家兔脊髓固有束的起始细胞和终支的分布——HRP法研究

将HRP分别注入家兔脊髓的C_(6,7)、L_(5,6)和T_(5～7),C注射者观察L_5和T_5,L注射者观察C_5和T_5,T注射者观察C_5和L_5的标记细胞和顺行标记终支。标记细胞大量且恒定地存在于Ⅶ(包括胸髓的侧角)、Ⅷ层;其次为Ⅴ层和Ⅹ区;Ⅰ层的标记细胞多见于C、L,于T基本未见;Ⅳ、Ⅵ层的标记细胞不恒定且数量少;Ⅸ层在T可见少量,于L仅见个别,在C则未见到;Ⅱ、Ⅲ层于所有各例均未见到标记细胞。标记终支分布范围较广,几乎见于灰质各层。以Ⅹ区、Ⅶ层(包括胸髓的侧角)和Ⅷ层较为密集;L注射例在C_5腹角的腹外侧可见到明显的丛状终支,而于C注射例在L_5则未见到此特殊结构。还见到一些标记终支重叠在标记细胞上或紧挨其附近,也见到标记终支存在于未标记的运动神经元旁。根据形态学结果提出以下几点看法:1.胸髓Ⅶ区外侧分(侧角)出现标记细胞和终支,提示脊髓节段间联系不仅与躯体运动有关,而且也和内脏活动有关。2.Ⅹ区标记细胞恒定,标记终支也较密集,提示该区在脊髓节段间的联系方面起着一定的作用。3.腰膨大发出长的上升束,直接到达颈膨大腹角的腹外侧份,起着对运动神经元直接调节的作用。4.标记细胞旁有标记终支说明脊髓节段间有着反馈联系。     

家兔小脑中央核向脊髓直接投射的研究

本实验将WGA-HRP分別注入家兔脊髓一侧的颈、胸、腰等不同节段,逆行追踪小脑中央各核向脊髓的直接投射。结果表明,小脑中央核的标记神经元恒定地见于颈段(C_1～C_4)注入例动物,而未见于下颈段(C_6～C_8)和胸腰段注入例动物。标记神经元仅出现于注入侧对侧的小脑顶核及间位核的尾侧部。研究结果提示,家兔小脑顶核及间位核的尾侧部,有向颈髓的直接越边投射。本结果为进一步探讨小脑对躯体运动的调节功能提供形态学基础。     

鸡脊髓小脑束起始神经元的节段性分布

目的:探索鸡脊髓小脑束起始细胞在脊髓的分布规律.方法:采用压力注射法将辣根过氧化物酶(HRP)引入鸡小脑Ⅴ、Ⅵ、Ⅶ、Ⅷ、Ⅸ诸叶,逆行追踪脊髓小脑束起始神经元的分布.结果:(1)鸡脊髓小脑束起始神经元分布于Clarke氏柱、腹角灰质、腹角内缘、腹角外缘、外侧索和腹侧索,并在禽类所特有的边缘柱发现起始神经元.(2)标记神经元在腰骶膨大部出现最多.(3)分别注射Ⅵ、Ⅶ叶在脊髓均有标记细胞出现,而注射Ⅴ叶、Ⅷ或Ⅸ叶在脊髓没有出现标记细胞.结论:鸡的脊髓小脑束主要起始于腰骶段脊髓,主要投射向小脑的Ⅵ、Ⅶ叶.     

家兔大脑、小脑和顶盖向脊髓直接投射的研究

将辣根过氧化物酶(HRP)分别注入家兔脊髓单侧的颈、胸和腰等不同节段,逆行追踪大脑、小脑和顶盖向脊髓的直接投射。结果表明,大脑皮质的HRP标记神经元仅见于C_(2-7)注入例动物;小脑中央核的标记神经元仅见于C_(2-4)注入例动物;顶盖上丘的标记神经元仅见于C_(2、3)注入例动物;而均未见于胸腰段注入例动物。标记神经元主要分布于注入侧的对侧。本研究确信,由大脑皮质发出的皮质脊髓束投射到脊髓C_(1-7)节段;由小脑中央核发出的小脑脊髓束投射到脊髓C_(1-4)节段,由顶盖发出的顶盖脊髓束投射到脊髓C_(1-3)节段。     

