。④应用原位末端标记法在急性模型组未发现凋亡,而亚急性模型组存在凋亡现象。结论:MPTP诱导的帕金森病小鼠急性模型多巴胺能神经元的缺失可能通过坏死实现,而亚急性模型则是通过凋亡来实现的。     

嗅球部多巴胺能神经元在帕金森病并发嗅觉障碍中的作用

目的:探讨嗅球部多巴胺(DA)能神经元在帕金森病并发嗅觉障碍中的作用。方法:雄性3月龄C57BL/6小鼠,腹腔注射1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methyl-4-phenyl-1,2,3,6-tetrapyridine,MPTP)25mg/kg,每周2次,共持续5周。再以嗅觉障碍行为学方法检测,从上述小鼠中选出帕金森病并发嗅觉障碍小鼠作为实验组,将帕金森病未并发嗅觉障碍小鼠作为实验对照组,另以一组小鼠腹腔注射生理盐水作为生理盐水组。通过免疫组化免疫荧光染色法检测3组小鼠嗅球部DA能神经细胞数量,Western blot实验检测3组小鼠嗅球部酪氨酸羟化酶(TH)蛋白含量。结果:实验组小鼠较实验对照组小鼠嗅球部DA能神经元数量及嗅球部TH蛋白显著减少(P<0.05),实验对照组小鼠嗅球部DA能神经元数量及嗅球部TH蛋白较生理盐水组也显著减少(P<0.05),3组间嗅球部DA能神经元数量及TH蛋白差异有统计学意义(P<0.05)。结论:帕金森病并发嗅觉障碍与嗅球部DA能神经元残存的数量有关。     

自拟复方中药对PD多巴胺能神经元保护作用的研究

目的:观察一种新型自拟复方中药对1-甲-基-4-苯基-1,2,3,6-四氢吡啶(MPTP)所致小鼠帕金森病(PD)的预防作用及其作用机制。方法:C57BL/6J小鼠80只随机分为正常对照组(A组)、中药对照组(B组)、PD模型组(C组)、中药干预组(D组)各20只;给予B、D组中药灌胃,A、C组给予等量生理盐水灌胃,30d后给予C和D组连续5d腹腔注射MPTP造成PD模型,A和B组注射等量的生理盐水。干预结束后连续5d内检测行为学变化(爬竿试验、游泳试验)、纹状体DA浓度及一氧化氮系统(nNOS和iNOS)含量。结果:造模后第3～5天,D组较C组爬杆实验分值明显增高(P<0.05);第1～5天,D组较C组游泳实验分值明显增高(P<0.05,0.01)。造模后第5天,D组DA浓度明显高于C组(P<0.05);D组iNOS mRNA表达量明显低于C组(P<0.05)。结论:中药自拟方对小鼠PD有一定的防治作用,其机制之一可能是通过调节脑内iNOS的表达发挥作用。     

Dopaminergic neurotoxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the mouse: an in vivo electrochemical study

The long-term (i.e., 4-5 months) effects of large doses (3 X 50 mg/kg) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on striatal dopamine-containing afferents were studied in the NMRI strain of mice. Recently improved in vivo electrochemical methods were first used to examine the magnitude, spatial distribution and temporal dynamics of monoamine release initiated via local application of potassium in various regions of the mouse striatum. Immunohistochemical localization of tyrosine hydroxylase and computer-based image analysis were also used to quantitate regional catecholamine-containing nerve fiber densities in the caudate nucleus. The in vivo electrochemical studies showed a statistically significant decrease in the average potassium-evoked release of electroactive species from the MPTP-treated mouse caudate nucleus vs. control. Greater decreases in release were seen in dorsal than in ventral striatum (55% vs. 33%). The average rise time of potassium-evoked release was also significantly prolonged (greater than 50%) after MPTP pretreatment. Histochemical studies showed an overall reduction in the density of dopamine-containing terminals in the drug-treated mice, with a greater loss observed in the more dorsal regions of the caudate nucleus. The experimental data thus support a long-term selective destruction of dorsal vs. ventral dopamine-containing afferents to the striatum by the neurotoxin MPTP in mice.     

