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  • Key words Amyotrophic lateral sclerosis  (9)
  • C3-C4 propriospinal neurones  (4)
  • 1
    Electronic Resource
    Electronic Resource
    Dendritic synapses of anterior horn neurons in amyotrophic lateral sclerosis: an ultrastructural study (1996)
    Springer
    Acta neuropathologica 91 (1996), S. 278-283 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Primary dendrite ; Synapse ; Synaptic length ; Active synaptic zone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This ultrastructural study deals with the synapses of primary dendrites of the anterior horn neurons in the lower lumbar spinal cords of seven patients with amyotrophic lateral sclerosis (ALS) who had mild neuronal depletion. Specimens from seven age-matched, neurologically normal individuals served as controls. In each instance, the autopsy was performed within 6 h after death. Our results indicate a statistically significant increase in degenerative changes in the dendrite presynapses of normal-appearing neurons of the ALS patients. The alterations included aggregation of electron-dense synaptic vesicles and dark mitochondria with dense cristae, and bundles of neurofilaments. However, we found no significant difference between controls and patients with respect to cross-sectional area and length of the dendrites, number of synapses per dendrite, and lengths of individual synapses and their active zones in the normal-appearing neurons, even though the patients' neurons had a smaller cross-sectional area. In chromatolytic neurons, the number of synapses and the length of the active zone of the primary dendrites were significantly diminished. These findings suggest that despite degenerative changes of the presynapses, the synapses in the primary dendrites of the anterior horn neurons are preserved at the early stage of ALS. The preservation of these synapses may be due to their relative resistance to degenerative processes, or may represent a compensatory mechanism of the synapses for diminished synaptic function in distal dendrites.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050426
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  • 2
    Electronic Resource
    Electronic Resource
    Synapse loss in anterior horn neurons in amyotrophic lateral sclerosis (1994)
    Springer
    Acta neuropathologica 88 (1994), S. 222-227 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Anterior horn neuron ; Synapse ; Active zone ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This report deals with an ultrastructural investigation of the synapses of anterior horn neurons in the lumbar spinal cords of five patients with amyotrophic lateral sclerosis (ALS) who had mild neuronal depletion. Specimens from five age-matched, neurologically normal individuals served as controls. In each instance, the autopsy was performed within 3 h after death. A statistically significant decrease in cell body area, number of synapses and total synaptic length was found in the normal-appearing neurons of the ALS patients. The alterations were more pronounced in neurons with central chromatolysis. However, despite an approximately 20  % reduction in the number of synapses, the length of the active synaptic zone of the normal-appearing neurons in the ALS patients was not diminished. This observation may be accounted for by a plasticity to the loss of synapses which maintained the active zone of the remaining synapses to increase synaptic efficiency. It is suggested that when the plasticity of the active zone reaches its limit, the continuing loss of synapses may lead to functional impairment. The capacity of the active synaptic zone to respond to progressive denervation of the anterior horn neurons may preserve motor function or slow the development of motor deficits in the early stage of degeneration of the lower motor neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00293397
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  • 3
    Electronic Resource
    Electronic Resource
    Synaptic loss in the proximal axon of anterior horn neurons in motor neuron disease (1995)
    Springer
    Acta neuropathologica 90 (1995), S. 170-175 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Motor ; neuron disease ; Axon hillock ; Initial segment ; Synapse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This report deals with an ultrastructural investigation of the synapses of the proximal axons of normal-appearing anterior horn neurons of 7 patients with amyotrophic lateral sclerosis (ALS) and 4 patients with motor neuron disease who had no upper motor neuron and corticospinal tract involvement (lower motor neuron disease, LMND). Specimens from 12 age-matched individuals who died of non-neurological diseases served as controls. Proximal axons directly emanating from the normal-appearing neurons were examined: 42 axons were from ALS patients, 43 from LMND patients and 87 from controls. Our results show that the number of synapses on axon hillocks, as well as the lengths of the synaptic contact and of the active zone were reduced in both groups of patients (P 〈 0.0001), but no significant differences were seen between patients and controls with respect to the synaptic parameters of initial axon segments. There was no overall difference between ALS and LMND patients. These findings suggest that the electrophysiological functions pertaining to integration of electrical inputs into the axon and information transduction on the axon may be greatly impaired in the early stages of motor neuron diseases, and that the observed synaptic alterations may be pathological events, likely to be due to anterior horn neuron degeneration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00294317
