SEARCH · Search PubMed

Results for “Red Nucleus”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35Linked to original sources

PubMed1983

An anatomical study of the effects of unilateral removal of sensorimotor cortex in infant monkeys on the subcortical projections of the contralateral sensorimotor cortex.

Following removal of the motor or sensorimotor cortex in infant monkeys the projections of the remaining motor or sensorimotor cortex have been studied after long-term survival to look for anomalous projections from these areas. The patterns of degeneration resulting from lesions of the remaining motor or sensorimotor cortex corresponded to those found in normal adult monkeys in the spinal cord, pontine nuclei, superior colliculus, parvocellular red nucleus, subthalamic nucleus and thalamus. Sparse degeneration was found in the magnocellular part of the contralateral red nucleus which has not been described in normal animals and there is also the possibility of an increase in the crossed corticostriate projection. Infant monkeys do not form anomalous projections comparable to those found in the rat following neonatal sensorimotor cortex lesions.

Animals↗

PubMed1994

Electron microscopic demonstration of terminations of posterior thalamic axons on identified rubrospinal neurons in the rat.

In the rat, the major output of the posterior thalamic nucleus (PT) ends in the ventrolateral sector of the rostral two-thirds of the red nucleus. The aim of this study is to identify the rubral cells contacted by these thalamic efferents. In a first set of experiments, an anterograde neurotracer (PHA-L) was injected into the rostral part of the red nucleus. The only structure consistently and densely labeled was the contralateral spinal cord. Therefore, in a second set of experiments, massive HRP injections were made at different cervical levels in the spinal cord in combination with either electrolytic lesion or PHA-L injection in the contralateral PT. Both anterograde and retrograde labelings obtained in the RN were examined by correlated light and electron microscopy. Our findings indicate that anterogradely degenerated or labeled axons arising from the PT form synaptic contacts on HRP-filled dendritic processes of rubrospinal neurons. The thalamo-rubral articulation is direct and seems to be mainly axo-dendritic. These results support the possible participation of the PT in the modulatory control of spinal interneurons through the rubrospinal tract.

Animals↗

PubMed2000

Neuroprotective and neurodestructive functions of nitric oxide after spinal cord hemisection.

Nitric oxide (NO) may subserve different functions in different central neurons subjected to axotomy. The difference may depend on whether the neurons basally express neuronal nitric oxide synthase (nNOS), a biosynthetic enzyme of NO. This is supported by our previous finding that suggests the differential role of NO in neurons of nucleus dorsalis (ND) and red nucleus (RN) which have different basal expression of nNOS. This study aimed to establish firmly the functions of NO, as revealed by nNOS immunoreactivity and nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry, by the administration of endogenous NO donor, l-arginine (l-arg), and NOS inhibitor, l-N(G)-nitroarginine methyl ester (l-NAME). To relate the role of NO to glutamate receptors (GluR), the distributions of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and N-methyl-d-aspartate receptor (NMDAR) in the two nuclei were revealed by immunohistochemical techniques. nNOS immunoreactivity was void in ND neurons, but expressed weakly in the RN normally. It was induced in ipsilateral ND neurons and upregulated on both sides of RN after spinal cord hemisection. Neuronal loss in the ipsilateral ND was augmented by l-arg, but reduced by l-NAME. In the contralateral RN, l-arg attenuated neuronal loss. NMDAR1 was present in most neurons in ND. After axotomy, some NMDAR1 immunoreactive neurons of the ipsilateral ND were induced to express NOS, whereas RN neurons showed strong staining for NMDAR1 and all the AMPA subunits. Most of the NOS-positive neurons in the RN were coexistent with GluR2 in normal rats and those subjected to axotomy. The present data demonstrated that NO exerted neurodestructive function in the non-NOS-containing ND neurons characterized by NMDAR as the predominant glutamate receptor. NO might be beneficial to the NOS-containing RN neurons. This could be attributed to the presence of GluR2. Possible diverse synthesizing pathways of NO in two different central nuclei were suggested from the observation that NOS was colocalized with NADPH-d in ND neurons, but not in RN neurons.