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a radical scavenger, prevents 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity in the substantia nigra but not the striatum

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes nigrostriatal dopaminergic neurotoxicity and behavioral impairment in rodents, and previous studies suggest that nitric oxide and reactive oxygen species are involved in MPTP-induced neurotoxicity. The present study examines the effect of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a radical scavenger, on MPTP-induced neurotoxicity in the striatum and substantia nigra pars compacta (SNc) of C57BL/6J mice. MPTP treatment (10 mg/kg s.c. x 4 with 2-h intervals) decreased dopamine levels and tyrosine hydroxylase immunostaining in the striatum and SNc. Pretreatment with edaravone (1 and 3 mg/kg i.p.) significantly reduced the neurotoxicity in the SNc but not striatum. An immunohistochemical study showed that MPTP caused microglial activation both in the striatum and SNc, whereas it increased 3-nitrotyrosine immunoreactivity, an in vivo biomarker of peroxynitrite production, in the SNc but not the striatum. Furthermore, MPTP increased lipid peroxidation product thiobarbituric acid reactive substance in the midbrain, but not the striatum. Edaravone inhibited activation of the microglia and the increased 3-nitrotyrosine immunoreactivity in the SNc but not the striatum, and it also inhibited thiobarbituric acid reactive substance levels in the midbrain. Behavioral analyses showed that edaravone improved MPTP-induced impairment of locomotion and Rotorod performance. These results suggest that edaravone protects against MPTP-induced neurotoxicity in the SNc by blocking the production of reactive oxygen species or peroxynitrite and imply that dopaminergic degeneration in the SNc may play an important role in MPTP-induced motor dysfunction of mice.     

Deprenyl antagonizes acute lethality of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in mice

In Charles River CFW mice, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) caused lethality with an LD50 of 53.8 mg/kg s.c. In mice pretreated with deprenyl, no lethality occurred with MPTP doses up to 110 mg/kg s.c. MPTP alone at doses of 30 to 90 mg/kg s.c. caused marked salivation, licking and grooming, hyperlocomotion, hyperreactivity and convulsions during the 1st hr, followed by depression, continued salivation and respiratory distress at 2 to 3 hr and at longer times, with death occurring at the higher doses. In deprenyl-pretreated mice, MPTP produced only mild and transient effects. 1-Methyl-4-phenylpyridinium (MPP+) was more potent in causing lethality than was MPTP, and deprenyl did not affect its lethality. MPTP lethality was not antagonized by EXP 561 [4-phenyl-bicyclo-(2,2,2)octan-1-amine hydrochloride monohydrate], an uptake inhibitor that prevented the neurotoxic effects of a lower dose of MPTP on striatal dopamine and cortical norepinephrine neurons. In addition to deprenyl, other monoamine oxidase (MAO) inhibitors effective in inhibiting MAO-B (MD 240928 (R-3-[4-((3-chlorophenyl)methoxy)phenyl]-5-[(methylamino)methyl]-2- oxazolidinone methanesulfonate) and pargyline) protected against MPTP-induced lethality, but LY 51641 (N-[2-(o-chlorophenoxy)ethyl]cyclopropylamine hydrochloride) (a selective inhibitor of MAO-A) did not. The protective effect of deprenyl against MPTP-induced lethality was dose-dependent over a dose range of 0.01 to 10 mg/kg; in this range deprenyl inhibited MAO type B (MAO-B) in brain and liver. A 10-mg/kg i.p. dose of deprenyl antagonized MPTP-induced lethality as long as 14 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

