Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 80 (1990), S. 12-17 
    ISSN: 1432-0533
    Keywords: Serotonin (5-hydroxytryptamine, 5-HT) ; Spinal cord trauma ; Ventral horn ; p-Chlorophenyl alanine ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The possibility that serotonin (5-hydroxytryptamine, 5-HT) is involved in the early tissue reactions occurring in spinal cord trauma was examined in a rat model using an immunocytochemical technique. The injury was made in the form of a 5-mm long and 2.5-mm wide lesion of the right dorsal horn at the level of T10–11. Injured rats, pretreated with the 5-HT synthesis blocking agent, p-chlorophenyl alanine (p-CPA) were compared with untreated injured controls and the animals were allowed to survive for 5 h. The distribution of 5-HT was examined in proximal and distal cross-sections of the cord, located 2 and 5 mm away from the injury. Normal rats showed immunoreactive material in nerve cell processes and in a few nerve cell bodies of the ventral horns. The trauma to the spinal cord caused a marked increase in 5-HT immunoreactivity in the segments located 2 mm proximal and distal to the injury, particularly in the ipsilateral ventral horn. The segment located 5 mm distal to the lesion showed a similar increase in immunoreactivity but it was apparently less pronounced in the corresponding proximal segment. Treatment with p-CPA markedly reduced the trauma-induced increase in 5-HT immunoreactivity in all the segments. These immunohistochemical findings were in line with the changes in the contents of 5-HT measured biochemically in corresponding spinal cord segments. At the onset of the trauma to the spinal cord 5-HT is thus present in the tissue, mainly in the form of 5-HT-containing nerve cell processes. Biochemical determinations also revealed that there is an increased amount of 5-HT in the traumatized spinal cord. The present study indicates that this is at least partly due to an increased amount of 5-HT in neurons and nerve cell processes of the perifocal region. The pathophysiollogical significance of the observed 5-HT-reaction in spinal cord injury is not known in all its details. However, 5-HT might be implicated in such tissue reaction, such as increased microvascular permea bility and edema formation occurring in the early period after trauma.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-0533
    Keywords: Spinal cord trauma ; Glial fibrillary acidic protein ; Serotonin ; p-Chlorophenylalanine ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The possibility that serotonin may influence the early response of astrocytes around a spinal cord trauma was investigated in a rat model by making a unilateral incision into the right dorsal horn of the T10-11 segments. One group of rats received a serotonin synthesis inhibitor, p-chlorophenylalanine (p-CPA) before injury in doses which cause a depletion of serotonin in the cord. Another group of traumatised rats did not receive p-CPA. All animals were allowed to survive for 5 h. Samples for immunohistochemistry were taken from the T9, T10-11 and T12 segments of the cord. Paraffin sections were immunostained for glial fibrillary acidic protein (GFAP) using monoclonal antibodies and avidin-biotin complex technique. Trauma to the cord resulted in a marked increase of GFAP immunoreactivity in all the investigated segments, particularly in the ipsilateral side. Pretreatment with p-CPA markedly reduced the GFAP response. This drug did not by itself influence the GFAP immunoreactivity of the cord of untraumatised rats. Our results show that trauma to the spinal cord induces a rapid enhancement of GFAP immunoreactivity in the cord which is present even far away from the primary lesion. This response can be prevented by pretreatment with the serotonin synthesis inhibitor, p-CPA. The results indicate that serotonin influences the increase of GFAP immunoreactivity following spinal cord injury either directly or indirectly, for instance by its microvascular reactions.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1438-2199
