Linked Life Data

9295147

Source:http://linkedlifedata.com/resource/pubmed/id/9295147

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-10-23
pubmed:abstractText
We have quantified the number and size of myelinated fibers of the ventral and dorsal roots of selected segments that innervate the forelimbs (C8) and hindlimbs (L4) in the developing opossum, Monodelphis domestica. The gray opossum was chosen because it is born very immature and its somatomotor development occurs almost entirely postnatally. After aldehyde fixation, osmium postfixation, and resin embedding, the roots were cut transversely (1.5 pm), stained with toluidine blue, and observed and photographed by using light microscopy. The counts and measurements were made with a digitizing table. Myelination of the C8 and L4 roots begins during the second week of life and occurs according to two gradients: rostrocaudal and ventrodorsal. The number of myelinated fibers in these roots increased over approximately 7 weeks after which an excess, compared with their adult value, was recorded during the following weeks in three of the four roots. The supernumerary myelinated fibers are presumed to be collaterals. The fibers increased in diameter until at least 98 days. The classification according to size for the ventral roots (alpha and gamma) became evident in the fourth week, but that in types I, II, and III for the dorsal roots was never clear. There was no significant difference in the number and size distribution of myelinated fibers between sexes until late in development. The fibers innervating the limbs thus become myelinated postnatally in the opossum, a process that occurs over a protracted period and that continues after sensorimotor reflexes and locomotion appear adult-like.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9967
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
386
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
203-16
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Myelination of the ventral and dorsal roots of the C8 and L4 segments of the spinal cord at different stages of development in the gray opossum, Monodelphis domestica.
pubmed:affiliation
Département de Sciences Biologiques, Université de Montréal, Quebec, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't