猫降结肠传出和传入神经元的节段性分布—HRP法研究

本文用HRP法研究了猫降结肠的传出和传入神经元节段性分布,结果表明:1.猫降结肠的副交感中枢位于双侧骶髓1—3节段,左侧占优势。标记细胞主要位于网状核,其次为中间带外侧核,细胞均为中、小型。2.在双侧腰髓1—4节段的中间带外侧核见到许多标记细胞。3.降结肠感觉神经纤维来自双侧T_(13)—L_5和L_7—Co_1脊神经节,其细胞形态多为圆形、椭圆形,以中,小型细胞为主。4.感觉神经元的中枢突经Lissauer束进入骶髓1—3节段,围绕后角形成较粗大的外侧束和较细的内侧束。外侧束到达脊髓灰质Ⅴ、Ⅶ层和灰质后连合,内侧束到达后角灰质第Ⅱ、Ⅲ层。     

运用辣根过氧化物酶和乙酰胆碱酯酶双标记法对家兔腰、骶、尾髓脊髓小脑束乙酰胆碱酯酶阳性神经元的研究

本研究采用10只家兔进行腰、骶、尾髓的脊髓小脑束乙酰胆碱酯酶阳性神经元定位研究。其中8只在小脑内注射HRP后,按Mesulam组化法追踪腰、骶、尾髓各节段的HRP-AChE双标及HRP单标神经元;作为对照,2只家兔同样节段的脊髓切片则单纯显示神经元的AChE活性。实验结果表明,家兔腰、骶、尾髓的各群脊髓小脑束神经元中,大多数细胞均为乙酰胆碱酯酶阳性神经元,但它们所含AChE的量可能有所不同。各群细胞中乙酰胆碱酯酶阳性神经元所占数量的多少可能与脊髓小脑束神经元的不同功能有关。     

大白鼠下行脊髓固有束的起始细胞和背外侧索核在脊髓内的联系

用尖端直径约120μm的微玻管,向大白鼠右侧胸髓中下部(T_7～T_(11))注入HRP水溶液,观察大白鼠下行脊髓固有束的起始细胞的分布和背外侧索核在脊髓内的联系。下行脊髓固有束起始细胞见于注射部头侧脊髓的双侧。7只实验动物中,注射部同侧有31000个标记细胞,对侧有31663个。标记细胞分布的高峰节段,右侧为T_3～T_5,占同侧标记细胞的38.17％;左侧为T_1～T_5,占49.78％。横切面上按Rexed细胞构筑分层,标记细胞见于脊髓双侧Ⅰ～Ⅹ层。以Ⅶ层最多,其次为Ⅷ层和Ⅳ层。该结果说明,大白鼠下行脊髓固有束主要起始于Ⅶ、Ⅷ和Ⅳ层,其他各层也参与脊髓节段间的联系。背外侧索核有到下部脊髓的下行投射。     

大鼠小脑核到脊髓的投射——HRP法研究

向23只大鼠的颈、胸、腰、骶各段脊髓的一侧灰质内注射30％HRP(Sigma Ⅵ)水溶液0.3～2.0μl,TMB反应,观察了小脑核中标记细胞的分布。小脑核到脊髓的投射细胞主要位于小脑顶核的中部,对侧较多。标记细胞分布于顶核各部,但以腹外侧及内侧部较为密集。在顶核和间位核之间的部位(有小脑皮质前庭纤维经过)以及间位核后部内侧亦有较多标记细胞。两侧的齿状核中有少量标记细胞。小脑核细胞主要投射到颈髓上部(C_(3～4)),少量可达颈髓下部(C_(5～8))。胸髓以下未见有投射纤维。     

鸡卵巢的传出和传入神经成份在脊髓内的分布

将霍乱毒素——辣根过氧化物酶(CB—HRP)注入鸡卵巢内,通过逆行及跨神经节追踪证实:1.被标记的初级传入神经元中枢突在双侧胸腰段脊髓(T_1—L_3)内出现标记终末。横断面观,其纤维由背外侧束(LT)进入灰质,后分为外侧束(LCP)和内侧束(MCP),主要止于灰质的Ⅰ、Ⅱ层,少量LCP进入Terni氏柱。2.在T_3—L_2髓节出现标记细胞,高峰位于T_6—T_7,主要位于Terni柱,弥散于脊髓灰质的中间带内侧核,中介核,网状核和中央管腹侧区,说明胸腰髓内含支配卵巢的长轴突型交感性节前神经元。     