    Keywords: Nitric oxide ; Spinal cord evoked potentials ; Edema ; Cell changes ; p-CPA ; Diazepam ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The possibility that nitric oxide is somehow involved in the early bioelectrical disturbances following spinal cord injury in relation to the later pathophysiology of the spinal cord was examined in a rat model of spinal cord trauma. A focal trauma to the rat spinal cord was produced by an incision of the right dorsal horn of the T 10–11 segments under urethane anaesthesia. The spinal cord evoked potentials (SCEP) were recorded using epidural electrodes placed over the T9 and T12 segments of the cord following supramaximal stimulation of the right tibial and sural nerves in the hind leg. Trauma to the spinal cord significantly attenuated the SCEP amplitude (about 60%) immediately after injury which persisted up to 1h. However, a significant increase in SCEP latency was seen at the end of 5h after trauma. These spinal cord segments exhibited profound upregulation of neuronal nitric oxide synthase (NOS) immunoreactivity, and the development of edema and cell injury. Pretreatment with a serotonin synthesis inhibitor drug p-chlorophenylalanine (p-CPA) or an anxiolytic drug diazepam significantly attenuated the decrease in SCEP amplitude, upregulation of NOS, edema and cell injury. On the other hand, no significant reduction in SCEP amplitude, NOS immunolabelling, edema or cell changes were seen after injury in rats pretreated with L-NAME. These observations suggest that nitric oxide is somehow involved in the early disturbances of SCEP and contribute to the later pathophysiology of spinal cord injury.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1438-2199
    Keywords: Brain derived neurotrophic factor ; Insulin like growth factor-1 ; Nitric oxide ; Spinal cord injury ; Edema ; Cell injury ; Blood-spinal cord barrier ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The possibility that brain derived neurotrophic factor (BDNF) and insulin like growth factor-1 (IGF) induced neuroprotectivn is influenced by mechanisms involving nitric oxide was examined in a rat model of focal spinal cord injury. BDNF or IGF-I (0.1 μg/10 [1 in phosphate buffer saline) was applied topically 30 min before injury on the exposed spinal cord followed by repeated doses of growth factors immediately before and 30 min after injury. Thereafter application of BDNF or IGF was carried out at every 1 h interval until sacrifice. Five hours after injury, the tissue pieces from the T9 segment were processed for nNOS immunostaining, edema and cell injury. Untreated injured rats showed a profound upregulation of nNOS which was most pronounced in the nerve cells of the ipsilateral side. A marked increase in the blood-spinal cord barrier (BSCB) permeability to125I-albumin, water content and cell injury in these perifocal segments was also found. Pretreatment with BDNF and IGF significantly reduced the upregulation of nNOS in the spinal cord. This effect of the growth factors was most pronounced in the contralateral side. Rats treated with these neurotrophic factors showed much less signs of BSCB damage, edema and cell injury. These results suggest that BDNF and IGF pretreatment is neuroprotective in spinal cord injury and that these neurotrophic factors have the capacity to down regulate nNOS expression following trauma to the spinal cord. Our data provide new experimental evidences which suggest that BDNF and IGF may exert their potential neuroprotective effects probably via regulation of NOS activity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1438-2199
    Keywords: Keywords: Amino acids ; Spinal cord injury ; Heme oxygenase ; Heat shock protein ; Carbon monoxide ; Growth factors ; BDNF ; IGF-1 ; Immunohistochemistry ; Cell injury ; Spinal cord edema
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary. The influence of brain derived neurotrophic factor (BDNF) or insulin like growth factor-1 (IGF-1) on spinal cord trauma induced carbon monoxide (CO) production and cellular stress response was examined using immunostaining of the constitutive isoform of the hemeoxygenase (HO-2) enzyme and the heat shock protein (HSP 72 kD) expression in a rat model. Subjection of rats to a 5 h spinal trauma inflicted by an incision into the right dorsal horn at T10–11 segment markedly upregulated the HO-2 and HSP expression in the adjacent spinal cord segments (T9 and T12). Pretreatment with BDNF or IGF-1 significantly attenuated the trauma induced HSP expression. The upregulation of HO-2 was also considerably reduced. These results show that BDNF and IGF-1 attenuate cellular stress response and production of CO following spinal cord injury which seems to be the key factors in neurotrophins induced neuroprotection.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1438-2199