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  • 4
    Electronic Resource
    Electronic Resource
    Immunoreactivity of β-amyloid precursor protein in amyotrophic lateral sclerosis (1999)
    Springer
    Acta neuropathologica 97 (1999), S. 463-468 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; β-Amyloid precursor protein ; Immunohistochemistry ; Fast axonal transport ; Anterior horn neuron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We investigated the localization and extent of β-amyloid precursor protein (β-APP695) immunoreactivity as a sensitive marker for impairment of fast axonal transport in the spinal cords of 21 patients with amyotrophic lateral sclerosis (ALS), paying special attention to anterior horn neurons. Specimens from 18 patients without neurological disease served as controls. Increased β-APP immunoreactivity was frequently recognized in the anterior horns of the ALS patients with short clinical courses or with mild depletion of anterior horn cells, while no β-APP immunoreactivity was demonstrated in those with severe depletion of anterior horn neurons or with long-standing clinical courses. Increased β-APP immunoreactivity in the anterior horn neurons was mainly confined to the perikarya and no immunoreactivity was recognized in the dendrites or proximal axons directly emanating from the somata, except some spheroids (proximal axonal swellings) which showed increased immunoreactivity of β-APP. Increased β-APP immunoreactivity was spotted or focally aggregated in the perikarya of normal-looking large anterior horn neurons, while it was frequently diffuse in that of degenerative neurons such as central chromatolytic cells and or those with simple atrophy. On the other hand, the controls showed no immunostaining with β-APP in the spinal cord. These findings suggest that increased immunoreactivity of β-APP in neuronal perikarya of the anterior horn cells and in some proximal axonal swellings is an early change of ALS, and may be a response of the increased synthesis of β-APP resulting from neuronal damage, or the impairment of fast axonal transport.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010051015
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  • 5
    Electronic Resource
    Electronic Resource
    Immunocytochemical and ultrastructural study of pericapillary rosettes in amyotrophic lateral sclerosis (1997)
    Springer
    Acta neuropathologica 94 (1997), S. 338-344 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Pericapillary rosette ; Immunocytochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This report concerns a comparative immunocytochemical and ultrastructural investigation on pericapillary rosettes (PR) in the lumbar spinal cords of 21 patients with amyotrophic lateral sclerosis (ALS) and 18 age-matched neurologically normal individuals. The purpose of the study was to determine the alteration of PR in relation to the neuronal loss in ALS. The PR were almost always positively immunostained for phosphorylated neurofilament, and some PR immunoreacted with antibodies to synaptophysin and β-amyloid precursor protein. This finding suggests that axonal transport, whether fast or slow, is impaired in the terminal portion of the axon that reaches the capillaries. Some PR were also positively immunostained by the antibody against ubiquitin, anti-calbindin-D 28 K antibody, anti-parvalbumin antibody and the antibody to superoxide dismutase 1. Morphometrically, the number of PR in the anterior horns and lateral column was markedly diminished in ALS compared with controls. At the ultrastructural level, the PR consisted mostly of unmyelinated degenerated axons, and were frequently found outside the basal laminae of the endothelial cell and of the astrocytic foot processes on the opposite side of the capillary, and less often in the space between the two basal laminae. The data indicate that the fate of PR is intimately associated with the neuronal loss of the anterior horn cells and with degenerative change of nerve fibers extending from their mother neurons to the capillaries.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050716
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  • 6
    Electronic Resource
    Electronic Resource
    Characterizations of heterotopic neurons in the spinal cord of amyotrophic lateral sclerosis patients (1998)
    Springer
