胚胎黑质移植对帕金森病鼠纹状体中多巴胺受体敏感性的影响

大鼠纹状体中多巴胺受体介导的C－fos基因的表达与多巴胺D1受体的超敏现象有关。本实验在鼠胚胎黑质细胞植入帕金森病大鼠模型纹状体后第12周,用免疫组化法检测阿朴吗啡诱发的C－fos蛋白,同时取相邻切片进行酷氨酸羟化酶检测,结果经图像分析发现胚胎黑质移植,能显著减少移植侧纹状体中C－fos的表达量,说明胚胎黑质移植能够纠正多巴胶受体的超敏现象。除此之外,还发现C－fos减少的区域明显超过相邻切片酷氨酸羟化酶免疫阳性区域,表明细胞移植对超敏的多巴胺受体的影响范围大大超过了其诱发宿主残存多巴胺神经元再生的范围。     

帕金森病鼠纹状体内羊膜移植对C-fos表达的影响

目的:观察非多巴胺能组织-羊膜细胞移植是否能纠正帕金森病(PD)鼠纹状体多巴胺(DA)受体的超敏感性。方法:在羊膜细胞植入PD大鼠模型纹状体后第12周,用免疫组化法检测阿朴吗啡诱发的C-fos蛋白。结果:经图像分析,发现成活羊膜细胞移植与死羊膜细胞移植相比,能显著减少移植侧纹状体中C-fos的表达量。结论:成活羊膜细胞移植能够纠正多巴胺受体的超敏现象。而且,多巴胺受体受影响的范围大大超过了细胞移植诱发宿主残存多巴胺神经元再生的范围。     

联合培养胚鼠的黑质及纹状体LGE细胞脑内移植治疗帕金森病大鼠的实验研究

目的　观察并检测胚鼠纹状体外侧节突 (LGE)对多巴胺能 (DA)细胞存活性的促进和营养导向作用。方法　将帕金森病 (PD)模型随机分成四组 :Co -culture组 (n =12 ) ;Cograft组 (n =12 ) ;Solo -VM组 (n =12 ) ;Con trol组 (n =8)。将胚鼠LGE细胞和腹侧中脑组织 (VM )制成细胞悬液 ,植入Control组外的其他各组动物的尾壳核。 2周后进行PD鼠行为学检测 ,连续观察 2 4周 ,继之将各组大鼠处死 ,进行免疫组化染色。结果　Co -culture组和Co - graft组大鼠移植后旋转行为较Solo -VM组大鼠明显减少。CO -culture组和CO - graft组之间大鼠的旋转行为比较 ,无统计学差异。免疫组化观察证实LGE和VM离体培养移植和新鲜移植均能提高DA细胞的存活性 ,增加宿主纹状体内DA纤维重新支配的密度 ,并形成明显的DA细胞团。结论　LGE细胞对VM移植物有明显的营养导向作用 ,并可增强DA细胞的存活 ,促进移值后DA细胞功能持久维持 ,并增加DA细胞再支配的密度     

胚胎多巴胺神经元移植治疗帕金森病的实验研究

目的探讨胚胎多巴胺神经元移植对帕金森病大鼠的治疗作用。方法立体定向注射6-羟多巴胺建立帕金森病大鼠模型,随机分为对照组(n=12)和细胞移植组(n=12)。细胞移植组将荧光染料CM-DiI标记的大鼠胚胎多巴胺神经元立体定向注入帕金森病大鼠纹状体区,对照组于相同部位注入生理盐水。用阿扑吗啡诱导帕金森病大鼠旋转行为评估细胞移植的治疗作用。细胞移植8周后取大脑标本行冷冻切片,荧光显微镜下观察移植细胞在脑内存活情况。结果与对照组比较,移植多巴胺神经元能显著改善阿扑吗啡诱导帕金森病大鼠的异常旋转行为(P0.01)。移植8周后,仅少量多巴胺神经元存活。结论多巴胺神经元移植可短期内改善帕金森病大鼠的运动障碍,但长期疗效不佳,可能与移植多巴胺神经元长期存活率较低有关。     

