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71.
72.
Victoria Chan-Palay 《Anatomy and embryology》1973,142(2):149-186
Summary Axon terminals in the neuropil of the lateral nucleus can be divided into six classes, each with a specific constellation of characteristics that consistently occur together. Two of these classes have synaptic varicosities with elliptical synaptic vesicles, one in a dense, the other in a sparse matrix, and both make axosomatic and axodendritic synapses. The remaining four classes all have round synaptic vesicles and do not make axosomatic synapses. In the first of these four, the vesicles are tightly packed in a dense matrix, in another they are loosely dispersed, and in the third they are clustered. In the fourth, large granular vesicles predominate. Of these six classes, the most numerous belong to the axons of the Purkinje cell terminal arborization. These boutons resemble their counterparts in the cerebellar cortex, the recurrent collaterals of the Purkinje axon. They have elliptical and flat synaptic vesicles in a dark matrix. The varicosities terminate on somata and dendrites of large and small neurons and constitute the majority of their input. Purkinje axons constitute 86% of the total population of terminals on large neuronal perikarya and 50% of those on their dendrites, but only 78% on the somata of small neurons and 31% on their dendrites. The terminals of climbing fiber collaterals are recognized by their resemblance in electron micrographs to the terminals of the climbing fiber arborization in the cerebellar cortex. They bear round synaptic vesicles packed into a dense axoplasmic matrix and make Gray's type 1 axodendritic synapses with large and small neurons. These axons are restricted to the lateral and ventral aspects of the nucleus and constitute 5% of the terminals on large cell dendrites and 6% of those on small neurons. The axons tentatively identified as collaterals of mossy fibers are myelinated fibers with a light axoplasm containing round synaptic vesicles, dispersed throughout their varicosities. They make Gray's type 1 synapses and constitute a fair percentage of the total axodendritic contacts in the neuropil, 22% on large neurons and 28% on small neurons. The bases for these tentative identifications are discussed in detail, as are the various synaptic relationships undertaken by each class of axon. The remaining 4 classes of axons of the neuropil will be described in subsequent papers.Supported in part by U.S. Public Health Service grants NS 10536 and NS 03659, Training grant NS 05591 from the National Institute of Neurological Diseases and Stroke, and a William F. Milton Fund Award from Harvard University. 相似文献
73.
Dr. T. Mergner L. Deecke H. -J. Wagner 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1981,44(4):455-458
Summary Suggestive evidence as to the site of a major thalamic relay of the vestibular projection to the anterior suprasylvian (ASS) cortex in the cat has been obtained using the retrograde axonal transport of horseradish peroxidase. The thalamo-cortical neurons are located in several patches surrounding the posterior margins of the ventro-basal complex (VB). This area also was found to receive vestibulo-thalamic projections. It comprises different nuclear groups known to carry somatic, accoustic, visual or combined information, which possibly have certain functions related to kinaesthesia and body orientation in common.Abbreviations ANS
ansate sulcus
- ASSS
anterior suprasylvian sulcus
- CM, N
centrum medianum
- CL, N
centralis lateralis
- C.r
Corpus restiformis
- D, N
vestibularis descendens
- i.c., N
intercalatus
- L, N
vestibularis lateralis
- LD, N
lateralis dorsalis
- LG, N
geniculatus lateralis
- LP, N
lateralis posterior
- M, N
vestibularis medialis
- MG, N
geniculatus medialis
- mcMG
pars magnocellularis of MG
- MD, N
medialis dorsalis
- N.c., N
cuneatus
- N. in. VIII, N
interstitialis of the VIIIth cranial nerve
- N. pr. V
principal sensory trigeminal nucleus
- N. tr. sp. V
nucleus of the spinal trigeminal tract
- p.h., N
praepositus hypoglossi
- Pu
pulvinar
- S, N
vestibularis superior
- SG, N
suprageniculatus
- VL, N
ventralis lateralis
- VPL, N
ventralis posterolateralis
- VPM, N
ventralis posteromedialis
- VI, X, XII
motor cranial nerve nuclei
- y, z
small cell groups of Brodal and Pompeiano
Supported by Deutsche Forschungsgemeinschaft, SFB 70 相似文献
74.