Animals↗

PubMed1983

Properties of cerebello-precerebellar reverberating circuits.

Intracellular recordings were made from neurons of the red nucleus (RN) in cats where the cerebellar cortical effects were removed by chronic ablation of the intermediate part of the anterior lobe of the cerebellum. A prolonged depolarization could be elicited by stimulating the nucleus interpositus (IP) of the cerebellum, nucleus reticularis tegmenti pontis (NRTP) and the nucleus reticularis paramedianus (PMRN). This prolonged depolarization was abolished after cooling the inferior and middle cerebellar peduncles and persisted after ablation of the cerebral sensorimotor cortex. The prolonged depolarization was also recorded intracellularly from IP neurons. It was concluded that the prolonged depolarization set up in RN neurons is due to the repetitive discharges of IP neurons which produces tonic bombardment onto RN cells. The mechanisms of the repetitive discharges of IP neurons are considered to be due to impulse reverberation via the IP. The dynamic properties of the reverberating circuits were characterized by regenerative behavior. Above and below threshold, there were two states, the excited state where many constituent neurons were active, and the resting state where all neurons were inactive. It was found that cats with chronically stimulated cerebral peduncle (CP), and tested in an acute experiment, showed sometimes effective for inducing the prolonged depolarization and repetitive discharges of RN neurons by stimulation of IP. The prolonged depolarization thus produced could be reversibly abolished by cooling the middle and inferior cerebellar peduncles. The possible constituent neurons of the reverberating circuits were investigated in light of previous physiological investigations of stimulating the NRTP, PMRN, nucleus reticularis lateralis (LRN), nucleus olivaris inferior (IO) and recording EPSPs in RN cells. The RN cells receive axon reflex activation from NRTP and PMRN, and disynaptic excitation from NRTP, PMRN, LRN and IO. Based on these and other available data, the components of the cerebello-precerebellar reverberating circuits are discussed.

Animals↗

PubMedDate not supplied

Morphology of single neurones in the cerebello-rubrospinal system.

Axonal branching patterns of physiologically identified cerebellar nucleus neurones and rubrospinal neurones were investigated in the cat with intra-axonal injection of horseradish peroxidase and 3-dimensional reconstruction on serial sections. Axons of dentate and interpositus neurones projected to the VL nucleus of the thalamus and on their way, several axon collaterals were given off from the stem axons to the red nucleus. Axon terminals of interpositus neurones terminated as a sagittal sheet of arborizations in the red nucleus. Their terminal boutons made apparent contact with cell bodies and proximal dendrites of rubrospinal neurones. In rubrospinal axons, multiple axon collaterals were identified at different segments of the cervical spinal cord.

Animals↗

PubMedDate not supplied

The substantia nigra in Parkinson disease: proton density-weighted spin-echo and fast short inversion time inversion-recovery MR findings.

BACKGROUND AND PURPOSE: A reduction in the area of the substantia nigra (SN) has been shown in patients with Parkinson disease. The substantia nigra is anteroinferolateral to the red nucleus, and it is important to precisely locate its true anatomic location to accurately measure SN area. Our purpose was to determine the exact location of the substantia nigra by correlating imaging and anatomic findings. We also attempted to quantitate SN area in patients with Parkinson disease compared with that in healthy control subjects on the basis of proton density-weighted spin-echo (SE) and fast short inversion time inversion-recovery (STIR) MR imaging findings. METHODS: In four healthy volunteers, dual-echo SE and fast STIR MR images were obtained in three orthogonal planes and an oblique coronal plane. These images were correlated with anatomic specimens to determine the location of the SN. The area of the SN was also measured on oblique coronal fast STIR images obtained at a plane perpendicular to the SN in 22 patients with Parkinson disease and in 22 age- and sex-matched healthy volunteers. RESULTS: The true anatomic location of the SN, anteroinferolateral to the red nucleus, was accurately identified, not on T2-weighted images, but on proton density-weighted SE images and fast STIR images as an area of hyperintense gray matter. The hypointense area seen on T2-weighted images corresponded to the anterosuperior aspect of the SN and to the adjacent crus cerebri. No statistically significant differences were noted in the size of the SN when the oblique coronal images of patients with Parkinson disease were compared with those of the control groups. CONCLUSION: The SN is located mainly beneath the red nucleus. Its location cannot be determined on the basis of T2-weighted imaging results but rather on the basis of proton density-weighted SE or fast STIR findings. SN volume loss is not found in Parkinson disease, and this finding is compatible with that of recent pathology reports in the literature.