转基因星形胶质细胞脑内移植治疗帕金森病大鼠的研究

目的　评价酪氨酸羟化酶 (TH)基因转染的星形胶质细胞移植入帕金森病 (PD)模型大鼠脑内后对旋转行为改善作用。方法　用pcDNA3 1/TH质粒转染原代培养的星形胶质细胞 ,采用免疫组化及RT PCR方法检测到TH表达后 ,将转基因的星形胶质细胞移植入PD模型大鼠脑纹状体内 ,观察PD大鼠的旋转行为变化情况。结果　移植后共观察 12周 ,转基因细胞移植组PD大鼠 (n =10 )的旋转行为明显改善 (P <0 0 5 ) ,改善情况在 2～ 8周最显著 ,对照组大鼠 (n =10 )的旋转行为无变化。结论　转基因的星形胶质细胞脑内移植后可短期改善PD大鼠的旋转行为 ,星形胶质细胞有可能作为有效的载体细胞。     

人胎盘间充质干细胞移植治疗帕金森病的实验研究

目的探讨人胎盘间充质干细胞(placenta mesenchymal stem cells,PMSCs)脑内移植对帕金森病(Parkinson’s disease,PD)大鼠的治疗作用。方法在分离、培养、鉴定人胎盘间充质干细胞的基础上,应用6-羟基多巴胺(6-hydroxydopamine,6-OHDA)纹状体注射制作24只帕金森病大鼠模型,随机分为3组,每组8只。A组为空白对照组;B组为生理盐水组;C组为细胞移植组,将已标记CM-Di I的PMSCs移植PD模型大鼠,在移植后4 w取脑组织行冰冻切片,并在荧光显微镜下观察移植细胞的分布情况。采用免疫组织化学方法检测PD大鼠黑质多巴胺能神经元,ELISA检测纹状体多巴胺(dopamine)的含量,并从行为学变化对PD大鼠进行综合评价。结果胎盘组织经酶消化后获得贴壁细胞,倒置显微镜下可见PMSCs形态为梭形,成漩涡样生长,将CM-Di I标记的PMSCs移植到PD大鼠纹状体治疗4 w后,可见细胞散在分布于注射侧脑组织,细胞移植组dopamine含量(7.812±0.46)ng/ml明显高于对照组(4.898±0.32)ng/ml(P<0.05),PD大鼠的旋转行为得到显著改善。结论人胎盘间充质干细胞移植治疗帕金森病大鼠可使其旋转行为得到改善,其机制可能与增加黑质多巴胺能神经元的数量,提高纹状体dopamine含量有关。     

脑内移植骨髓间质干细胞治疗帕金森病模型大鼠的实验研究

目的 探讨骨髓间质干细胞(mesenchymal stem cells,MSCs)移植治疗帕金森病(parkinson's disease,PD)大鼠的可行性及可能的机制.方法 移植Brdu标记的MSCs到模型大鼠的纹状体内.术后4个月中,定期对大鼠进行旋转行为学实验测试.并分别在术后2周和4个月时进行脑内针道处及移植区免疫组化检测TH和Brdu的表达.结果 Brdu标记的MSCs移植到模型大鼠的纹状体内,术后2周时移植针道处及针道周围可见Brdu阳性外源MSCs,并有外源性细胞表达TH,术后4个月时移植针道内仍可以看到MSCs存活.MSCs移植的PD模型大鼠症状较PBS注射组行为学明显改善.结论 移植MSCs到大鼠PD模型的纹状体内能成活,且分化细胞能表达TH蛋白,大鼠PD模型行为学症状明显改善.     

牛嗜铬细胞脑内移植可减少帕金森病样大鼠药物诱发的旋转行为

目的观察牛嗜铬细胞移植于PD样大鼠脑内的存活及功能。方法用6－OHDA损毁大鼠一侧黑质细胞制成偏侧PD样大鼠模型。在右侧纹状体内植入约2万个牛嗜铬细胞悬液。记录阿朴吗啡诱发大鼠的旋转行为。实验结束后取大鼠脑做组织形态学检查。结果大鼠在移植后阿朴吗啡诱发的旋转行为得到明显纠正（P<0．001）。移植后12周荧光组化显示移植区有大量SPG阳性细胞，其形态类似在正常肾上腺髓质内的嗜铬细胞的形态。结论脑内移植牛嗜铬细胞可改善PD样大鼠药物诱发的旋转行为；提示牛嗜铬细胞在移植12周后仍能在大鼠脑纹状体内存活。     

