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
    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 ...
  • 2
    ISSN: 1432-0533
    Keywords: Trauma ; Spinal cord injury ; Edema ; Serotonin ; p-CPA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The possibility that serotonin can modify the early pathological sequences occurring in spinal cord trauma was investigated in a rat model. To that end we took advantage of the possibility of influencing serotonin pharmacologically by treating animals with a serotonin synthesis inhibitor, p-chlorophenylalanine (p-CPA) before the production of the injury and compared the results with injured, untreated controls. A unilateral incision was made into the dorsal horn of the lower thoracic cord (about 2.5 mm deep, 4.5 mm long) and the trauma. The injured region from untreated animals showed macroscopically at that time a pronounced swelling and the water content had increased by 3.5% as compared to intact controls. The segments rostral and caudal to the lesion also exhibited a profound increase in water content. Light microscopy revealed a significant expansion of the spinal cord as compared to controls. The swelling was most pronounced in the gray matter on the injured side. Electron microscopy showed distorted neurons, swollen astrocytes and extracellular edema in the gray matter in and around the primary lesion. There was also a sponginess in the surrounding white matter with disruption of myelin, collapsed axons and widened periaxonal spaces. Pretreatment of the rats with p-CPA significantly reduced the swelling of the injured spinal cord and there was no visible expansion. The ipsilateral edema in the central gray matter was considerable less pronounced as compared to that in untreated animals. The increase in water content was less than 1% in these animals. The neuronal and glial cell changes were also markedly reduced in the drugtreated rats. The disruption of myelin and the vacuolation of the gray matter were much less severe. Our results show that p-CPA can markedly modify the edema and the cellular changes occurring in the traumatic spinal injury and indicate that serotonin is somehow involved in the production of the early, and thus important, pathological events.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 79 (1990), S. 595-603 
    ISSN: 1432-0533
    Keywords: Trauma ; Spinal cord injury ; Microvascular permeability ; Serotonin ; p-Chlorophenylalanine (p-CPA)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The possibility that serotonin can take part in the initiation of the increased microvascular permeability occurring in a spinal cord trauma was investigated in a rat model with 131I-sodium and lanthanum as tracers. We influenced the serotonin content in the tissue pharmacologically by treating animals with a serotonin synthesis inhibitor, p-chlorophenylalanine (p-CPA), before the production of the injury and compared the results with injured, untreated controls. A small incision was made in the dorsal horn of the lower thoracic cord. It caused a progressive extravasation of 131I-sodium in the damaged segment, measured after 1,2 and 5 h. Rostral and caudal segments also showed a significant but lower accumulation of 131I-sodium. Lanthanum added to the fixative was used as an ionic tracer detectable by electron microscopy. The endothelial cells of microvessels removed from the perifocal region after 5 h showed a marked increase in the number of lanthanum-filled vesicles. Many endothelial cells had a diffuse penetration of the tracer into the cytoplasm and the basement membrane. However, the tight junctions usually remained closed to lanthanum. Pretreatment with p-CPA markedly reduced the extravasation of 131I-sodium measured at 5 h in the traumatized cord. At the cellular level, the endothelial vesicles filled with lanthanum approached the condition of uninjured animals. The diffuse infiltration of lanthanum into endothelial cells and its spread into the basement membrane of the vascular wall were usually absent. Our results indicate that serotonin plays a role in the initiation of the increased microvascular permeability which occurs in spinal cord injuries.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    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 ...
  • 5
    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 ...
  • 6
    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...