重组人促红细胞生成素预处理对黑质多巴胺能神经元凋亡的影响

目的研究重组人促红细胞生成素(rhEPO)对离体帕金森病模型中黑质多巴胺神经元凋亡的影响。方法以6-羟基多巴胺(6-OHDA)为毁损剂建立大鼠离体帕金森病(PD)模型。用6u/mlrhEPO预处理黑质多巴胺神经元,然后用免疫组化方法观察黑质中酪氨酸羟化酶(TH)免疫反应阳性细胞数和半胱天冬酶-3(Caspase-3)免疫反应阳性细胞数的变化,TUNEL法观察黑质中多巴胺神经元的凋亡情况。结果与6-OHDA组(44.2±5.0)相比,rhEPO预处理组TH免疫反应阳性细胞(63.8±6.2,P<0.01)增多;与6-OHDA组(22.3±2.8)相比,rhEPO预处理组多巴胺神经元中Caspase-3表达减少,Caspase-3免疫反应阳性细胞染色较淡,数量减少(13.7±1.8,P<0.01);与6-OHDA组(20.3±3.1)相比,rhEPO预处理组TUNEL阳性细胞染色较淡,数量减少(10.7±1.5,P<0.01)。结论rhEPO预处理可以减轻6-OHDA对离体帕金森病模型中多巴胺神经元的损伤,其机制可能与rhEPO抑制黑质多巴胺神经元凋亡有关。     

脑源性神经营养因子对帕金森病大鼠多巴胺能神经元的影响

目的观察脑源性神经营养因子对帕金森病(Parkinson’s disease,PD)大鼠模型黑质多巴胺能神经元的影响。方法选用Wistar种系大白鼠30只,体质量230~250g,随机分3组,通过左侧中脑黑质立体定向注射法,组1为生理盐水对照组(简称对照组)10只,注射相应量(5μL)的生理盐水;组2为注射6-OHDA制作帕金森病模型组(简称6-OHDA组)10只,注射6-OHDA,5μL(2μg/μL);组3为(6-OHDA+BDNF)组,在制成帕金森病模型后再向同侧中脑黑质注射BDNF 5μL(3μg/5μL),连续6d,1次/d。分别观察动物的旋转行为,免疫组化染色方法观察黑质酪氨酸羟化酶(tyrosine hydroxylase,TH)阳性神经元的数量,高效液相法测定纹状体部多巴胺(dopamine,DA)含量的变化。结果单侧黑质内注入6-OHDA制成帕金森病大鼠模型后,6-OHDA组与对照组比较,产生旋转行为,(6-OHDA+BDNF)组在观察旋转行为时,症状明显改善;镜下见TH阳性神经元主要见于对照组的黑质致密部,数量为(42.3±7.56)个/μm2,模型组黑质致密部TH阳性神经元数明显减少为(2.41±1.07)个/μm2,(6-OHDA+BDNF)组黑质致密部TH阳性神经元数为(15.36+3.04)个/μm2;纹状体部多巴胺含量:生理盐水组为(11.4±1.2)μg/g,6-OHDA组(3.6±0.5)μg/g,(6-OHDA+BDNF)组(5.5±0.6)μg/g。结论 BDNF能改善6-OHDA所致的帕金森病大鼠黑质多巴胺能神经元数目的减少;明显抑制6-OHDA引起的纹状体部多巴胺含量降低;并可抑制6-OHDA对黑质多巴胺能神经元的毒性作用。     

6-OHDA诱导大鼠多巴胺神经元选择性缺失的研究

目的 电压依赖性钙离子通道分布对6-羟基多巴胺（6-OHDA）诱导的SD大鼠多巴胺能神经元缺失的影响.方法 6-OHDA单侧脑内内侧前脑束（MFB）立体定位注射,术后10d观测行为学变化;并取脑固定,免疫组化酪氨酸羟化酶（TH）染色观察中脑黑质致密部（SNc）与腹侧背盖区（VTA）多巴胺能神经元的凋亡情况.并应用膜片钳全细胞记录技术,测量SNc与VTA多巴胺能神经元的电压依赖性钙离子通道的电流密度.结果 损伤侧的SNc区TH阳性细胞与对侧比较明显减少,而VTA区TH阳性细胞与对侧相比变化较小;全细胞记录电压膜片钳技术测量,发现SNc多巴胺能神经元钙通道电流密度与VTA相比明显较高.结论 该结果的发现,提示钙离子通道可能参与到帕金森氏病中脑多巴胺能神经元的选择性凋亡的机制.     