成年大鼠脑内5-HT能神经纤维向胎鼠脑皮层移植物内投射的研究

目的:探讨大鼠胎脑皮层组织同种移植后的存活情况,以及宿主脑组织与移植物之间是否能建立神经纤维联系.方法:移植受体(宿主)为正常雄性成年Wistar大鼠,移植供体取自胎龄15～17d的Wistar孕鼠.在移植手术后不同时间取脑切片,用ABC法进行免疫组织化学染色,显示5-HT能神经纤维及其在宿主脑内和移植物中的分布情况.结果:同种胎鼠脑皮层组织移植后存活率为30%,ABC法显示有5-HT能神经纤维从宿主脑组织长入移植物中.结论:同种胎脑皮层组织移植后移植物与宿主脑组织可以建立神经纤维联系.     

人羊膜上皮细胞移植治疗帕金森病模型大鼠的疗效评价

目的观察原位移植人羊膜上皮细胞(Human amniotic epithelial cells,hAECs)对帕金森病(Parkinson’s disease,PD)模型大鼠的疗效及其在体内的存活与分化。方法方法采用胰蛋白酶消化法分离hAECs,流式细胞术分析表型。30只雌性Wistar大鼠随机分为假手术组、模型组和hAECs原位移植组。单侧前脑内侧束(Medial forebrain bundle,MFB)注射6-羟基多巴胺(6-OHDA)建立PD大鼠模型。通过MFB原位移植3×105个hAECs。每周腹腔注射阿朴吗啡诱导旋转观察大鼠的行为变化,免疫荧光染色法检测人细胞核抗原及神经元微管结合蛋白(microtubule-associated protein 2,MAP-2)的表达,免疫组化染色检测酪氨酸羟化酶(Tyrosine hydroxylase,TH)的表达。结果与模型组比较,hAECs原位移植组大鼠旋转次数均明显减少(均P<0.05),行为学改善可至少持续至移植后10 w;免疫荧光染色结果显示,hAECs在原位移植区可存活至少12 w,并表达MAP-2;免疫组化染色显示,原位移植hAECs可上调PD模型大鼠黑质TH表达。结论 hAECs原位移植能改善PD模型大鼠的运动行为,其机制可能与上调黑质TH表达有关。hAECs可在原位移植区分化为多巴胺能神经元样细胞。     

中脑腹侧区细胞移植对帕金森病鼠纹状体多巴胺受体敏感性的影响

大鼠纹状体中多巴胺受体介导的c-fos基因的表达与多巴胺D1受体的超敏现象有关。本实验将鼠胚胎中脑腹侧区细胞植入帕金森病大鼠模型纹状体后第12周,用免疫组化法检测阿朴吗啡诱发的c-fos蛋白,同时取相邻切片进行酪氨酸羟化酶检测。结果经图像分析发现胚胎中脑腹侧区移植,能显著减少移植侧纹状体中c-fos的表达量,说明胚胎中脑腹侧区细胞移植能够纠正多巴胺受体的超敏现象。     

Specific outgrowth from neurons of ventral mesencephalic grafts to the catecholamine-depleted striatum of adult hosts.

Grafts of fetal ventral mesencephalon including substantia nigra have been used to correct some motor deficits produced by unilateral destruction of the dopaminergic nigrostriatal pathway in rats. Histochemical studies have shown that dopaminergic neurons within the graft send processes from the graft to the host neuropil, wherein they form synapses. The results of numerous immunocytochemical studies indicate, however, that a large proportion of neurons in grafts are not catecholaminergic. Whether or not the nondopaminergic neurons in grafts project to the host brain is unknown. The purpose of the present study was to combine immunocytochemistry and retrograde tracing with fluorogold to identify the cell types which project from grafts to the host striatum. Tissue from the ventral mesencephalon of E15 fetuses was placed into the 6-hydroxydopamine denervated striatum of graft recipients. Six weeks to 6 months following transplantation, fluorogold was pressure injected under stereotaxic control immediately adjacent to the ventral mesencephalic grafts; after 4 days CNS tissue was prepared for light microscopic immunocytochemistry. Ventral mesencephalic grafts contained cell bodies immunoreactive for enkephalin, GAD, substance P, and serotonin in addition to those immunoreactive for tyrosine hydroxylase. Some cells of each immunochemically defined type were retrogradely labeled by the fluorogold injection into the host brain. Nevertheless, more catecholaminergic and serotonergic cells projected from grafts to the fluorogold injection site than did other cell types. Since many of the nonmonoaminergic neurons in grafts are probably projection neurons, our results suggest that the extent of neurite outgrowth from grafted cells is influenced by the surrounding target tissue.     