家兔副神经外支及其分支的起始核

实验用真成年家兔15只。(1)HRP注入副神经外文,标记细胞出现在注射侧延髓锥体交叉下端和脊髓C_(1-5)节段,88.9%标记细胞分布在C_(1-4)。标记细胞成群或散在地分布在延髓锥体交叉下端中央管的前外、颈髓前角和中间带的各亚核。标记细胞的最大径在30.9-123.5μm之间,41μm以上的占88.8%。在注射侧的C_1、2、3、脊神经节、迷走神经下节和交感神经颈上节观察到标记细胞。(2)HRP注入斜方肌神经,标记细胞分布在同侧脊髓C_(1-8)节段,标记细胞分布在前角的大多数亚核。(3)在胸锁乳突肌神经近侧断端涂HRP结晶,标记细胞出现在同侧延髓锥体交叉下端和脊髓C_(1-3)节段,标记细胞分布在前角的多数亚核。斜方肌神经和胸锁乳突肌神经起始核在脊髓的位置有较多的重叠。     

Routes of entry into the cerebellum of spinocerebellar axons from the lower part of the spinal cord

Summary Among the newly discovered spinocerebellar cell groups, those at lumbar and more caudal levels of the cat's spinal cord were studied with regard to which of the two cerebellar peduncles, the restiform body or the superior cerebellar peduncle, is used by their axons. Bilateral injections with horseradish peroxidase were made into either of the anterior lobe or the posterior cerebellar termination area for spinocerebellar fibers, following unilateral transections of either the superior cerebellar peduncle or the restiform body, combined with low contralateral transections of the lateral and ventral funiculi. Following transection of the superior cerebellar peduncle, labeled neurons were found ipsilateral to the transection in the column of Clarke and in laminae IV–VI at L 3–L 7. Contralaterally, labeled neurons were found in the ventromedial nucleus and lamina VIII of the ventral horn in the sacro-coccygeal segments and in the medial part of lamina VII at L 6 and more caudal levels. All these neurons were regarded as sending their axons through the restiform body. Following transection of the restiform body, labeled neurons were found in the following areas contralateral to the transection: the dorsolateral nucleus of the L 3–L 6 segments, the lateral part of lamina VII at L 3–L 5/6, the medial part of lamina VII in L 6 and more caudal segments, and the ventrolateral nucleus of L 4–L 5. Ipsilaterally, labeled neurons were found in lamina VIII at L 4–L 6. All these neurons were regarded as sending their axons through the superior cerebellar peduncle. In addition to new information about the peduncular routes of spinocerebellar neurons, the study has given confirming evidence as to the crossing conditions for different spinocerebellar cell groups. The findings should be useful in future studies on the organization of the spinocerebellar systems.Abbreviations BC brachium conjunctivum - BP brachium pontis - C cuneate nucleus - CC column of Clarke - DL dorsolateral nucleus - DSCT dorsal spinocerebellar tract - G gracile nucleus - lam lamina - lat lateral - LRN lateral reticular nucleus - LVN lateral vestibular nucleus - med medial - N.d. nucleus dentatus - N.f. nucleus fastigii - N.i. nucleus interpositus - p pyramidal tract - p. ant. pars anterior (of the paramedian lobule) - p. copul. pars copularis (of the paramedian lobule) - pfl. d dorsal paraflocculus - pmd paramedian lobule - p. post. pars posterior (of the paramedian lobule) - RB restiform body - SCP superior cerebellar peduncle - SVN spinal vestibular nucleus - VL ventrolateral nucleus - VM ventromedial nucleus - VSCT ventral spinocerebellar tract - I-X (on cerebellar diagrams) cerebellar lobules according to Larsell (1953) - IV–IX (on spinal cord diagrams), laminae according to Rexed (1954) - V (on brainstem diagrams) trigeminal nucleus - VI (on brainstem diagram) abducens nucleus - XII (on brainstem diagrams) hypoglossal nucleus On leave from Capital Institute of Medicine, Beijing, The People's Republic of China     

Collateral projections of neurons from the lower part of the spinal cord to anterior and posterior cerebellar termination areas