灵芝孢子粉对帕金森病模型鼠黑质酪氨酸羟化酶的影响

目的研究灵芝孢子对帕金森病(PD)模型鼠脑黑质酪氨酸羟化酶(TH)的影响,以探讨灵芝孢子对PD的脑保护作用。方法120只SD大鼠随机分为三组,PD组:立体定向注入6-羟多巴(6-OHDA),术后1周腹腔注入阿朴吗啡观察30min大鼠旋转的次数,连续至第四周每分钟大于6次者为成功的PD模型;灵芝孢子组:先用灵芝孢子粉灌胃3d,立体定向注入6-OHDA,继续灌胃4周,直至处死;正常对照组:立体定向注入脑黑质抗坏血酸生理盐水。处死后制作快速冰冻切片用免疫组化检测TH阳性细胞数,用原位杂交法检测THmRNA的阳性细胞数,用Westernblot检测TH的半定量变化,用高效液相色谱检测多巴胺水平的变化。结果免疫组化显示灵芝孢子组术侧鼠脑黑质TH阳性神经元数量为99·7±13·6,PD组为51·0±13·5,灵芝孢子组较PD组显著升高(P<0·05);原位杂交显示灵芝孢子组术侧鼠脑黑质THmRNA阳性神经元数量为180·3±24·3,PD组为72·7±15·0,灵芝孢子组较PD组显著升高(P<0·01);Westernblot检测显示TH蛋白灵芝孢子组较PD组显著增加;高效液相色谱检测术侧鼠脑黑质多巴胺(DA)水平灵芝孢子组为(0·7±0·3)ng/mg蛋白,PD组为(0·4±0·1)ng/mg蛋白,灵芝孢子组较PD组显著升高(P<0·05)。结论灵芝孢子能够提高TH的表达,并提高鼠脑黑质DA的水平,推测对6-OHDA诱导的PD可能有脑保护作用。     

双靶点注射6-OHDA建立帕金森病大鼠模型并提高成功率

目的建立大鼠帕金森病模型,观测其行为学、中脑黑质多巴胺能神经元及超微结构的变化。方法利用立体定向技术,注射6-OHDA至大鼠中脑黑质SNc和中脑腹侧被盖区VTA,于注射后2、4、6、8周观测阿朴吗啡诱导的大鼠旋转行为学变化;采用免疫组化染色检测TH的表达,了解中脑黑质多巴胺能阳性神经元变化;利用透射电镜了解黑质区超微结构的变化。结果所有大鼠进行阿朴吗啡诱导旋转行为测试,旋转圈数>7r/min,并且>210r/30min,为合格的PD大鼠模型。大鼠模型于第4、6和8周时,大鼠行为学变化较为恒定。第8周时,50只大鼠中出现32只大鼠大鼠旋转次数平均为11.5±1.2/分,造模成功率为64%。PD模型大鼠超微结构观察,黑质神经元数目明显减少,线粒体肿胀,粗面内质网囊性扩张、脱颗粒,髓鞘扩张。免疫组化检测,成功模型光镜下分别计数双侧黑质TH阳性神经元,损毁侧黑质TH阳性神经元占正常侧的3.0%,即毁损侧TH阳性神经元减少97.0%。结论利用立体定向技术,选择黑质和中脑腹侧被盖区等双靶点,可建立6-OHDA大鼠PD模型,具有明确病理变化,提高模型成功率。     

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。     

立体定向技术注射6-OHDA至内侧前脑束建立帕金森病大鼠模型

目的 建立大鼠帕金森病模型,观测其行为学和多巴胺能神经元的变化.方法 利用立体定向技术,注射6-OHDA至大鼠脑的内侧前脑束,于注射后2、4、6、8周观测阿朴吗啡诱导的大鼠旋转行为学变化;采用免疫组化染色检测TH的表达,了解中脑黑质多巴胺能阳性神经元变化.结果 所有大鼠分别于第2、4、6、8周的进行阿朴吗啡诱导旋转行为测试,67只大鼠中出现16只大鼠(23.8%)旋转圈数＞7r/min,并且＞210r/30min,为合格的PD大鼠模型.第8周时,大鼠旋转次数平均为10.48±1.91/分.免疫组化检测,成功模型光镜下分别计数双侧黑质TH阳性神经元,损毁侧黑质TH阳性神经元占正常侧的3.8%,即毁损侧TH阳性神经元减少96.2%.结论 利用立体定向技术,选择内侧前脑束为靶点,可建立6-OHDA大鼠PD模型.     