    Acta neuropathologica 95 (1998), S. 367-372 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Heterotopic neuron ; Alpha motor neuron ; Immunocytochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This report concerns a comparative immunocytochemical, ultrastructural and morphometric investigation on heterotopic neurons in the white matter of the spinal cords of 19 patients with amyotrophic lateral sclerosis (ALS) and 18 age-matched neurologically normal individuals. The study revealed that the heterotopic neurons were scattered in the white matter, often adjacent to gray matter, that they immunoreacted with the antibody to synaptophysin, and that there were synaptic apparatuses on the surface of their somata and their neuronal processes. Bunina bodies and ubiquitin-positive inclusions such as Lewy body-like inclusions and skein-like inclusions, characteristic of anterior horn neurons of ALS, were present in the cytoplasm of the patients’ heterotopic neurons in the anterior or lateral column of the white matter. These findings suggest that heterotopic neurons in the anterior or lateral column have the characteristics of alpha motor neurons. The average number of heterotopic neurons observed in ALS patients was generally less than in normal subjects. This reduction was correlated with the severity of neuronal loss. The heterotopic neurons in ALS were less susceptible to the degenerative process as compared with spinal cord anterior horn cells. We assume that in this disease the heterotopic neurons may be degenerated and their number diminished after or concomitantly with the depletion of anterior horn neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050812
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  • 7
    Electronic Resource
    Electronic Resource
    Motor neuron disease with predominantly upper extremity involvement: a clinicopathological study (1999)
    Springer
    Acta neuropathologica 98 (1999), S. 645-650 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Autopsy ; Electron microscopy ; Immunocytochemistry ; Motor ; neuron disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report two autopsy cases of motor neuron disease (MND) patients with an unusual type of muscular atrophy predominantly affecting the shoulder girdle and the upper extremities with proximal dominance. Both patients are considered to be clinically categorized into the El Escorial suspected form of amyotrophic lateral sclerosis (ALS). At autopsy, they showed marked loss of spinal anterior horn cells accompanied by astrogliosis positively immunostained with anti-glial fibrillary acidic protein antibody at the cervical level. At the lumbosacral level, anterior horn neurons were relatively well preserved and Bunina bodies, ubiquitin-positive skein-like inclusions and Lewy body-like inclusions were observed in the remaining neurons. In one patient, brain stem motor neurons (nerves V, VII, XII) and motor cortex, including Betz cells, were also affected and the corticospinal tracts were degenerated at the level of the thoracic and lumbar spinal cord. Pathological findings of this patient are consistent with those of ALS. In the other patient, the motor cortex, brain stem motor nuclei and the corticospinal tracts were well preserved, which is pathologically compatible with progressive spinal muscular atrophy. These patients with such a peculiar pattern of progressive muscular atrophy should be placed in a subgroup of ALS.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010051131
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  • 8
    Electronic Resource
    Electronic Resource
    Integration in descending motor pathways controlling the forelimb in the cat (1984)
    Springer
    Experimental brain research 56 (1984), S. 308-322 
    Details
    ISSN: 1432-1106
    Keywords: Descending pathways ; Forelimb afferents ; C3-C4 inhibition ; C3-C4 propriospinal neurones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Extra- and intracellular recording was made from cells in the C3-C4 segments with the aim of finding interneurones of previously described inhibitory pathways to the C3-C4 propriospinal neurones, which may mediate descending feed-forward inhibition and feed-back inhibition from the forelimb, respectively. The lateral interneurones were found in the lateral part of lamina VII interspersed among the C3-C4 PNs and like them they receive convergent monosynaptic EPSPs and disynaptic IPSPs from the cortico-, rubro-, tecto- and reticulospinal tracts. Disynaptic IPSPs, but only rarely monosynaptic EPSPs, are evoked in them from forelimb nerves. The lateral interneurones do not project to the lateral reticular nucleus (LRN). The medial interneurones were found medially in laminae V and VI in a region where volleys in forelimb nerves evoke extracellular monosynaptic focal potentials (Rosén 1969). There is somatotopic organization of the projection from the forelimb to this region. Many neurones are strongly monosynaptically excited from group I muscle or/and cutaneous forelimb afferents. In addition, late discharges are evoked in many cells from cutaneous afferents and high threshold muscle afferents. Corticospinal volleys evoked monosynapic excitation in the great majority of these cells and usually also late EPSPs or IPSPs. Typically, rubrospinal and tectospinal volleys evoked neither monosynaptic excitation nor late effects as those elicited from corticospinal fibres. In some of the interneurones, IPSPs were evoked from forelimb nerves. About 20% of the medial “interneurones” have an ascending projection to the caudal brain stem. Threshold mapping for antidromic stimulation revealed termination in the main cuneate nucleus, the external cuneate nucleus and/or the LRN and also a branch projecting to more rostral levels in the brain. A few of the neurones in the medial region are PNs projecting to the forelimb segments. It is postulated that interneurones both of the lateral and medial type are inhibitory and project to the C3-C4 PNs. It is further postulated that the former are intercalated in the descending feed-forward inhibitory pathway to the C3-C4 PNs and the latter in the feed-back inhibitory pathway from the forelimb to these PNs. The role of feed-forward and feed-back inhibition of transmission from the brain to forelimb motoneurones via the C3-C4 PNs is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00236286