Behavioral and electrophysiological correlates of human mesencephalic dopaminergic xenograft function in the rat striatum

While human fetal xenografts placed into immunocompromised animal hosts have been shown to survive and grow, their ability to function and influence the host tissue has not been fully examined. Therefore, we implanted grafts of human fetal mesencephalic tissue intracranially into rats with unilateral 6-hydroxydopamine lesions of their nigrostriatal dopaminergic innervation and tested the rats behaviorally for reductions in apomorphine-induced rotations. The purpose of this study was to test the ability of these grafts to provide a functional reinnervation by comparing the behavioral changes with the morphology and presence of electrophysiologically active dopaminergic neurons within the graft and with firing rates of host striatal neurons. Adult Sprague-Dawley rats that had been unilaterally lesioned and that showed a stable two peak pattern of apomorphine-induced rotations received grafts of human fetal mesencephalic tissue placed directly into the lesioned striatum. These rats were then further tested each month for five months for reductions in their turning behavior. At 5 to 6 months postgrafting, electrophysiological recordings were made of cells within the graft and within the host striatum. The rats were then examined immunohistochemically to evaluate graft survival and extent of reinnervation of the host tissue. The rats receiving mesencephalic dopaminergic grafts demonstrated a 79% reduction in their apomorphine-induced rotations. Electrophysiological recordings revealed spontaneously active dopaminergic neurons within the graft as well as host striatal cell firing rates consistent with those of dopamine-innervated cells. Furthermore, immunohistochemical studies confirmed graft survival and revealed marked fiber outgrowth from the graft into and throughout the striatum. Taken together these findings provide evidence that grafts of human fetal mesencephalic tissue are able to produce behavioral improvements in lesioned animals which are associated with the presence of dopaminergic neurons within the graft and are consistent with normal host striatal cell activity levels.     

尼古丁对帕金森病大鼠纹状体多巴胺及黑质自由基含量的影响

目的 :研究尼古丁对帕金森病大鼠的影响 ,探讨其对 PD的作用机制。方法 :通过 6 - OHDA脑立体定向注射术建立大鼠帕金森病模型。采用生化方法观察不同剂量尼古丁对帕金森病大鼠的作用 ,检测黑质自由基、抗氧化剂及多巴胺含量的变化。结果 :造模前及造模后皮下注射尼古丁的 PD大鼠 ,黑质自由基及抗自由基酶及多巴胺含量较PD组有明显改善 (P<0 .0 5 )。结论 :尼古丁可减轻 6 - OHDA对黑质 DA能神经元的损伤 ,对 PD大鼠具有保护作用     

Comparison of adrenal medullary, carotid body and PC12 cell grafts in 6-OHDA lesioned rats

The survival and functional properties of dispersed cell implants of catecholaminergic cells obtained from the peripheral nervous system of adult rats (adrenal medulla and carotid body glomus cells) and PC12 cells from a rat pheochromocytoma cell line were examined following transplantation into the striatum of the adult rat. The host animals, all with unilateral 6-hydroxydopamine (6-OHDA) nigrostriatal lesions, were divided into 5 groups: (1) PC12 cells transplanted into Cyclosporin-A treated hosts; (2) PC12 cell grafts into hosts without Cyclosporin-A treatment; (3) grafts of adrenal medullary cells; (4) grafts of glomus cells; and (5) vehicle controls. All animals were sacrificed one month after transplantation. Immunocytochemical staining for tyrosine hydroxylase, the rate-limiting enzyme for catecholamine synthesis, was used to identify and characterize the grafted cells. PC12 cells were detected in four of six Cyclosporin-A treated rats, and two of these grafts developed into tumors. However, only one of the six non-Cyclosporin-A treated hosts was found to have surviving PC12 cells, and none of these rats developed tumors. No significant differences in rotational behavior were seen in either of the PC12 cell recipient groups. Grafted cells could be identified in all of the adrenal medullary and glomus cell recipients. However, the number of surviving cells was quite limited, with not more than 100 tyrosine hydroxylase-positive grafted cells found in any one recipient. Tyrosine hydroxylase-positive fibers were present adjacent to the transplants in these latter graft recipients, but the fibers appeared to be of host origin rather than from the grafts.(ABSTRACT TRUNCATED AT 250 WORDS)     