Summary The collateral projections of spinocerebellar neurons located in the L 2 to Ca 1 spinal segments in the cat were investigated by retrograde fluorescent double labeling technique. Rhodamine labeled latex microspheres (Rm) and Fast Blue (FB) were used for injections into the cerebellum in 8 cats. Two additional cats, with injections of Fluoro-Gold (FG) combined with Rm were excluded because lipofuchsin autofluorescence obscured the labeling. After injections with one tracer unilaterally in the paramedian lobule and another tracer bilaterally in the anterior lobe, double labeled neurons were found on the side of the paramedian lobule injection in the column of Clarke at L 2–L 4, laminae IV–VI at L 2–L 5 and the dorsolateral nucleus at L 2–L 6. After bilateral injections of one tracer in lobule VIII B and another in the anterior lobe, double labeled neurons were found bilaterally in the column of Clarke at L 2–L 4, laminae IV–VI at L 2–L 5, the medial part of lamina VII at L 6–L 7 and in certain cell groups at sacro-coccygeal levels. Neurons in the lateral part of lamina VII at L 3–L 5 and the ventrolateral nucleus of L 4–L 5 were labeled exclusively from injections in the anterior lobe. The findings indicate that spinocerebellar neurons at lumbar and more caudal levels of the cat spinal cord have different projection patterns in the cerebellum. A certain number of neurons which project to the anterior lobe have divergent axon collaterals supplying also the posterior vermis and/or the paramedian lobule. Other neurons project to the anterior or to the posterior lobe only.Abbreviations CC column of Clarke - DL dorsolateral nucleus - FB Fast Blue - lam. lamina - lat. lateral - med. medial - N. f. fastigial nucleus - p. copul. pars copularis (paramedian lobule) - pfl.d. dorsal paraflocculus - pmd paramedian lobule - p.post pars posterior (paramedian lobule) - pyr. pyramis - Rm Rhodamine labeled latex microspheres - VL ventrolateral nucleus - I–IX (on cerebellar diagrams) cerebellar lobules, according to Larsell (1953) - A, B (following Roman numeral VIII) sublobules VIII A and VIII B - IV–IX (on spinal cord diagrams) laminae according to Rexed (1954) On leave from Capital Institute of Medicine, Beijing, The People's Republic of China     

胎儿脊髓节段与脊柱位置关系的研究

目的 为研究个体发育年龄解剖学提供资料.方法 从胎儿背侧打开椎管,暴露脊髓,观察50例胎儿的脊髓节段与脊柱的位置关系.结果 各被观察脊髓节段下界的平均位置是:第4颈节平对第3颈椎(C_3);第8颈节平对第6～7颈椎间盘;第4胸节平对第3胸椎(T_3);第8胸节平对第7胸椎;第12胸节于对第10胸椎;第5腰节平对第12胸椎至第1腰椎间盘;脊髓末端在第2腰椎水平.结论 从胎儿到成人,脊髓下端的位置随着年龄的增长而逐渐上升.     

Dorsal border periaqueductal gray neurons project to the area directly adjacent to the central canal ependyma of the C4-T8 spinal cord in the cat

In a previous study horseradish peroxidase (HRP) injections in the upper thoracic and cervical spinal cord revealed some faintly labeled small neurons at the dorsal border of the periaqueductal gray (PAG). The present light microscopic and electronmicroscopic tracing study describes the precise location of these dorsal border PAG-spinal neurons and their terminal organization. Wheat germ agglutinin-conjugated HRP (WGA-HRP) injections into cervical and upper thoracic spinal segments resulted in several hundreds of small retrogradely labeled neurons at the dorsal border of the ipsilateral caudal PAG. These neurons were not found after injections in more caudal segments. WGA-HRP injections in the dorsal border PAG region surprisingly resulted in anterogradely labeled fibers terminating in the area dorsally and laterally adjoining the central canal ependyma of the C4-T8 spinal cord. No anterogradely labeled fibers were found more caudal in the spinal cord. The labeled fibers found in the upper cervical cord were not located in the area immediately adjoining the ependymal layer of the central canal, but in the lateral part of laminae VI, VII and VIII and in area X bilaterally. Electronmicroscopic results of one case show that the dorsal border PAG-spinal neurons terminate in the neuropil of the subependymal area and in the vicinity of the basal membranes of capillaries located laterally to the central canal. The terminal profiles contain electron-lucent and densecored vesicles, suggesting a heterogeneity of possible transmitters. A striking observation was the lack of synaptic contacts, suggesting nonsynaptic release from the profiles. The function of the dorsal border PAG-spinal projection is unknown, but considering the termination pattern of the dorsal border PAG neurons on the capillaries the intriguing similarity between this projection system and the hypothalamohypophysial system is discussed.     