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  • 9
    Electronic Resource
    Electronic Resource
    Integration in descending motor pathways controlling the forelimb in the cat 15. Comparison of the projection from excitatory C3-C4 propriospinal neurones to different species of forelimb motoneurones (1986)
    Springer
    Experimental brain research 63 (1986), S. 543-556 
    Details
    ISSN: 1432-1106
    Keywords: C3-C4 propriospinal neurones ; Excitatory projection ; Forelimb motoneurones ; Lateral reticular nucleus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the preceding report (Alstermark and Sasaki 1986) it was shown that a stimulus of 500 μA applied in the lateral reticular nucleus (LRN) evokes a maximal or near monosynaptic EPSP (LRN EPSP) in forelimb motoneurones. This EPSP which is assumed to be selectively mediated by C3-C4 propriospinal neurones (PNs), was used to estimate the strength of the excitatory projection from C3-C4 PNs. A systematic comparison was made of the size and time course of the maximal LRN EPSP in various species of forelimb α-motoneurones innervating shoulder, elbow, wrist and digit muscles. The LRN EPSP was evoked in all investigated species of forelimb motoneurones. When either the peak amplitude or the underlying area of the LRN EPSP was compared, a three-fold range was found with some tendency for the size to vary in the order of wrist 〉 shoulder ≈ elbow 〉 digit 〉 intrinsic paw motor nuclei. Generally, a positive correlation was found in each motor nucleus between the peak amplitude of the LRN EPSP versus the monosynaptic homonymous group Ia EPSP, input resistance and afterhyperpolarization duration respectively (cf. Alstermark and Sasaki 1986). It is therefore postulated, that the LRN EPSP peak amplitude is correlated with motor unit type. Comparison of the time course of the LRN EPSPs was made by measuring the time-to-peak (T-t-p) and half-width (H-w). The finding in the preceding report that the T-t-p and H-w is longer in slow than in fast motoneurones was confirmed and extended to all the investigated motor nuclei. The hypothesis that both fast slow motoneurones receive projection from a group of fast C3-C4 PNs, while slow motoneurones receive an additional projection from a group with lower conduction velocity, can therefore be applied to all forelimb motor nuclei. In addition, it is proposed that some slow shoulder, wrist and digit motoneurones receive projection from a special subpopulation of C3-C4 PNs with very slow conduction velocity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00237477
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  • 10
    Electronic Resource
    Electronic Resource
    Integration in descending motor pathways controlling the forelimb in the cat 14. Differential projection to fast and slow motoneurones from excitatory C3-C4 propriospinal neurones (1986)
    Springer
    Experimental brain research 63 (1986), S. 530-542 
    Details
    ISSN: 1432-1106
    Keywords: C3-C4 propriospinal neurones ; Differential projection ; Fast and slow forelimb motoneurones ; Lateral reticular nucleusn
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The projection of C3-C4 propriospinal neurones (PNs) to α-motoneurones of forelimb muscles has been analysed with the aid of antidromic stimulation of the ascending branch of the PNs to the lateral reticular nucleus (LRN). A single stimulus of 500 μA applied in the caudo-dorsal part of the LRN evoked a maximal or 〉 90% maximal monosynaptic EPSP in the motoneurones. Systematic mapping of EPSPs evoked by stimulation of 500 μA in and around the LRN revealed that at this strength there was hardly any co-activation of a medial system (Peterson et al. 1979) which evoked small monosynaptic EPSPs with shorter latency and faster time course. The LRN EPSP amplitude was positively correlated with the homonymous group Ia EPSP amplitude, the input resistance and the afterhyperpolarization (AHP) duration. It is therefore postulated that the LRN EPSP amplitude is correlated with motor unit type (Burke 1967, 1968; Burke et al. 1973) with the largest EPSPs in slow (S), the smallest in fast, fatiguable (FF) and possibly intermediate sized in fast, fatigue resistant (FR) units. There was only a small difference in latency of the LRN EPSP in fast and slow motoneurones, while the time course was considerably slower in the latter. It is suggested that slow motoneurones receive projection both from fast and slowly conducting PNs but fast motoneurones mainly from fast PNs. Comparison of the disynaptic pyramidal EPSPs and the LRN EPSPs revealed a positive correlation, but the amplitude ratio pyramidal EPSP: LRN EPSP was smaller in slow than in fast motoneurones. A negative correlation was found between this amplitude ratio and the latency of the disynaptic pyramidal EPSP. It is suggested that this correlation reflects the excitability level in the PNs and that low excitability is due to inhibition of the PNs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00237476
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