Linked Life Data

9027875

Source:http://linkedlifedata.com/resource/pubmed/id/9027875

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1997-4-29
pubmed:abstractText
While it is well established that nerve growth factor is growth promoting for sensory neurons in culture, it is unclear whether it serves such a function in vivo. In fact, our previous studies led to the hypothesis that nerve growth factor could actually impair axonal regeneration by reducing the neuronal cell body response to injury. In the present study, the consequence of continuous intrathecal infusion of nerve growth factor on regeneration of sensory neurons was examined in rats given a bilateral sciatic nerve crush. Rats received nerve growth factor (125 ng/h) as a continuous infusion into the subarachnoid space of the lumbar spinal cord via an osmotic minipump (Alzet); controls received cytochrome C. At seven or 10 days, the pump was removed and L4 or L5 dorsal root ganglion exposed and injected with 50 microCi of (3H)leucine. Animals were killed 24 h later, the sciatic nerves removed, cut into 3 mm segments and the radioactivity in each segment determined by liquid scintillation spectrophotometry. Maximal regeneration distances (determined from the front of the resultant transport curves) were similarly reduced (by approximately 6 mm) in nerve growth factor-infused compared to cytochrome C-infused rats. Thus, regeneration rates (determined between eight and 11 days) were unaltered by nerve growth factor infusion; regeneration rates from cytochrome C-infused and nerve growth factor-infused animals were 2.8 mm/day and 3.1 mm/day, respectively. However, nerve growth factor significantly (P < 0.005) increased the delay to onset for regeneration by two days. Taken together, the present study demonstrates that nerve growth factor delays the onset of regeneration without affecting the rate of regeneration. The results implicate the involvement of at least two signals in the regulation of axonal regeneration in dorsal root ganglion neurons. It is suggested that the loss of nerve growth factor serves as an early, induction signal regulating the onset of regeneration and that a second, unidentified signal independently serves to maintain regeneration.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0306-4522
pubmed:author
pubmed:issnType
Print
pubmed:volume
76
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1153-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Axonal regeneration of sensory nerves is delayed by continuous intrathecal infusion of nerve growth factor.
pubmed:affiliation
Center for Research on Occupational and Environmental Toxicology, Oregon Health Sciences University, Portland 97201, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.