大鼠脊髓神经肽Y、神经降压肽免疫反应神经元向结合臂旁核的投射

用HRP逆行束路追踪法结合免疫细胞化学双标记技术,研究了大鼠颈、胸、腰、骶各段脊髓神经肽Y(NPY)、神经降压肽(NT)免疫反应神经元向结合臂旁核的投射。HRP逆行标记细胞分布于两侧脊髓灰质第Ⅰ、Ⅱ、Ⅳ、Ⅴ、Ⅶ层、中央管背侧灰质连合及外侧颈核、外侧脊髓核中,以对侧为主。NPY免疫反应阳性神经元分布于两侧后角第Ⅰ层、第Ⅱ层浅部、外侧颈核、外侧脊髓核及骶髓后连合核中。NT免疫阳性神经元分布于两侧后角第Ⅰ层及第Ⅱ层中。在后角第Ⅰ层、外侧颈核和外侧脊髓核中,可观察到部分NPY-HRP双标记神经元;在后角第Ⅰ层可观察到部分NT-HRP双标记神经元。本研究结果提示,NPY和NT神经元可能参与脊髓-结合臂旁核的痛觉传递。     

猫肾上腺交感神经的来源

本文用HRP逆行标记法对13只猫的肾上腺交感神经元进行了定位研究,结果如下:1.交感神经节前神经元见于同侧脊髓T_2-L_1节段。其中T_7-T_(10)占61.1%。标记细胞大多数(97.4%)位于中间外侧核本部(ILP)。细胞形态,在横面上多呈梭形和卵圆形;在纵断面上,呈梭形.2.标记细胞见于同侧交感干神经节T_4-L_1节段。其中T_8-T_(13)占85.5%。细胞形态以卵圆形、梭形居多。标记细胞在神经节内散在分布。3.腹腔节标记细胞位于同侧半,细胞多为圆形和卵圆形。     

Spinocerebellar neurons and propriospinal neurons in the cervical spinal cord: a fluorescent double-labeling study in the rat and the cat

Summary In the cervical spinal cord of the rat and the cat, the distributions of spinocerebellar and of descending propriospinal neurons were investigated using the retrograde fluorescent double-labeling technique. Moreover, a search was made for the presence of neurons with both ascending spinocerebellar and descending propriospinal axoncollaterals. Diamidino Yellow Dihydrochloride (DY) was injected at T2, while True Blue (TB) (in rats) or Fast Blue (FB) (in cats) was injected in the cerebellum. The distributions of labeled neurons were very similar in the rat and the cat. DY-labeled propriospinal neurons, projecting to T2 or below, were most numerous in lamina I and laminae IV to VIII. In the rat, such neurons were also present in the lateral spinal nucleus (LSN). TB- or FB-labeled spinocerebellar neurons were concentrated in the central cervical nucleus (CCN) at C1-C4, in the central part of lamina VII at C5-T1, in the medial part of lamina VI and the adjoining dorsomedial part of lamina VII at C2/C3-T1, and in Clarke's column. They were also found in lamina V at C1 and C7-T1, and in lamina VIII at all levels. In both species only very few DYTB/FB double-labeled neurons, representing neurons with branching axons, were observed; in C1-T1, only about 0,5% of all TB/FB-labeled Spinocerebellar neurons and about 0,05% of all DY-labeled descending propriospinal neurons were double-labeled. The double-labeled neurons were all located centrally in lamina VII at C5-T1, but even in that area they constituted not more than 1,5% (rat) and 4% (cat) of the labeled spinocerebellar neurons. These findings indicate that, in the cervical cord of the rat and the cat, descending propriospinal neurons and spinocerebellar neurons are to a large extent separate populations.     

Retrograde HRP study of neurons in the cervical enlargement projecting to the cerebellum in the cat

Summary After cerebellar HRP injections in kittens labeled neurons were found in laminae V–VIII in the cervical enlargement. Most of the labeled neurons were localized in two groups, one in laminae V–VI, the other centrally in lamina VII. Labeled neurons were also observed in the medial part of lamina VII of C5 and T1 and a few in lamina VIII. Neurons in the cervical enlargement seem to terminate largely in cerebellar lobules IV–V of the anterior lobe. Some neurons in laminae V–VI terminated in the ipsilateral paramedian lobule. Neurons in laminae V–VI and central lamina VII of C5–T1 had uncrossed axons. Neurons in medial lamina VII of C5, in lamina VIII and neighbouring parts of lamina VII of C6–T1 had crossed axons. The ramifications of proximal dendrites and axons of the labeled neurons are described using the tetramethylbenzidine (TMB) method for HRP histochemistry. The neurons in the various laminae differed in their characteristic morphology. In conclusion, the findings of Matsushita et al. (1979) concerning the localization and axonal course of cerebellar projecting neurons in the cervical enlargement are confirmed. In addition new data concerning the morphology of the labeled neurons are presented.