    Keywords: Keywords: Amino acids ; Nerve lesion ; Neuropathic pain ; Heme oxygenase ; Carbon monoxide ; Cell injury ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary. The influence of carbon monoxide (CO) on chronic spinal nerve lesion induced spinal cord neurodegeneration was examined using immunohistochemical expression of the constitutive isoform of its synthesising enzyme, hemeoxygenase-2 (HO-2) in a rat model. Spinal nerve lesion at L-5 and L-6 level was produced according to the Chung model of neuropathic pain and rats were allowed to survive for 8 weeks. Sham operated rats, in which the spinal nerves were exposed but not ligated, served as controls. Ligation of spinal nerves in rats resulted in an upregulation of HO-2 expression which was most pronounced in the ipsilateral gray matter of the spinal cord compared to the contralateral side. In these rats, morphological investigations showed distorted neurons, membrane disruption, synaptic damage and myelin vesiculation. Sham operated rats did not show an upregulation of HO-2 expression and the structural changes in the spinal cord were absent. These observations strongly suggest that spinal nerve lesion is associated with an increased production of CO which is somehow contributing to the neurodegenerative changes in the spinal cord, not reported earlier.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 49 (1990), S. 209-214 
    ISSN: 1573-5060
    Keywords: Triticum aestivum ; wheat ; Agropyron spp. ; embryo rescue ; wide crosses ; crossability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Soft winter wheat lines were crossed with Agropyron intermedium, A. elongatum and A. trichophorum using pollen from single plants of Agropyron spp. to pollinate wheat spikes. Not only species but also individual plants within varieties of Agropyron species differed in percent seed set with a wheat genotype. In two arrays of crosses between two phenotypically different plants of A. elongatum and nine wheat lines, one Agropyron plant gave higher seed set (overall=27.1%) than the other (overall=3.7%). The differences were significant in seven of the nine cross combinations. Results are consistent with the hypothesis that these two plants differ in their crossability as pollen parents with wheat, and suggest the possibility of occurrence of crossability genes in wheatgrasses. The success rate of hybrid embryo rescue was higher (87.5%) with cold treatment (4°C) than without cold treatment (75.0%) of excised embryos on culture media. Results underscore the significance of genotype of the alien species for crossing with low crossable wheats, and of the physical factors for improving embryo rescue in wide crosses.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Euphytica 82 (1995), S. 43-64 
    ISSN: 1573-5060
    Keywords: wide cross ; wide hybridization ; interspecific cross ; Triticeae ; Agropyron complex ; wheatgrasses ; Triticum ; wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Wide crosses in wheat are reviewed in relation to various factors that facilitate wide crossing to show that wide crosses can be as wide as one can make them. Included in this review is a particular reference to wheat-wheatgrass (Agropyron complex) crosses and an update on wide crosses of wheat with various genera of Agropyron complex. Hybrid seed set is too variable to predict whether a wide hybrid, where no seed was obtained in one attempt, will not be possible. High crossability genes seem to facilitate not only fertilization but also seed development, enabling embryo rescue. Variability for crossability occurs not only in wheat but also in alien species. Contrary to conventional thinking, several wide hybrids with wheat can be produced when species with lower chromosome numbers are used as female parents. Pre-and post-fertilization barriers to wide crosses do not appear to be equally strong, and can be overcome by the development and application of various technologies. Considering these aspects of wide hybridization, and based on recent successes in producing previously unsuccessful and very wide hybrids, it is concluded that how wide cross between plant species can be made is an open question and that many new and wider hybrids can be produced in future.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Plant cell, tissue and organ culture 24 (1991), S. 233-236 
    ISSN: 1573-5044
    Keywords: anther culture ; cultivars ; Triticum aestivum ; wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Twenty-two cultivars and lines of winter and spring wheat (Triticum aestivum L.) were studied, most for the first time, for their anther culture response. The response was genotype dependent. Plants grown in the field gave higher callus induction frequency than those grown in the greenhouse and the controlled environment chamber. Donor plants grown in a season of low drought stress as compared to a season of severe drought stress resulted in a higher frequency of callus induction. Spherical microcalli were observed in two wheat genotypes in some of only those anthers that were placed with only one loculus in contact with the medium. Wheat lines that were more responsive to anther culture were identified.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...