灵芝孢子粉对帕金森病黑质神经细胞caspase-3影响的实验研究

目的：研究灵芝孢子对帕金森病（PD）大鼠模型黑质神经细胞caspase-3的影响。方法：SD大鼠随机分为3组，PD组：经立体定向向黑质部注入6-羟多巴（6-OHDA）；灵芝孢子组：先用灵芝孢子粉灌胃3d，立体定向注入6-OHDA，继续灌胃4周；正常对照组：立体定向注入抗坏血酸生理盐水。实验大鼠4周处死后用免疫组化、原位杂交检测caspase-3及其mRNA的阳性细胞数，Western blot检测caspase-3的半定量。结果：灵芝孢子组术侧黑质caspase-3及其mRNA阳性神经元数量较PD组明显降低，Western blot显示caspase-3蛋白较PD组显著降低。结论：灵芝孢子能够降低caspase-3的表达，对PD大鼠有脑保护作用。     

镁对帕金森病大鼠黑质多巴胺神经元的影响

目的观察镁对帕金森病(PD)大鼠黑质多巴胺神经元影响及其作用机制。方法应用6-羟基多巴胺(6-OHDA)制备偏侧PD大鼠模型后分为硫酸镁组、美多巴组、混合组(硫酸镁+美多巴)和对照组(生理盐水),并给予相应药物灌胃治疗28d。观察治疗后各组大鼠旋转行为的变化;免疫组化法检测黑质酪氨酸羟化酶(TH)阳性神经元数量;生化法测定损毁侧纹状体超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量;逆转录聚合酶链反应检测损毁侧黑质caspase-3 mRNA表达;Western Blot法检测核因子(NF)-кBP65水平。结果治疗后仅混合组出现较稳定的向对侧的旋转行为;TH阳性神经元数混合组较其他各组明显增加(均P<0.05);与对照组和美多巴组比较,硫酸镁组和混合组SOD、GSH-Px活性显著增高,MDA、caspase-3 mRNA、NF-кBP65水平显著降低(均P<0.05);硫酸镁组与混合组间差异无统计学意义。结论镁及美多巴联合治疗可提高PD模型脑内多巴胺神经元存活、降低氧化应激损伤、减少神经元凋亡,改善PD大鼠症状。     

人胎盘底蜕膜间充质干细胞抗炎特性对帕金森病模型大鼠的神经保护作用

目的 研究人胎盘底蜕膜间充质干细胞(hPDB-MSCs)抗炎特性对帕金森病(PD)模型大鼠多巴胺能神经元的影响. 方法 体外培养hPDB-MSCs,6-羟基多巴(6-OHDA)制备大鼠PD模型并按照随机数字表法分为模型组与移植组,每组32只.hPDB-MSCs尾静脉移植观察各组大鼠行为学改变.免疫组化检测移植后3d、1周、2周及4周各组大鼠损伤侧黑质酪氨酸羟化酶(TH)、离子钙接头蛋白(Ibal)表达.实时荧光定量PCR检测各时间点各组大鼠损伤侧黑质抗炎因子人白细胞介素-10 (hIL-10)、人转化生长因子-β(hTGF-β)及肿瘤坏死因子-α(TNF-α)表达. 结果 hPDB-MSCs移植后1周、2周、4周,移植组大鼠阿朴吗啡诱导的平均旋转圈数明显低于模型组,差异有统计学意义(P＜0.05).免疫组化结果显示移植组大鼠损伤侧黑质部位TH阳性细胞数较模型组明显增加,1周、2周、4周时差异有统计学意义(P＜0.05).移植组大鼠损伤侧黑质部位Ibal阳性细胞则明显减少,4周时最为显著.mRNA水平,移植组大鼠hIL-10及hTGF-β表达均较模型组增加,而TNF-α表达量则逐渐降低. 结论 hPDB-MSCs尾静脉移植后能够通过抗炎机制抑制PD模型大鼠多巴胺能神经元丧失,改善PD模型大鼠症状.     