本文应用荧光素双标记法研究了后索核、孤束核、三叉神经脊束核向下丘和丘脑投射神经元的分布及其分支投射。作者将Propidium Iodide注入大白鼠右侧丘脑,Bisbenzimide注入右侧下丘,结果如下:楔束核内被标记的神经元中有88.2%向丘脑投射,它们位于核的主部;11.2%向下丘投射,它们在尾侧主要位于核的边缘部,向吻侧(至闩平面)主要位于核的背外侧端。薄束核内被标记的神经元中向下丘投射者(10.9%)与向丘脑投射者(86.7%)混杂在一起。在此两核内仅有极少量分支投射的双标神经元。孤束核和三叉神经脊束核内被标记的神经元中约有2/3投向丘脑,1/3投向下丘,未见分支投射的双标神经元。 相似文献
75.
Matsuo Matsushita Michiko Ikeda 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1970,10(5):501-511
Summary Projections from the spinal gray matter to the cerebellar nuclei in the cat have been studied using Nauta's silver technique. Following unilateral section of the ventrolateral cord at the cervical level, heavy degeneration is seen in the nucleus medialis on both sides. Scanty degeneration is present bilaterally in the nucleus interpositus. The degeneration is most intense on the contralateral side. Scanty degeneration is also present bilaterally in subnucleus medialis parvicellularis (SMP) (Flood and Jansen, 1961). No degeneration is seen in nucleus lateralis. Following unilateral section of the dorsolateral cord at the cervical level, scanty degeneration is present bilaterally in nucleus medialis and nucleus interpositus anterior. The degeneration is more pronounced ipsilaterally and is also seen in SMP on both sides. No degeneration is present in nucleus lateralis. Fibers from the ventral and dorsal spinocerebellar tracts (VSCT and DSCT) terminate bilaterally in nuclei medialis and interpositus, with the VSCT as the most important connection. 相似文献
76.
Postsynaptic fibers reaching the dorsal column nuclei were investigated in rat by means of retrograde transport of wheat germ agglutinin-horseradish peroxidase conjugate. Each nucleus received only ipsilateral afferents with most of the labeled cells forming a band which covered the mediolateral extent of the dorsal horn in an area that resembled lamina IV in the cat. The labeling excluded the reticular extension of the neck of the dorsal horn. Lumbosacral afferents were restricted to the gracilis nucleus and cervicothoracic afferents to the cuneatus nucleus. Cervical and anterior lumbar levels showed additional projections coming from their most medial parts. The organization of this second-order pathway in rat is similar to that in cat and monkey. 相似文献
77.
S. Landgren K. Å. Olsson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1976,26(3):299-318
Summary Extracellular focal potentials were evoked and mapped in the trigeminal motor nucleus and its surrounding borderzone in the cat. Graded electrical stimulation was used for orthodromic and antidromic excitation of the masseteric and digastric motoneurones and for orthodromic stimulation of the lingual and inferior alveolar nerves. The method of referring Horsley Clarke coordinates of microelectrode recording positions to their location of the actual histological section was studied and the total error affecting the method was calculated for the H, AP and L axes. The characteristics and the distribution of the evoked focal potentials were described and related to the histological section from the actual experiment. A phase reversal of the negative focal potential evoked by the lingual and inferior alveolar nerves in the main sensory nucleus and in the intertrigeminal nucleus was observed to indicate the dorso-lateral border of the motor nucleus. Other borders were given by the antidromic potentials evoked in the nucleus. Digastric motoneurones were found medially in the caudal third and ventro-medially in the middle third of the motor nucleus. The masseteric motoneurones were located laterally in the middle and rostral thirds of the nucleus. Potentials evoked in the supratrigeminal and intertrigeminal subnuclei, adjacent to the motor nucleus, were considered and discussed in relation to the available evidence of interneurones subserving trigeminal reflex arcs. 相似文献
78.
Dr. L. Cazin M. Magnin J. Lannou 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1982,48(2):309-313
Summary Radioactive amino-acids were injected into the nucleus reticularis tegmenti pontis (NRTP) and the pretectum (PT) in the rat. Beside the labeling of the several nuclei which are known to receive afferents of either the NRTP and/or the PT, monosynaptic projections from these two structures to the prepositus hypoglossal complex (PHN) were demonstrated. Pretectal visual inputs to the vestibular nuclei (VN) may thus be conveyed not only by the classical PT-inferior olive-cerebellar route, but also by two other non-cerebellar ones involving the strong efferent projections of the PHN onto the VN. These last two pathways are strong candidates to account for the residual visual sensitivity of VN neurons after cerebellectomy or inferior olive lesions.Supported by CNRS (A.T.P. 8115) 相似文献
79.
