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J Arvidsson

Publications and source records attributed to J Arvidsson.

At least 55 records · Page 3Linked to original sources
PubMed1989

An HRP study of the central projections from primary sensory neurons innervating the rat masseter muscle.

Retrograde and transganglionic transport of horseradish peroxidase has been used to study the cell bodies of origin and the central projections of neurons innervating the rat masseter muscle. Labeled cell bodies were observed both in the trigeminal ganglion and in the mesencephalic trigeminal nucleus. Major central projections from mesencephalic trigeminal neurons were traced to the supratrigeminal nucleus and to the brainstem reticular formation. Smaller projections from these neurons could be followed to the borders of the solitary tract and hypoglossal nuclei as well as to lamina V of nucleus caudalis and corresponding areas in the dorsal horn at C1-C2 spinal cord segments. Labeling from trigeminal ganglion neurons was observed close to the trigeminal tract in all subdivisions of the trigeminal sensory nuclear complex and in the dorsal horn lamina I at C1 and C2 levels.

Animals↗
PubMed1989

Combined retrograde tracing and enzyme/immunohistochemistry of trigeminal ganglion cell bodies innervating tooth pulps in the rat.

Rat trigeminal neurons innervating tooth pulps were retrogradely labelled with fluorogold and analysed enzyme- and immunohistochemically for their content of substance P, calcitonin gene-related peptide, fluoride-resistant acid phosphatase, GM 1 ganglioside, carbonic anhydrase and neurofilament protein. The data showed that both small, medium-sized and large trigeminal neurons were labelled after fluorogold deposition in maxillary molar pulps, with a majority of the cells being medium-sized and large. Less than 2% of the pulpal neurons showed substance P-like immunoreactivity. Fifty-six per cent of the pulpal nerve cells were calcitonin gene-related peptide-positive. These cells were small, medium-sized and large. Only 1% of the fluorogold-labelled cells contained fluoride-resistant acid phosphatase enzyme activity. This paralleled the finding that the pulpal neurons were unstained by Griffonia simplicifolia isolectin I-B4, a plant lectin which preferentially binds to fluoride-resistant acid phosphatase-positive cells. Choleragenoid-like immunoreactivity, which identifies cells with the GM 1 ganglioside receptor, was found in 70% of the fluorogold-labelled pulpal neurons. Approximately 80% of the fluorogold-labelled cells showed RT 97-immunoreactivity. RT 97 labels neurofilament protein and is present in large light primary sensory neurons. No pulpal neurons appeared to contain carbonic anhydrase, as judged from both enzyme- and immunocytochemical observations. The findings suggest that, in the rat, trigeminal tooth pulp neurons, which according to the classical view are nociceptive, form a heterogeneous group of neurons with a minority of small cells which may contain calcitonin gene-related peptide but rarely either substance P or fluoride-resistant acid phosphatase. However, the vast majority of pulpal nerve cells appear to have sizes and cytochemical characteristics which are not generally associated with nociceptive primary sensory neurons.

Acid Phosphatase↗
PubMed1989

Rapid degeneration of glial cells during early Wallerian degeneration in the neonatal kitten spinal cord.

Around 24 hours following neonatal lumbar dorsal root transections in kittens, the disintegration of myelinated axons in the lumbar dorsal column was accompanied by the appearance of numerous pyknotic profiles. These profiles were found to represent glial cells in various stages of degeneration. At earlier and later postlesion survival times similar profiles were rare or absent. It is suggested that acute changes in the physical and/or chemical properties of myelinated axons undergoing Wallerian degeneration during a particular developmental period is incompatible with survival of certain types of glial cells. These cells may be oligodendrocytes and/or so-called type II astrocytes.

Animals↗
PubMed1988

A horseradish peroxidase study of the central projections of primary trigeminal neurons innervating the hard palate in the cat.

The central projections of primary sensory neurons innervating the hard palate in the cat were studied by transganglionic transport of horseradish peroxidase conjugated to wheat germ agglutinin (WGA-HRP). Following injection of WGA-HRP in the incisive papilla terminal labeling was observed in all subdivisions of the sensory trigeminal nuclear complex. In the main sensory nucleus labeling was located in the dorsal part, especially in its most rostral portion. At the levels of nuclei oralis and interpolaris labeling was observed along the medial borders of the nuclei. In addition, at these levels distinct terminal labeling was located in patches within the trigeminal tract. In nucleus caudalis terminal labeling was confined to laminae I, II and V of the most rostral part of the nucleus. Some terminal labeling was observed also in the mid part of the solitary tract nucleus. After WGA-HRP injection in the posterior part of the hard palate a similar labeling pattern was found, but no labeling was observed in the solitary tract nucleus. The results in general indicate a relatively diffuse somatotopic organization of primary afferents innervating the palate. However, the somatotopic organization of palatine afferents within nucleus caudalis is at least partly consistent with the view that the central representation of the oral cavity is rotated 90 degrees to that of extraoral areas.