Development of the projection from the nucleus of the brachium of the inferior colliculus to the superior colliculus in the ferret

Neurons in the deeper layers of the superior colliculus (SC) have spatially tuned receptive fields that are arranged to form a map of auditory space. The spatial tuning of these neurons emerges gradually in an experience-dependent manner after the onset of hearing, but the relative contributions of peripheral and central factors in this process of maturation are unknown. We have studied the postnatal development of the projection to the ferret SC from the nucleus of the brachium of the inferior colliculus (nBIC), its main source of auditory input, to determine whether the emergence of auditory map topography can be attributed to anatomical rewiring of this projection. The pattern of retrograde labeling produced by injections of fluorescent microspheres in the SC on postnatal day (P) 0 and just after the age of hearing onset (P29), showed that the nBIC-SC projection is topographically organized in the rostrocaudal axis, along which sound azimuth is represented, from birth. Injections of biotinylated dextran amine-fluorescein into the nBIC at different ages (P30, 60, and 90) labeled axons with numerous terminals and en passant boutons throughout the deeper layers of the SC. This labeling covered the entire mediolateral extent of the SC, but, in keeping with the pattern of retrograde labeling following microsphere injections in the SC, was more restricted rostrocaudally. No systematic changes were observed with age. The stability of the nBIC-SC projection over this period suggests that developmental changes in auditory spatial tuning involve other processes, rather than a gross refinement of the projection from the nBIC.     

Mechanisms of the suppression of the nociceptive reflex of the opening of the mouth during stimulation of the structures of the limbic brain

The comparative effectiveness of the inhibitory influence of tetanic stimulation of hypothalamus, amygdala and limbic cortex on EMG-response of m. digastricus evoked by electrical stimulation of tooth pulp nociceptive afferents was studied in cats anesthetized with a mixture of chloralose and nembutal. It was found that inhibition of the EMG-component of the jaw-opening reflex is most pronounced in case of stimulation of medial and lateral region of the hypothalamus, the inhibitory effect of central and medial nuclei of the amygdala is less pronounced and the effect of the limbic cortex is the weakest. It was shown that the mechanism of the antinociceptive effect of tetanic stimulation of the hypothalamus is not related to the concomitant increase of the blood pressure. After stabilization of the blood pressure the suppressive effect of the hypothalamus remains without changes, that points out to a direct, primary, not baro-afferent mechanism of the inhibition of the activity of nociceptive neurons of the trigeminal sensory nuclei. Noradrenaline, injected intravenously, induced a large increase of the blood pressure accompanied by a pronounced inhibition of the pain reflex. Angiotensin causes the same degree of blood pressure elevation without changes in the amplitude of the EMG-response of the pain reflex. Hypothalamic and noradrenergic mechanisms for control of pain sensitivity are discussed.     

The organization of the connections between the cortex and the claustrum in the monkey

The distribution of labelled cells and of extracellular granules in the claustrum has been studied after injections of horseradish peroxidase in several areas of the neocortex. The frontal and parietal lobes are related to the anterior and posterior halves respectively of the claustrum, and the occipital and temporal cortex to the posterior and inferior margins. Parts of the claustrum related to areas of the cortex in the frontal lobe overlap considerably in the antero-posterior dimension with parts related to widely separated but interconnected areas of the parieto-temporal cortex. Areas of cortex within one lobe which are interconnected are related to parts of the claustrum which overlap in the dorsoventral dimension.     

Experimental study of the projections of the nucleus of the tractus solitarius and the area postrema in the cat

Projections from the area postrema and adjacent parts of the medial solitary nucleus are demonstrated with the Nauta method following lesions limited exclusively to these structures. Experiments are controlled with lesions involving adjacent bulbar regions, cerebellum, and spinal cord. Ascending pathways in the dorsal and lateral columns of the spinal cord project ipsilaterally to the area postrema and bilaterally to a para-alar nucleus in the ventral periphery of the nucleus gracilis. Neurons in the area postrema project mainly inspilaterally to the dorsal and medial regions of the medial solitary nucleus. Neurons in the posterior half of the medical solitary nucleus project ipsilaterally to the lateral solitary nucleus, dorsal vagal nucleus, ambigus, retrofacial nucleus, and dorsal and lateral bulbar reticular formation. Projections to nuclei intercalatus and prepositus hypoglossi, bilaterally, and to the ipsilateral dorsal tegmental nucleus by way of the dorsal longitudinal fasciculus are also shown. No direct projections to the diencephalon are demonstrated. Control lesions in the dorsal column nuclei reveal projections to the contralateral inferior olive and thalamic reticular and ventrobasal nuclei, but not to the projection sites of the solitary nucleus. Evidence is given to support the hypothesis that ascening visceral pathways are interruped in the bulbar reticular formation and dorsal tegmental nucleus before reaching the diencephalon. Correlations are suggested with functional aspects of the central autonomic and reticular activating systems.