树Qu黑质至上丘的γ—氨基丁酸能和多巴胺能阳性纤维投射

目的：研究树Qu黑质至上丘的γ-氨基丁酸（γ-aminobutyric acid,GABA)能和多巴胺（Depamine,POPA)能阳性纤维投射。方法：采用荧光金（Fluoro-Gold,FG)逆行追踪分别与GABA和DOPA免疫组化相结合技术。结果：在树Qu双侧黑质的致密部、网状部和外侧部均观察到FG逆行标记细胞;双侧黑质的网状部除向上丘发出GABA能纤维投射外,同侧黑质网状部还向上丘发出DOPA能纤维投射。此外,在同侧黑质的致密部,还观察到少量的向上丘投射的DOPA能神经元。结论：黑质向上丘的GABA和DOPA能阳性纤维投射为阐明黑质的生理功能提供形态学依据。     

树黑质至上丘的γ-氨基丁酸能和多巴胺能阳性纤维投射

目的研究树嗣黑质至上丘的γ氨基丁酸(γaminobutyricacid,GABA)能和多巴胺(Depamine,DOPA)能阳性纤维投射。方法采用荧光金(Fluo-Gold,FG)逆行追踪分别与GABA和DOPA免疫组化相结合技术。结果在树双侧黑质的致密部、网状部和外侧部均观察到FG逆行标记细胞;双侧黑质的网状部除向上丘发出GABA能纤维投射外,同侧黑质网状部还向上丘发出DOPA能纤维投射。此外,在同侧黑质的致密部,还观察到少量的向上丘投射的DOPA能神经元。结论黑质向上丘的GABA和DOPA能阳性纤维投射为阐明黑质的生理功能提供形态学依据。     

荧光金逆行标记观察正常大鼠视网膜神经节细胞及轴突

使用荧光金通过立体定位仪逆行标记对正常大鼠视网膜神经节细胞及其轴突进行观察研究。成年SD大鼠6只(12眼),体重250±20g,按照标记后1周,2周分为2组,每组3只(n=6眼)。将荧光金注射到大鼠的外侧膝状体和上丘,观察视网膜神经节细胞(RGCs)的数量和视网膜神经节细胞及其轴突的形态。结果显示:视网膜铺片的节细胞边界清楚,易于观察和计数。荧光金标记1周后,RGCs密度为2210±128个/mm2;标记后2周,RGCs密度为2164±117个/mm2。视网膜神经节细胞的轴突内荧光分布均匀,呈线性。结论是使用荧光金逆行标记能够可靠、有效地研究视网膜神经节细胞及其轴突。     

大鼠腰骼髓“内脏面”传出和上行投射神经元的定位分布——HRP与荧光金追踪法研究

用HRP与荧光金(FG)结合的示踪法,观察了大鼠腰骶髓“内脏面”副交感节前神经元和上行投射神经元的定位分布。发现FG注入一侧臂旁外侧核或Barrington核后,逆行标记的金色荧光细胞出现于双侧L_5～S_2的“内脏面”,细胞密集于后连合核和中间带外侧核(IML),此外,还出现于双侧的I层及外侧脊髓核(LSN)。HRP注射于一侧盆神经后,逆标细胞出现于术侧的L_6和S的IML,偶见于中介核(IC)。在IML内,HRP标记的副交感节前神经元位于其腹侧份,而FG标记的上行投射神经元主要位于背侧和背内侧部,亦可见少数FG标记细胞混杂在HRP标记细胞之间。本研究结合已有的研究对IML的命名、组成和功能以及LSN的组成进行了讨论。     