Adult↗

PubMed1982

[Distribution and characteristics of the axonal collaterals of the rubrospinal neurons at the brain stem level].

In acute experiments on cats, intracellular recording of antidromic APs and the collision test, analysis of correlation between the time of antidromic conduction along the axon's main stem before and after collateral branching as well as the time of conduction in collaterals themselves, revealed a tendency to synchronous arrival of rubrospinal impulses to various brain stem centers at the expense of increased conduction velocity in response to lengthened distance between the brain stem structures and the red nucleus. The data obtained is discussed in the light of sensomotor integration mechanisms and role of the red nucleus in planning and actualization of the motor act.

Animals↗

PubMed1979

The rubro-olivo-cerebellar teaching circuit.

The hypothesis proposes a neural teaching circuit, and invokes the parvocellular Red Nucleus as the key nucleus in that circuit acting on the inferior olivary nucleus to maintain the efficiency of motor learning in primates, while acknowledging the inferior olive to be the key nucleus by which learning instructions go to Purkinje cells in the cerebellar cortex. Anatomical, physiological and pathological data is reviewed in an attempt to attribute a function to the evasive parvocellular Red Nucleus.

Animals↗

PubMed1998

['Rubral' tremor after vascular thalamic lesions].

INTRODUCTION: The appearance of tremor after thalamic lesions is well-known but infrequent. Amongst the semiological varieties of thalamic tremors, a particularly uncommon type--which is extremely incapacitating owing to its great amplitude, appearance during action and poor therapeutic response--is the so-called rubric or mesencephalic tremor. CLINICAL CASES: We present four cases, of tremor with the semiological characteristics of rubric tremors after thalamic lesions of ischaemic or haemorrhagic origin. We review the relevant literature. DISCUSSION: The rubric tremor has been said to have its physiopathological origin in a lesion of the nigro-striate via and the efferent cerebellar vias at some point of the mesencephalic or subthalamic path, often without direct involvement of the red nucleus. CONCLUSIONS: The presentation of this type of tremor due to lesions which do not effect the red nucleus and the mesencephalum show the unsuitability of the name.

Aged↗

PubMed1997

[(Neurological CPC.55). A 60-year-old woman with progressive cerebellar ataxia, myoclonus, and dementia].