Animals↗
PubMed1988

Central distribution of trigeminal and upper cervical primary afferents in the rat studied by anterograde transport of horseradish peroxidase conjugated to wheat germ agglutinin.

Injections of WGA-HRP were made in the rat trigeminal ganglion and C1-3 dorsal root ganglia (DRGs) to study the central projection patterns and their relations to each other. Trigeminal ganglion injections resulted in heavy terminal labeling in all trigeminal sensory nuclei. Prominent labeling was also observed in the solitary tract nucleus and in the medial parts of the dorsal horn at C1-3 levels, but labeling could be followed caudally to the C7 segment. Contralateral trigeminal projections were found in the nucleus caudalis and in the dorsal horn at C1-3 levels. The C1 DRG was found to be inconstant in the rat. When it was present, small amounts of terminal labeling were found in the external cuneate nucleus (ECN) and the central cervical nucleus (CCN). No dorsal horn projections were seen from the C1 DRG. Injections in the C2 DRG resulted in heavy labeling in the ECN, nucleus X, CCN, and dorsal horn, where it was mainly located in lateral areas. Labeling could be followed caudally to the Th 7 segment. C2 DRG projections also appeared in the cuneate nucleus (Cun), in all the trigeminal sensory nuclei, and in the spinal, medial, and lateral vestibular nuclei. A small C2 DRG projection was observed in the ventral cochlear nucleus. C3 DRG injections resulted in heavy labeling in both medial middle and lateral parts of the dorsal horn, in the ECN, and in nucleus X, whereas the labeling in the CCN was somewhat weaker. Smaller projections were seen to trigeminal nuclei, Cun, and the column of Clarke. Comparisons of the central projection fields of trigeminal and upper cervical primary afferents indicated a somatotopic organization but with a certain degree of overlap.

Animals↗
PubMed1988

Changes in the central projection pattern of vibrissae innervating primary sensory neurons after peripheral nerve injury in the rat.

The central representation of a normal vibrissa nerve and the corresponding nerve after transection and regeneration of the infraorbital nerve has been studied by the use of transganglionic transport of horseradish peroxidase in the adult rat. The normal vibrissa nerve terminated in a well-defined area within nucleus caudalis and C1 dorsal horn. In contrast, the regenerated vibrissa nerve showed a widespread central termination pattern indicating a pronounced loss of somatotopic organization. These changes in somatotopic organization could contribute to an inability to correctly localize a sensory stimulus; this is a common clinical finding after peripheral nerve injury and regeneration.

Animals↗
PubMed1988

Changes in microglial cell numbers in the spinal cord dorsal horn following brachial plexus transection in the adult rat.

The effect of peripheral nerve transection on the size of the microglial cell population in cytoarchitecturally distinct regions of the spinal cord dorsal horn of rats was evaluated at selected intervals 2 through 35 days after unilateral brachial plexotomy. The identification of cells was verified by electron microscopic examination of a representative random sample of cells included in the counts. Microglial cell numbers were increased in laminae I, II as well as the arbitrarily defined deeper laminae 3.5 days after surgery. Although microglial cell numbers in laminae I were within normal range 35 days after axotomy, those of the more ventrally located laminae remained significantly greater than control values for the duration of the experimental period. These findings demonstrate that: 1) microglial cell proliferation in the dorsal horn is an early event in the central changes that are attendant to peripheral nerve injury 2) the time course of the response varies in cytoarchitecturally different regions.

Animals↗
PubMed1988

Carbonic anhydrase enzyme histochemistry of cranial nerve primary sensory afferent neurons in the rat.

Hanssons' enzyme histochemical method for the demonstration of carbonic anhydrase has been used to examine primary sensory neurons of cranial nerves in the rat (cochlear ganglion cells excluded). Numerous carbonic anhydrase positive neurons were present in the trigeminal and geniculate ganglia as well as in the mesencephalic trigeminal nucleus. A few carbonic anhydrase positive ganglion cells were found in the nodose ganglion, but none in the petrosal and vestibular ganglia. However, in the latter ganglia, satellite cells surrounding the neurons frequently showed staining for carbonic anhydrase.

Animals↗
PubMed1988

Sympathetic nerve fibers in peripheral sensory and motor nerves in the face of the rat.

Retrograde transport of horseradish peroxidase (HRP) has been used to investigate whether postganglionic neurons in the superior cervical ganglion send branches into various peripheral nerves in the rat. HRP was applied to the zygomatic branch of the facial nerve, the mental nerve, deep vibrissae nerves and to nerves in the tooth pulp. HRP-labeled neurons were consistently seen in the SCG in all types of experiments, except for the cases where HRP was applied to the tooth pulp.