大鼠孤束核内儿茶酚胺能神经元接受面口部深层组织伤害性信息并向臂旁核投射的形态学研究

为了探讨孤束核(NTS)内儿茶酚胺能神经元是否与面口部深层组织的伤害性信息有关并向臂旁核投射,本研究运用荧光金(FG))逆行追踪,福尔马林刺激咬肌和免疫荧光技术相结合的三重标记方法,在荧光显微镜下观察了大鼠NTS内酪氨酸羟化酶(TH)阳性并表达FOS蛋白的神经元向臂旁核的投射。将2％FG注入一侧臂旁外侧核后,向同侧咬肌内注射2％福尔马林溶液,并行TH和FOS免疫荧光组织化学染色,荧光显微镜下在同侧NTS内的连合、内侧、中间内侧和腹侧亚核中可见重叠分布的FG、FOS、TH单标神经元以及FG／TH、FOS／TH、FOS／FG双标和FG／FOS／TH三标神经元。FG／TH和FOS／TH双标神经元分别占同侧NTS内TH阳性神经元总数的28.6％和34.8％;FOS／FG双标神经元占同侧FG逆标神经元总数的26.4％;FG／FOS／TH三标神经元分别占同侧TH阳性神经元和FG逆标神经元总数的23.7％和8.4％。本结果提示大鼠NTS中的部分儿茶酚胺能神经元接受面口部深层组织的伤害性信息并向臂旁外侧核传递。     

单色光对鸡视网膜节细胞密度和大小的影响

目的 研究单色光对鸡视网膜节细胞(RGCs)分布的影响.方法 采用二极管光(light-emitting diodes,LED)灯作为光源,将60只刚出壳的雄性从肉鸡分别饲养在红(660nm)、绿(560nm)、蓝(480nm)和白光(400～760nm)照下49d(n=15),光照强度15 lux,光照制度23h:1h(L:D).取两侧视网膜分别做Nissl染色和DiI标记RGCs,利用图像分析法观察视网膜面积、RCCs细胞密度与大小的变化.结果 蓝、绿光组视网膜面积、RGCs细胞总数显著高于红、白光组(10.35%和17.07%,P<0.05);绿光组RGCs平均细胞密度比其他光组高14.61%(P<0.05);绿光组视网膜中央区(CA)的RGCs密度最高,显著高于蓝光组28.91%(P<0.05),其CA/NP的比值比其他光组高29.71%(P<0.05);蓝光组CA的RGCs胞体面积最小,颞侧周边区(TP)和鼻侧周边区(NP)的胞体最大,其TP/CA的比值比其他光组高26.65%(P<0.05)且与其他光组相比差异显著(P<0.05).结论 蓝、绿光可使视网膜面积、RGCs细胞总数增加;从视网膜的中央区到周边部,绿光组的RGCs密度梯度下降幅度和蓝光组的RGCs大小梯度增大幅度最明显.     

猫二叠体旁核与上丘之间的定位联系——HRP法研究

对猫二叠体旁核与上丘之间的定位联系用逆行性和顺行性 HRP 追踪技术进行了研究。HRP 注射至吻端上丘后,对侧吻端二叠体旁核可见大量标记细胞,核之其余部位标记细胞较少,标记终末则主要分布在同侧二叠体旁核尾侧部,它们呈颗粒或念珠状,浓密地分布在核尾侧部的背腹侧范围内,尤以背侧区密度最高。相反,尾端上丘注射后,HRP 阳性细胞和标记终末主要见于同侧二叠体旁核尾侧部,但标记细胞与终末密度明显降低。我们还注意到注射区仅限于上丘浅层者,二叠体旁核内标记细胞较稀少,未发现标记终末;注射区位于上丘深层者,不仅在两侧二叠体旁核内可见较多标记细胞,而且在同侧二叠体旁核尾侧部还可见到一些标记终末。以上结果表明,二叠体旁核与上丘之间存在往返纤维联系,并有相应的吻—吻端,尾—尾端,以及吻—尾端定位投射关系,即吻端二叠体旁核主要投射至对侧吻端上丘;尾端二叠体旁核一方面投射到同侧上丘尾侧部,另一方面也接受同侧上丘、特别是吻侧上丘的强大输入,而发出纤维至二叠体旁核的母细胞体可能位于同侧上丘较深的板层。     

黄芪甲苷对成年大鼠视神经切断后视网膜节细胞存活的影响

目的:探讨黄芪甲苷(AST)在成年大鼠视神经切断后对视网膜节细胞(RGCs)存活的影响。方法:动物分为正常组、单纯切断视神经组、AST处理组和生理盐水对照组。用荧光金(FG)逆行示踪标记法及定量解剖学技术观察正常和经AST处理的SD大鼠于视神经切断后5、7、14 d的RGCs的密度。结果:正常组RGCs平均密度为(2 230±156)/mm~2。单纯视神经切断组RGCs平均密度与生理盐水对照组相比较,无显著性差异;AST处理组与单纯切断视神经组和生理盐水对照组相比较,在各个时间点上均存在显著性差异。结论:黄芪甲苷可提高成年大鼠视神经切断后视网膜节细胞短期存活。     