We report a 60-year-old woman with progressive ataxia, myoclonus, choreoathetosis, and dementia. She was well until 27 years of the age when she noted an onset of gait disturbance and speech disturbance. She noted abnormal involuntary movements in her four limbs at 42 years of the age. Her symptoms had progressively become worse and she fell down frequently by her 52 years of the age. In addition, her family members noted gradual decline in her intelligence. She was admitted to our hospital in February of 1993 when she was 57-year-old. On admission, she showed dementia, scanning speech, ataxic gait, limb ataxia, action myoclonus, and choreic movements which involved her four limbs. Deep tendon reflexes were slightly exaggerated in the lower limbs; no Babinski sign was noted. Sensation was intact. Laboratory findings were unremarkable. Cerebral MRI revealed atrophy of the cerebellar cortex, superior cerebellar peduncle, brain stem, and the cerebral cortex; the third ventricle and the lateral ventricles were dilated; furthermore, T2-high signal lesions were seen in the cerebral white matter and in the pontine base. Her clinical course was one of the progressive deterioration of her ataxia, involuntary movements, and dementia. She expired on April 24, 1996 when she was 60-year-old. She was discussed in a neurologic CPC and the chief discussant arrived at the conclusion that the patient had dentatorubral-pallidoluysian atrophy. A minor opinion was that she might have had myoclonus epilepsy with ragged-red fibers. Postmortem examination revealed atrophy, gliosis, and neuronal loss in the external segment of the globus pallidus, subthalamic nucleus, red nucleus, and in the dentate nucleus. In addition, the gracil and cuneiform nuclei showed neuronal loss and spheroid formation; the spinocerebellar tracts were retained. The substantia nigra and the locus coeruleus were intact. No ragged-red fibers were seen in the muscle biopsy specimen taken in February, 1993. The neuropathologic findings were consistent with the diagnosis of dentatorubral-pallidoluysian atrophy.

Atrophy↗

PubMed1983

Anatomical demonstration of the location and collateralization of rubral neurons which project to the spinal cord, lateral brainstem and inferior olive in the North American opossum.

Rubral neurons innervating the spinal cord, the lateral brainstem and the inferior olivary nucleus have been identified in the North American opossum by the retrograde transport of horseradish peroxidase and fluorescent markers. Neurons which project to the spinal cord are found mainly in caudal and rostroventral parts of the red nucleus. In contrast, rubral neurons which innervate the facial nucleus and lateral areas of the medulla are most numerous rostrodorsally. There is overlap in the location of rubral neurons which project to the spinal cord and lateral brainstem, however and; double-labelling techniques show that some rubral neurons provide collaterals to both areas. Neurons which innervate the inferior olive are located primarily in rostromedial portions of the red nucleus with some overlap with those innervating the spinal cord. Few rubral neurons provide collaterals to both the spinal cord and inferior olive.

Animals↗

PubMed1996

Perineuronal microglial reactivity following proximal and distal axotomy of rat rubrospinal neurons.

Microglial reactivity in the red nucleus of rats was studied following upper cervical and lower thoracic rubrospinal tractotomy using the lectin binding method. Following axotomy, the contralateral nucleus containing the axotomized neurons was identified using the retrograde tracer Fast blue. It was subdivided into dorsomedial (DM) and ventrolateral (VL) portions known to project to the cervical and lumbar spinal cord, respectively. Lectin-labeled microglial cells and processes on the contralateral as well as in the ipsilateral nucleus were then quantified. An early and a late increase in microglial reactivity was observed in the nucleus at 2-5 days and 2-8 weeks following thoracic and cervical tractotomy with the latter producing a more pronounced reactivity. In rats subjected to thoracic axotomy, a similar microglial increase also occurred in the intact contralateral DM nuclear area suggesting the possible action of diffusable factor(s) that might have triggered the microglial activation from the axotomized VL nuclear area. The uninjured ipsilateral nucleus also exhibited a similar pattern of microglial reactivity irrespective of the number of ipsilaterally projecting neurons following both cervical and thoracic axotomy. This could have been elicited by the retrograde influence from the denervated targets carried by the intact rubrospinal fibers of the opposite side since many of them in fact terminate bilaterally (Antal, M. et al., J. Comp. Neurol., 325 (1992) 22-37). In all the axotomized or intact nucleus, microglial processes did not appear to surround neuronal cell bodies. The characteristic responses of microglial cells in the red nucleus may be related to the failure of rubrospinal neurons to regenerate following the severance of their axons.

Amidines↗

PubMed1976

Incorporation of tritiated leucine by axotomized rubral neurons.