Dr. I. A. Ilinsky K. Kultas-Ilinsky 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1984,54(1):95-106
Summary Injections of 3H-leucine were made in the entopeduncular nucleus or dentate nucleus of the cerebellum in eight cats. The terminal projection zones of both pathways in the thalamus were studied using the sagittal plane and their relationships to one another as well as to cytoarchitectural boundaries of thalamic nuclei were compared. The data indicate that the territories controlled by the two projection systems are almost entirely segregated. The segregation is mainly along the antero-posterior axis as the main pallidal projection zone occupies the medio-ventral VA while the main dentate projection zone lies posterior to it in the VL. Furthermore, the dorsolateral part of the VA not occupied by pallidal projections receives dentate projections. In the VM, both afferent systems terminate in the lateral part of the nucleus with pallidal territory located anteriorly and dentate territory located posteriorly, again without overlap. As the delineations of nuclear subdivisions in the ventral thalamus of the cat have been a subject of some controversy, it is suggested that the boundaries of the VA, VL and VM in the cat thalamus be defined on the basis of basal ganglia and cerebellar projection zones.Abbreviations used in the Text and in Fig. 5 AM
anterior medial nucleus
- AV
anterior ventral nucleus
- BC
brachium conjunctivum
- CA
anterior commissure
- CC
crus cerebri
- CP
posterior commissure
- CD
caudate nucleus
- CE
centrum medianum
- CLN
central lateral nucleus
- DN
dentate nucleus
- EPN
entopeduncular nucleus
- FF
Forel's field
- FN
fastigial nucleus
- FR
fasciculus retroflexus
- HL
lateral habenular nucleus
- HM
medial habenular nucleus
- INA
anterior interposite nucleus
- INP
posterior interposite nucleus
- IC
internal capsule
- LD
lateral dorsal nucleus
- LG
lateral geniculate body
- MD
medial dorsal nucleus
- MTT
mamillothalamic tract
- NR
red nucleus
- OT
optic tract
- PAC
paracentral nucleus
- PF
parafascicular nucleus
- PV
pulvinar
- RT
reticular thalamic nucleus
- SM
submedian nucleus
- SN
substantia nigra
- SNr
substantia nigra pars reticularis
- STN
subthalamic nucleus
- VF
ventral posterior nucleus
- VA
ventral anterior nucleus
- VL
ventral lateral nucleus
- VM
ventral medial nucleus
- ZI
zona incerta
Supported in part by a grant from the American Parkinson Disease Association and NIH grant R01NS19280 相似文献
80.
目的研究肥厚梗阻型心肌病患者经皮腔内室间隔心肌消融术对心电指标的影响。方法对50例肥厚梗阻型心肌病患者行经皮腔内室间隔心肌消融术,记录术前、术中和术后出现的心律失常类型,配对分析术前、术后心电指标的变化。结果术后与术前相比,QRS时限[(122.0±24.0)ms对(97.3±15.5)ms,P=0.000]明显延长,QTc[(469.3±32.2)ms对(434.3±41.5)ms,P=0.004]、PR间期[(169±26)ms对(162±24)ms,P=0.044]稍延长。术中心律失常发生率分别为:右束支传导阻滞70%(35/50),左束支传导阻滞8%(4/50),一过性AVB38%(19/50),频发室性早搏24%(12/50),短阵室性心动过速24%(12/50);未发生持续性室性心动过速和室颤。术后心律失常发生率分别为:右束支传导阻滞56%(28/50),左束支传导阻滞8%(4/50),交界区性心动过速4%(2/50),频发室性早搏16%(8/50),短阵室性心动过速8%(4/50)。无永久性起搏器植入及死亡病例。结论经皮腔内室间隔心肌消融术致心律失常的发生率高,右束支传导阻滞最为常见。严格选择适应证后谨慎地行PTSMA术是安全、可行的。 相似文献