新生犊牛视网膜节细胞的形态分布

目的:研究比较新生犊牛视网膜节细胞(RGCs)的数量、大小和密度的形态学变化。方法:采用Nissl染色、荧光染料DiI逆行标记技术和计算机图像处理方法。结果:RGCs在视神经乳头下方形成一个沿鼻颞侧轴方向伸展的高密度区(P1,2608/mm2;P21,2174/mm2),即视条纹。由视条纹至周边部细胞密度递减,颞侧周边部最低(P1,mm2;P21,217/mm2);细胞大小则呈递增的变化,这种变化趋势在颞侧最明显。由P1到P21,RGCs总数和平均细胞密度均递减而细胞大小递增。结论:RGCs大小由视条纹至周边部递增而细胞密度递减,并且由P1到P21,RGCs总数和细胞大小递增而细胞密度递减。     

大鼠三叉神经节内含内吗啡肽2的神经元向延髓背角投射

目的 观察大鼠三叉神经节(TG)内的内吗啡肽2(EM2)阳性神经元向延髓背角(MDH)的投射情况.方法 荧光金(FG)追踪与EM2免疫荧光组织化学染色相结合的双标方法.结果 将FG注入MDH后,TG内可见大量FG标记的大、中、小型神经元;TG内也可见各种直径的EM2阳性神经元;TG内的许多FG标记神经元呈EM2阳性,FG/EM2双标神经元多为中、小型神经元.结论 TG内的EM2阳性神经元向MDH投射.     

Cyan fluorescent protein (CFP) expressing cells in the retina of Thy1-CFP transgenic mice before and after optic nerve injury

We investigated the specificity of cyan fluorescent protein (CFP) expression in retinal ganglion cells (RGCs) of the transgenic Thy1-CFP (B6.Cg-Tg(Thy1-CFP)23Jrs/J) mouse line, and the characteristics of these cells after optic nerve injury. RGCs of adult Thy1-CFP mice were retrogradely labeled with fluorochrome (2% fluorogold [FG]) from the superior colliculi (SC). Animals were sacrificed 7 days after RGC labeling. Retinas were fixed and whole-mounted. CFP and FG-positive cells were visualized and imaged separately. Cells positive for CFP, FG, or co-labeled were counted. In another group of animals, the left optic nerves were transected 7 days after FG labeling. They were sacrificed 7 or 21 days after transection. The retinas were whole-mounted and the characteristics of CFP-expressing cells examined. CFP-expressing cells were distributed evenly throughout the retinas of Thy1-CFP mice. The average densities of CFP and FG-positive cells in the retina were 2778 ± 216 and 3230 ± 157 cells/mm², respectively. 93.2 ± 1.6% of CFP-expressing cells were also labeled with FG. However, only 79.9 ± 2.5% of FG-labeled RGCs expressed CFP. The number of CFP-expressing cells decreased dramatically after transection. Cells with spindle shape, immunohistochemically identified as microglia, were seen in the retina with CFP expression at both 7 and 21 days after optic nerve transection. In retinas of Thy1-CFP mice, CFP is expressed by the large majority of RGCs, but not exclusively by RGCs. CFP is internalized by phagocytosing cells after injury to RGCs.     

A retrograde fluorescence double-labeling study of the cat's optic nerve cell which has a bifurcating axon.

Injection of the fluorescent tracers, Evans Blue (EB) and 4'-6-Diamidino-2-phenylindole dihydrochloride hydrate (DAPI) or Fluoro-Gold (FG) into the dorsal nucleus of the lateral geniculate body (dLGN) and the ipsilateral superior colliculus (SC) of adult cats demonstrated the existence of double-labeled optic nerve cells in the retina denoting that their axons bifurcate and project to both of these structures. These cells were seen in the temporal half and dorsal-dorsonasal and ventral-ventronasal octants of the ipsilateral retina and accounted for 11.5% of all the labeled cells. On the contralateral side, they were seen in the entire retina and accounted for 13.7% of all the labeled cells.     