Fourteen kittens, 7--10 weeks of age, were injected with [3H]leucine 0.5--24 h before sacrifice 1--30 days after unilateral high cervical rubrospinal tractotomy. Histoautoradiographs of the red nuclei were prepared and counterstained with thionin. Axon reaction, evident histologically 24 h after surgery, was manifested by central chromatolysis or diffuse cytoplasmic chromophobia. Partial reversion toward a normal cytologic appearance was apparent 10--30 days postoperatively. Nucleolar and nuclear shrinkage and cytoplasmic atrophy were conspicuous accompaniments of axon reaction in rubral neurons. Expressed per cell the radioactivity of axotomized rubral nerve cells was consistently less than controls in animals surviving operation from 5 to 30 days. The data indicate that axon reaction in red nucleus is regressive in character and early associated with diminished protein synthesis. The frequently regressive nature of axon reaction in intrinsic neurons, such as those of red nucleus, probably is important in accounting for failure of regeneration of many mammalian CNS fiber tracts after injury.

Animals↗

PubMed2002

Mesencephalic projections to the first cervical segment in the cat.

Mesencephalic neurons projecting to the upper cervical spinal cord were examined by mapping the distributions of labeled cells after injecting fluorescent tracers or wheat-germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) into the C1 segment. Injections into the central or deep regions of the ventral horn produced retrograde labeling in cells of several mesencephalic regions. The majority of cells were found contralaterally in the superior colliculus and red nucleus, and ipsilaterally in and around the interstitial nucleus of Cajal (INC), in the cuneiform region, and in the fields of Forel. Smaller numbers of cells were located in the periaqueductal gray matter, nucleus annularis, and magnocellular nucleus of the posterior commissure. Dorsomedial injections in the ventral horn near the ventral commissure labeled only a subset of these projections, including cells in the mesencephalic reticular formation adjacent to the INC and in the nucleus annularis. Dorsolateral injections labeled some cells in the superior colliculus and were particularly effective at labeling cells in the red nucleus. These results suggest that at least ten different cell groups project to the ventral horn of the first cervical segment. Most, but not all, groups originate from regions implicated previously in the control of eye or head movements.

Animals↗

PubMed2003

Brain afferents to the lateral caudal ventrolateral medulla: a retrograde and anterograde tracing study in the rat.

The ventrolateral medulla (VLM) modulates autonomic functions, motor reactions and pain responses. The lateralmost part of the caudal VLM (VLMlat) was recently shown to be the VLM area responsible for pain modulation. In the present study, the brain sources of VLMlat afferent fibers were determined by tract-tracing techniques. Following injection of cholera toxin subunit B into the VLMlat, retrogradely labeled neurons in the forebrain occurred at the somatosensory, insular, motor, limbic and infralimbic cortices, and at the central amygdaloid nucleus. Retrogradely labeled neurons in diencephalic regions were observed in the lateral hypothalamus, posterior hypothalamus and paraventricular nucleus. In the brainstem, retrograde labeling occurred at the periaqueductal gray, red nucleus, parabrachial area, nucleus raphe magnus, nucleus tractus solitarii, lateral reticular nucleus and dorsal and ventral medullary reticular formation. In the cerebellum, retrogradely labeled neurons occurred at the lateral nucleus. Following injections of the anterograde tracer biotinylated dextran amine (BDA) into the lateral hypothalamus or paraventricular nucleus, anterogradely labeled fibers were mainly observed in the VLMlat. Injections of BDA into the periaqueductal gray, red nucleus or lateral nucleus of the cerebellum resulted in anterograde labeling in the VLMlat and lateral reticular nucleus. The present study gives an account of the brain regions putatively involved in triggering the modulatory actions elicited from the VLMlat. These include areas committed to somatosensory processing, autonomic control, somatic and visceral motor activity and affective reactions. The findings suggest that the VLMlat may play a major homeostatic role in the integration of nociception with other brain functions.

Adjuvants, Immunologic↗

PubMed1978

The synaptic terminations of certain midbrain-olivary fibers in the opossum.