外源性kynurenic acid对大鼠黑质多巴胺能神经元损伤的保护作用研究

目的观察评价预先应用谷氨酸(Glu)受体拮抗剂kynurenic acid(KYNA)对黑质多巴胺(DA)能神经元及神经传导纤维损伤的保护性作用. 方法雌性SD大鼠40只,随机分为4组,每组10只,应用江湾I型C立体定向仪,在单侧黑质致密部及中脑被盖腹侧部, A组注射生理盐水,B组注射KYNA,C组注射KYNA和6-羟基多巴胺(6-OHDA), KYNA先于6-OHDA 30 min, D组注射6-OHDA.注射药物3 d后,进行症状观察,4周后处死大鼠.切片HE染色观察黑质细胞的形态特点,冰冻切片免疫组化特殊染色观察酪氨酸羟化酶(TH)阳性细胞及TH阳性纤维着色情况.结果正常黑质细胞体形较大,富含黑色素颗粒,可见尼氏体.TH着色结果提示B组与A组之间无显著差异,P>0.05.实验组C与A、B、D组比较均有显著性差异,P<0.01.结论外源性Glu受体拮抗剂KYNA通过阻滞Glu受体一定时间阶段内能减轻6-OHDA诱导的黑质DA能神经元毒性损害.     

Fos蛋白和Jun蛋白在犬颅脑枪弹伤局部脑组织的表达

目的　研究犬颅脑枪弹伤后脑神经元早期快反应基因c fos和c jun表达产物Fos蛋白和Jun蛋白的变化规律。方法　 2 0只杂种犬 ,随机分为正常对照组、损伤组。以德国小口径步枪子弹致犬颅脑贯通伤 (PCI)模型为对象 ,采用免疫组化法检测脑组织伤后 30min、2h、6h弹道挫伤区、震荡区及脑干神经元中Fos和Jun蛋白的表达。结果　对照组脑皮质神经元中Fos和Jun蛋白弱表达 ,弹道挫伤区、震荡区及脑干神经元中Fos和Jun蛋白表达于伤后 30min开始增加 ,2h达到高峰 ,6h逐渐下降。且Fos和Jun蛋白表达在弹道震荡区较挫伤区更为明显 (P <0 .0 5 )。结论　Fos蛋白和Jun蛋白在弹道挫伤区、震荡区及脑干神经元均有表达 ,c jun在脑组织内表达的分布范围及变化趋势与c fos基本一致 ,其表达是对损伤刺激的早期反应 ,可能是由Leao播散性抑制引起 ,并与细胞内外信号转导和细胞凋亡有关。     

Dopaminergic cells of the carotid body: physiological significance and possible therapeutic applications in Parkinson's disease

Parkinson's disease is a neurodegenerative disorder characterized by the progressive loss of dopaminergic neurons in the substantia nigra projecting to the striatum. One therapeutic approach to this disease has been the intrastriatal transplantation of dopamine-secreting cells. We have investigated the suitability of glomus cells of the carotid body for dopamine-cell replacement in animal models of Parkinson's disease. Carotid body glomus cells are physiologic arterial oxygen sensors that release large amounts of dopamine in response to hypoxia. We have used hemi-Parkinsonian rats, induced by injection of 6-hydroxydopamine into the substantia nigra, and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treated monkeys with chronic Parkinsonism. In both cases we made transplants of carotid body cell aggregates into the putamen. Functional recovery of the grafted animals was observed after the surgery and was stable for several months. Although the study was more detailed in the rat, in the two animal models the amelioration of the motor deficits was paralleled by striatal dopaminergic reinnervation and survival of grafted glomus cells. Our results suggest that intrastriatal autotransplants of carotid body tissue could be a feasible technique to treat some cases of Parkinson's disease in humans.