成体金黄地鼠神经节细胞轴突在外周神经移植到视网膜后的再生

在成体金黄地鼠的视网膜上移植一段自体坐骨神经1～4个月后,视网膜神经节细胞纤维长入移植的坐骨神经中长达2 cm。具有再生纤维的神经节细胞分布于外周神经插入处与视网膜边缘之间的扇形或带状区域内。细胞数目与插入处的位置有关,接近视神经乳头处较远离视神经乳头处标记细胞数量多。移植后的视网膜标记神经元细胞体面积分布直方图表明:具有再生纤维的神经元胞体面积范围除包括正常大小的神经节细胞外,还包括相当多的胞体增大的神经元。用荧光染料核黄施于视束、真蓝施于移植的坐骨神经后的逆行荧光双标记法实验表明,再生的轴突起源于神经节细胞的损伤轴突,而不是完整神经节细胞轴突的侧芽。     

Types of parvalbumin-containing retinotectal ganglion cells in mouse

The calcium-binding protein parvalbumin (PV) occurs in the retinal ganglion cells (RGCs) of various vertebrate species. In the present study, we aimed to identify the types of PV-containing RGCs that project to the superior colliculus (SC) in the mouse. We injected retrograde tracer dextran into the mouse SC to label RGCs. PV-containing RGCs were first identified by immunocytochemistry and then neurons double-labeled with dextran and PV were iontophoretically injected with a lipophilic dye, DiI. Subsequently, confocal microscopy was used to characterize the morphologic classification of the PV-immunoreactive (IR) retinotectal ganglion cells on the basis of dendritic field size, branching pattern, and stratification within the inner plexiform layer. Among the 8 different types of PV-containing RGCs in the mouse retina, we found all 8 types of RGCs projecting to the SC. The RGCs were heterogeneous in morphology. The combined approach of using tracer injection and a single cell injection after immunocytochemistry on a particular protein will provide valuable data to further understand the functional features of the RGCs which constitute the retinotectal pathway.     

Retinal projection to the nucleus of the optic tract in the cat as revealed by retrograde transport of horseradish peroxidase

Retrograde transport of horseradish peroxidase injected iontophoretically into the nucleus of the optic tract of cats revealed that the direction-selective cells in this pretectal nucleus receive direct retinal projections from small retinal ganglion cells, the so-called gamma-cells. These cells from a horizontal band on the contralateral retina. Few labeled cells are found in the ipsilateral temporal retina. The input from the contralateral retina is 10 times more numerous than from the ipsilateral one. In both retinae the highest concentration of labeled cells is near the area centralis.     

Large retinal ganglion cells in the rat: their distribution and laterality of projection

Summary The distributions of the ipsilaterally and contralaterally projecting large ganglion cells in the retina of the rat were determined, using the retrograde transport of Horseradish peroxidase (HRP) following injections into one optic tract. Labelled large retinal ganglion cells occur throughout the contralateral retina and throughout the temporal crescent of the ipsilateral retina, but there is a noticeable decrease in their density in the contralateral retina's temporal crescent. This retinal region was identified in these same retinae by injecting a retrogradely transported flourescent tracer into the optic tract opposite that receiving the HRP. The density of large retinal ganglion cells increases in both the contralateral retina and the ipsilateral temporal crescent in the upper temporal periphery such that, together, these two populations of large cells combine to produce a peak density centred on the retinal representation of the visual field's vertical midline. This peak density of large retinal ganglion cells must therefore be further peripheral than the peak density for the total population of retinal ganglion cells, since all evidence indicates that the latter is positioned nasal to the vertical midline's representation. This was verified in one rat, in which the density distribution of the total population of retinal ganglion cells was determined and compared with the distribution of the large cell population. The results suggest that the rat possesses a specialized retinal focus of large ganglion cells for viewing the visual field directly in front of the animal.     

H89和wortmannin对霍乱毒素促进远端视神经损伤后视网膜节细胞再生的影响

目的：探讨H89和wortmannin对霍乱毒素(CTx)促进成年金黄地鼠远端视神经受损后视网膜节细胞(RGCs)再生的影响。方法：远端切断视神经并对接一段自体坐骨神经(AG)，玻璃体内注射CTx及H89、wortmannin。动物随机分为AG；AG CTx组；AG CWx H89组；AG CTx wortmannin组，4w后粒蓝逆行标记再生的RGCs，荧光显微镜下观察计数。结果：AG CTx组再生的视网膜节细胞平均数(43．2)明显高出AG组(2.6)，AG CTx H89组平均再生数为3．2，与AG组相近，明显低于AG CTx组。AG CTx W组平均再生数为9.6，明显高于AG，低于AG CTx组。结论：H89和wortmannin可部分抑制CTx对视神经远端切断后视网膜节细胞再生的促进作用。     