The nuclear origin and distribution of midbrain-olivary fibers has been described in a previous study utilizing axonal transport techniques (Linauts and Martin, '78a). The present report extends their results to the electron microscopic level and details the postsynaptic distribution of such fibers. Lesions within the ventral periaqueductal grey and adjacent tegmentum, the red nucleus or the nucleus subparafascicularis result in electron dense axon terminals within the olive at survival times of 48, 72 and 96 hours. At 72 hours, many degenerating presynaptic profiles shrink, become irregular in shape and are totally or partially surrounded by glial processes. The principal olivary nucleus contains the majority of these profiles. However, the subparafascicular terminals are more abundant in the rostral and intermediate parts of the medial accessory nucleus and the rubral terminals are concentrated within the dorsal lamella of the principal nucleus. The nuclear location of the degenerating terminals was determined by examination of 1 micrometer plastic sections cut in the transverse plane from each block face prior to thin sectioning. Degenerating terminals were counted in three cases, one from each of the three lesion sites described above. When taken together these cases show that just over 50% of the degenerating terminals are presynaptic to spiny appendages and are located within the synaptic clusters (glomeruli) described previously (King, '76). The percentage of degenerating terminals in the glomeruli increases to 70% when the lesion is in the ventral periaqueductal grey and adjacent tegmentum. The remaining degenerating terminals contact dendritic shafts outside the astrocytic boundaries of the synaptic clusters. The synpatic vesicle populations within the degenerating terminals vary with the location of the lesion. Lesions in the ventral periaqueductal grey and the adjacent tegmentum result in the degeneration of terminals with either clear spherical vesicles or endings with both clear spherical vesicles and a variable number of large dense core vesicles. In contrast, the primary degenerative changes that occur after destruction of the red nucleus or the nucleus subparafascicularis are in terminals with clear spherical vesicles. When the synaptic complex was present in the plane of section, regardless of the site of the lesion, the degenerating terminals could be classified as Gray's type I. Thus, we have demonstrated that afferents from the mesencephalon terminate within synpatic clusters located in the principal and medial accessory (part A) subnuclei of the inferior olive. Although the mesencephalic afferents have multiple origins (Linauts and Martin, '78a), many of their synaptic terminals contact spiny appendages within the synaptic clusters. This postsynaptic site also receives cerebellar terminals (King et al., '76). The origin of presynaptic profiles within the synaptic clusters that contain clear pleomorphlic vesicles is yet to be determined.

Animals↗

PubMed1985

Histochemical and ultrastructural features of neuronal pigment in some encephalic nuclei of ruminants.

Neuronal pigment in red nucleus, locus coeruleus and substantia nigra from cattle, sheep and goat was examined with the aid of light and electron microscopy. In the red nucleus and locus coeruleus neurons of all the species examined the pigment shows the histochemical and ultrastructural features typical of lipofuscins. The ultrastructural observations indicated that the morphology of pigment granules is related to age and permitted identification of various stages of pigment evolution, which suggested a lysosomal origin of the pigment bodies. In bovine and sheep the substantia nigra is very reduced and contains no detectable pigment; while in goat, some neurons appear to contain discrete amounts of neuromelanin. Ultrastructurally this kind of pigment appears characterized by the features of a lipofuscin-like granule which stores highly electron dense material identifiable as melanin.

Age Factors↗

PubMed1987

[Neuronal analysis of the rubro-cerebellar projection in the cat].

Antidromic activation of red nucleus neurons evoked by stimulation of cerebellar nucleus interpositus was studied in nembutalized cats. Neuronal composition of the rubro-cerebellar projection was shown to be determined by two types of red nucleus cells. One is represented by rubro-spinal neurons with axon collaterals projecting to cerebellar nucleus interpositus and affected by synaptic influences from the cerebral cortex and cerebellum. The other component of rubro-cerebellar projection is represented by nonrubro-spinal neurons having no synaptic inputs from the cerebral cortex and cerebellum.

Animals↗