Animals↗
PubMed1986

A quantitative study of the effects of neonatal capsaicin treatment and of subsequent peripheral nerve transection in the adult rat.

The effects of unilateral intercostal nerve transection have been studied in adult rats neonatally treated with capsaicin. Two rats were treated with capsaicin-free vehicle and served as controls. It is shown that capsaicin treatment leads to a dorsal root ganglion cell loss of about 43%, and about a 72% loss of unmyelinated dorsal root fibers. Myelinated dorsal root fibers remain unaffected. The cell size spectrum shows a 27% increase in median cell area in the capsaicin-treated rats, indicating a loss of preferentially smaller cells. A subsequent peripheral nerve transection resulted in a further cell loss of about 30% with no major change in cell size spectrum. The peripheral nerve transection also somewhat further reduces both the number of unmyelinated and myelinated dorsal root axons. The data indicate that neurons which die after a peripheral nerve transection belong to both the groups of cells, which are capsaicin-sensitive and capsaicin-resistant.

Animals↗
PubMed1986

Transganglionic degeneration in vibrissae innervating primary sensory neurons of the rat: a light and electron microscopic study.

Previous studies have shown that transection of peripheral branches of primary sensory neurons leads to light microscopical degeneration argyrophilia and ultrastructural changes in the central termination areas of these neurons. This type of degeneration has been termed transganglionic degeneration (TGD). In the present experiments TGD has been studied specifically in neurons innervating the rat vibrissae at the light and electron microscopic levels. Light microscopically, small amounts of degeneration argyrophilia are observed in the magnocellular zone of the trigeminal subnucleus caudalis at 8-14 days survival. At longer survival times there are substantial amounts of degeneration in this area. At the ultrastructural level the first signs of TGD are observed at 6 days survival, when some terminals show a small increase in electron density, loss of synaptic vesicles, and mitochondrial disintegration. Terminals showing a more advanced increase in electron density become common at 8 days survival, but few of them are still left at 14 days survival. Neurofilamentous terminals appear in small numbers 8-14 days postoperatively. Various forms of degeneration in myelinated axons are observed from 8 days survival and are common also at 80 days survival. Electron-dense axons are rather unfrequent, but more or less disrupted myelin sheaths containing disintegrated axoplasmic remnants and empty areas are common as well as extremely expanded myelin sheaths. Glial cells containing axonal and myelin debris are seen from 8 days survival and become a more common finding at longer survivals. A most striking finding 8-10 days postoperatively is a complex relationship between glial cells and less darkened terminals, indicating phagocytosis before reaching an entirely darkened state. The findings clearly show that peripheral nerve transection leads to severe central alterations in a population of mechanoreceptor neurons innervating the vibrissae of the adult rat.

Animals↗
PubMed1986

Cell loss in lumbar dorsal root ganglia and transganglionic degeneration after sciatic nerve resection in the rat.

The effects of sciatic nerve resection on lumbar dorsal root ganglion cells and their central branches have been studied in the adult rat. A quantitative analysis of the lumbar dorsal root ganglia indicated a 15-30% cell loss on the operated side. Argyrophilia indicating transganglionic degeneration was observed in Fink-Heimer stained sections from the lumbar spinal cord and the brainstem. The areas of degeneration argyrophilia were mainly located in the medial part of the ipsilateral L2-L6 dorsal horn laminae I-IV, the tract of Lissauer, the dorsal funiculus and the gracile nucleus. A few degenerating fibers could also be observed in the ipsilateral dorsal horn laminae V and VI, and in the ipsilateral ventral horn as well as in the contralateral dorsal horn and the gracile nucleus. The results confirm and extend previous findings at other levels and in other species. This suggests that cell loss and transganglionic degeneration may be general phenomena affecting a substantial proportion of primary sensory neurons following peripheral nerve injury.

Animals↗
PubMed1985

Transganglionic transport of wheat germ agglutinin-HRP and choleragenoid-HRP in rat trigeminal primary sensory neurons.

