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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2008-8-21
pubmed:abstractText
During ageing process, multiple changes occur on nervous tissue composed of cells and extracellular matrix. Changes on nervous tissues are usually known as degenerative changes on axon structure and connective tissue covering the nerve such as a decrease in the number of fibre or general structural changes. For this purpose, we have studied age-dependent ultrastructural changes in the rat oculomotor nerve with electron microscopy and also demonstrated collagen structure of the neural sheaths with immunohistochemical techniques. This study was conducted in Gazi University Faculty of Medicine, Department of Anatomy with a total of nine Wistar albino rats. We observed strong collagen type I immunoreactivity in endoneurium and slight to moderate reactivity in fibroblast cytoplasm in 3-month- and 12-month-old groups and mild reactivity in 24-month-old group. Collagen type IV immunoreactivity was stronger in endoneurium and perineurium in the 3-month- and 12-month-old groups compared with collagen type I and fibroblast cytoplasm showed a very strong reactivity. On the other hand, in the 24-month-old group, there was slight reactivity in endoneurium and a strong reactivity in perineurium. NGF staining showed moderate to strong reactivity on Schwann cells of the 3-month-old group. The immunoreactivity decreased in the 12-month- and 24-month-old groups. In the 3-month-old rat group, Schwann cell cytoplasm, mitochondrial structure and neurofilaments were normal. In the 12-month-old group, there were no changes in organelle distribution, mitochondrial structure and neurofilaments, but there was an increase in the connective tissue. An inconsiderable number of degenerated myelinated nerves were observed. We detected an important decrease in the collagen type I immunoreactivity, which could suggest that the endoneurium, perineurium and epineurium are less resistant to the age-related collagen loss and that the peripheral nerve is protected by a weaker barrier in the old group. The collagen type IV immunoreactivity was significantly decreased with age. NGF synthesis decreases with age because of Schwann cell structural degeneration or for different reasons. Thus, this could explain the diminished capacity of regeneration and damage of the myelination of the peripheral nerve.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1439-0264
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
279-84
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Age-related immunohistochemical and ultrastructural changes in rat oculomotor nerve.
pubmed:affiliation
Department of Anatomy, Faculty of Medicine, University of Gazi, Ankara, Turkey. meltemb@gazi.edu.tr
pubmed:publicationType
Journal Article