链脲佐菌素诱导C57BL/6小鼠糖尿病瘙痒模型的建立

[目的]探讨链脲佐菌素(streptozotocin , STZ)诱导C57BL/6小鼠糖尿病瘙痒模型的最佳剂量.[方法]24只雄性8周C57BL/6野生型小鼠,体重20～28 g,随机分为四组: A组(对照组)单次腹腔注射等剂量柠檬酸钠溶液 10 mL/kg,pH=4.5;B组STZ单次大剂量腹腔注射STZ 160 mg/kg;C组STZ腹腔注射40 mg/kg,连续注射5 d,每次给药时间间隔24 h;D组STZ两次中剂量注射,腹腔注射STZ 85 mg/kg+65 mg/kg,两次间隔时间24 h.从给药前4周开始,A组正常饮食,B、C、D组高脂饮食喂养至实验结束.注射STZ前1 d、注射STZ后1、2、3、4周测定动物的空腹血糖(FBG)、体重,采用录像记录30 min搔抓次数.[结果]与A组相比,B、C、D组造模后血糖升高并在不同时间点达到糖尿病标准(>200 mg/dL)(P<0.05),B组体重较A、C、D组下降(P<0.05),D组在STZ注射后第2、3周搔抓次数较A、B、C增多(P<0.05).[结论]腹腔分两次、间隔24 h注射STZ 85 mg/kg+65 mg/kg并配合高脂饮食是建立糖尿病并发瘙痒小鼠模型的合适方法.     

脂多糖联合D-氨基半乳糖诱导急性重症肝炎小鼠模型的建立

目的：建立存活时间较长的急性重症肝炎小鼠模型。方法：将50只BALB／c小鼠平均分成5组,其中A、B、C、D4组为实验组,E组为对照组;实验组分别给予D氨基半乳糖（D-GaIN）和脂多糖（LPS）,剂量分别为800mg／kg和10μg／kg、500mg／kg和10μg／kg、500mg／kg和5μg／kg、300mg／kg和5,ug／kg,用生理盐水稀释至1mL,行腹腔注射;对照组E腹腔注射生理盐水2mL。以12h死亡率、24h死亡率及肝组织学改变为观察指标。结果：A、B、C、D及E组小鼠12h死亡率分别为80％％、30％、10％、0和0;24h死亡率分别为909,6、60％、30％、0和0;A和B组小鼠肝组织学均呈急性重症肝炎表现,C组中有5只小鼠肝组织学符合重症肝炎的表现,而该组其余小鼠及D组所有肝组织学虽有炎症改变,但达不到重症肝炎的程度,E组肝组织学表现正常。结论：LPS10ug／kg联合D～GaIN500mg／kg可成功建立12h存活率较高的急性重症肝炎小鼠模型。     

D(1) dopamine receptor agonists are more effective in alleviating advanced than mild parkinsonism in 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine-treated monkeys

Selective D(1) dopamine receptor agonists exert antiparkinsonian effects in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) monkey model of Parkinson's disease and in human Parkinson's disease. Motor impairment in idiopathic Parkinson's disease progresses from mild to severe, but the therapeutic potential of D(1) dopamine receptor agonists in early and advanced stages of parkinsonism is not known. To compare the effectiveness of D(1) agonists at different levels of impairment, we developed a model of mild and advanced parkinsonism in nonhuman primates and a rating scale that differentiated the two models. D(1) dopamine receptor agonists (SKF 81297, dihydrexidine) and D(2) dopamine receptor agonists [quinelorane, (+)-PHNO were administered to monkeys (Macaca fascicularis) displaying either mild parkinsonism (two doses of 0.6 mg/kg i.v. MPTP 1 month apart) or advanced parkinsonism (three doses of 0.6 mg/kg i.v. MPTP within 10 days). In normal monkeys (n = 3), SKF 81297 and dihydrexidine did not promote increased motor activity. In advanced parkinsonism (n = 4), D(1) and D(2) dopamine agonists effectively reversed the motor deficits. In contrast, the therapeutic benefits of D(1) agonists SKF 81297 and dihydrexidine were relatively limited in mild parkinsonism (n = 4). The D(2) agonists quinelorane and (+)-PHNO alleviated some symptoms in mild parkinsonism but also reduced balance and induced more dyskinesias than did D(1) agonists. Mild and advanced parkinsonism in nonhuman primates can be produced with fixed dosing regimens of MPTP. Based on the therapeutic efficacy and side effect profiles derived from these models, D(1) agonists are more promising for the treatment of advanced than of mild Parkinson's disease.