外伤性视神经损伤后视神经及视网膜形态的动态观察

目的:了解外伤性视神经损伤后的病理变化、溃变特点与时相间的关系。方法:参照Allen脊髓损伤法,造成视神经眶尖段间接600gcm力冲击、挤压伤。伤后对视神经和视网膜行形态学动态观察。结果:①伤后48h,视神经轻度肿胀和空泡反应;1周时损伤处视神经出现溃变,神经胶质细胞增生,视网膜神经节细胞(retinalganglioncells,RGCs)形态改变不明显;2周时神经纤维轴束间空泡样改变,局灶性坏死,RGCs核固缩和细胞数量减少。术后3月,视神经损伤部位直径缩小,形成胶质疤痕,RGCs数量明显减少,核固缩细胞增多。②RGCs数量于术后48h、1周、2周、1月和3月分别比正常对照组低3.35%、13.23%、19.74%、23.20%、29.28%。③视网膜细胞在48h内出现凋亡。结论:本实验模型可造成明确的视神经和视网膜损伤,神经元的损伤程度从节细胞、中间神经元、感光细胞的次序依次递减。视网膜和视神经损伤的严重程度与时间呈相关性。RGCs数量在48h至1周时下降速率最快。     

神经干细胞玻璃体内移植后的分化及对视网膜节细胞的影响

目的： 观察视神经(ON)微挤压断后玻璃体内移植神经干细胞（NSCs）的分化情况及其对视网膜节细胞(RGCs)轴突再生的促进作用。方法: 在成年大鼠球后1 mm处微挤压断ON，在玻璃体内注入Hoechst33342标记的NSCs 2×10⁴个，实验动物分对照组(MC组、MC+PBS组)、实验组(MC+NSCs组)，各组动物分别存活3、4、5周。用粒蓝逆行标记再生的RGCs，在荧光镜下观察视网膜平铺片再生RGCs的数量变化。另取实验组5只动物存活4周后取眼球切片观察NSCs分化情况。结果: 存活3、4 、5周，再生的RGCs 数目实验组与对照组有显著差异（P<0.01）。4周后移植的NSCs表达NF、CNP、GFAP；未见NSCs迁移至视网膜内。结论: 玻璃体内注入NSCs可显著促进ON微挤压断后RGCs轴突的再生，并在玻璃体内分化为神经元、星形胶质细胞和少突胶质样细胞。     

A GABAergic projection from the pretectum to the dorsal lateral geniculate nucleus in the cat.

To study the projection from the pretectum to the lateral geniculate nucleus, we placed wheat-germ agglutinin conjugated to horseradish peroxidase into the lateral geniculate nuclei of six cats, allowed this marker to be retrogradely transported by afferent axons to their parent somata in the pretectum, and revealed the label in these cells with stabilized tetramethylbenzidine histochemistry. In three cases we made large pressure injections that completely infiltrated the lateral geniculate nucleus and extended into neighboring thalamic nuclei; in the other three we made smaller iontophoretic injections largely confined to the A- and C-laminae of the lateral geniculate nucleus. In both types of injection we found labeled pretectal cells mainly in the nucleus of the optic tract but also found some cells labeled in the olivary pretectal nucleus and the posterior pretectal nucleus. After one of the larger injections we analysed both sides of the pretectum and found that 11% of the labeled cells were located contralaterally and were distributed in the same three nuclei. We analysed only the ipsilateral side in the remaining five cats. In those five experiments we also immunohistochemically stained the pretectal sections with an antibody directed against the neurotransmitter, GABA. Of the retrogradely labeled pretectal cells, 40% were also labeled for GABA, and those were similar in soma size (350 microns 2 in cross-sectional area) to those labeled only with the retrograde marker (331 microns 2). GABA-positive cells not labeled by retrograde transport were smaller (246 microns 2) than either of these other cells populations. These results indicate that at least 40% of the cells involved in the projection from the pretectum to the lateral geniculate nucleus are GABAergic. We suggest that this extrathalamic projection may serve to inhibit thalamic GABAergic cells. This, in turn, would disinhibit geniculate relay cells, thereby facilitating the geniculate relay of retinal information to cortex.