Horseradish peroxidase conjugates of either the lectin wheat germ agglutinin (WGA-HRP) or choleragenoid (B-HRP) have been shown to be sensitive neuroanatomical tracers. In the present study a comparison was made between these two conjugates as transganglionic tracers in trigeminal primary sensory neurons following injection into the rat mystacial vibrissae skin. Differences between the two tracers were observed in the labeling of cell bodies in the trigeminal ganglion. Injection of WGA-HRP resulted in labeling of predominantly small cell bodies, whereas B-HRP gave rise to labeling of somewhat larger cell bodies. By increasing the concentration of the injected WGA-HRP solution the number of labeled cells increased substantially, while a corresponding increase in the concentration of B-HRP resulted in a relatively small increase in the number of labeled cells. WGA-HRP injection resulted in labeling of primary afferents mainly in the substantia gelatinosa of the trigeminal subnucleus caudalis. When the concentration of the injected WGA-HRP solution was increased, labeling was also observed in the marginal and magnocellular zones. Following B-HRP injection, labeling was only observed in the magnocellular zone and innermost part of the substantia gelatinosa. This general pattern of labeling was the same when the concentration of the B-HRP solution was increased.

Animals↗
PubMed1985

The reaction of primary sensory neurons to peripheral nerve injury with particular emphasis on transganglionic changes.

This paper reviews light- and electron microscopic, histochemical and physiological evidence which demonstrate that peripheral nerve injury in mammals is followed by profound structural and functional changes in the central terminals of the affected primary sensory neurons. Available evidence indicates that at least some of these so-called transganglionic changes are the result of ganglion cell degeneration and death, although other mechanisms are probably in effect as well. Existing data suggest that this ganglion cell death does not effect all types of ganglion cells equally, but do not permit a clearcut answer to the question of which kinds of ganglion cells are affected more than others. Results from studies with microtubule inhibitors and antibodies to nerve growth factor are compatible with the notion that depletion of retrogradely transported trophic factors is involved in the production of certain transganglionic changes. This issue needs further examination, however. Physiological studies indicate marked alterations in certain primary afferent synaptic connections after peripheral nerve lesions. So far, these changes have not been satisfactorily correlated with the structural changes induced by similar lesions. Further studies on the structural and functional response of primary sensory neurons to peripheral nerve injury are likely to contribute to the understanding of the frequent failure to regain normal sensory functions after peripheral nerve lesions in man, as well as of the basic aspects of lesion-induced changes in general in the peripheral and central nervous system.

Acid Phosphatase↗
PubMed1984

Evidence for a sympathetic component in motor branches of the facial nerve: a horseradish peroxidase study in the cat.

The retrograde transport of horseradish peroxidase (HRP) was used to examine the location of sympathetic ganglion cells with axons in facial motor branches of the cat. Large numbers of HRP-labeled neurons were observed in the rostro-anterior part of the superior cervical ganglion. In addition, some labeled neurons were found in the cervical sympathetic trunk, the accessory cervical, middle cervical and stellate ganglia.

Adrenergic Fibers↗
PubMed1984

An HRP study of the central course of sensory intermediate and vagal fibers in peripheral facial nerve branches in the cat.

Previous studies have shown that sensory fibers of intermediate and vagal nerve origin are present in facial nerve branches to the mimetic muscles in the cat. In the present study the central course of these fibers has been examined by transganglionic transport of horseradish peroxidase (HRP). In some of these experiments the facial nerve proper was transected central to the site of HRP application. In this way, the central course of the vagal fibers could be studied separately. For comparison HRP-conjugated wheat germ agglutinin was injected into the geniculate ganglion, revealing the central course of the entire afferent component of the intermediate nerve. The results show that labeled sensory intermediate nerve fibers, at their level of entrance in the brainstem, form a tract at the dorsal margin of the spinal trigeminal tract (5T). While some fibers ascend from this level to terminate in the main sensory trigeminal nucleus, and a few fibers terminate in the rostral part of the solitary tract nucleus, the majority take a descending course. The main site of termination for these descending fibers is in the medial part of the C2 dorsal horn. Terminal labeling is also seen in the ventrolateral part of the cuneate nucleus (CUN) and in a small area of gray substance between CUN and trigeminal nucleus caudalis. After entering the brainstem some sensory vagal fibers project to the trigeminal nucleus interpolaris and to an interstitial nucleus within the 5T, but the larger part joins the descending tract of intermediate nerve fibers. These descending vagal fibers have a terminal distribution pattern similar to the intermediate nerve fibers.

Afferent Pathways↗
PubMed1984

Cerebral palsy and perinatal deaths in geographically defined populations with different perinatal services.

The number of perinatal deaths and of children with cerebral palsy among 23,039 total births between 1973 and 1978 in one Swedish county were examined by comparing two populations which differed by the presence or absence of a neonatal ward (special care baby unit) in the maternity hospital for the district. No support was found for the assumption that lower perinatal mortality in the region without a neonatal ward would be at the cost of an increased number with cerebral palsy. Between the two three-year periods there was a highly significant decrease in perinatal mortality in the sample without a neonatal ward. When perinatal deaths and cerebral palsy were considered together the decline remained highly significant. The corresponding change in the sample with a neonatal ward was smaller and non-significant.

Ataxia↗