Linked Life Data

18555615

Source:http://linkedlifedata.com/resource/pubmed/id/18555615

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2008-7-7
pubmed:abstractText
Long term facilitation (LTF) of C-fiber-evoked firing of wide dynamic range neurons in the spinal dorsal horn in response to conditioning stimulation (CS) of afferent fibers is a widely studied cellular model of spinal nociceptive sensitization. Although 100 Hz CS of primary afferent fibers is commonly used to induce spinal cord LTF, this frequency exceeds the physiological firing range. Here, we examined the effects of electrical stimulation of the sciatic nerve within the physiological frequency range on the magnitude and stability of the C-fiber-evoked responses of wide dynamic range neurons and the expression of immediate early genes (c-fos, zif268, and Arc) in anesthetized rats. Stimulation frequencies of 3, 30 and 100 Hz all induced facilitation of similar magnitude as recorded at 1 h post-CS. Strikingly, however, 3 Hz-induced potentiation of the C-fiber responses was decremental, whereas both 30 and 100 Hz stimulation resulted in stable, non-decremental facilitation over 3 h of recording. The number of dorsal horn neurons expressing c-fos, but not zif268 or Arc, was significantly elevated after 3 Hz CS and increased proportionally with stimulation rate. In contrast, a stable LTF of C-fiber responses was obtained at 30 and 100 Hz CS, and at these frequencies there was a sharp increase in zif268 expression and appearance of Arc-positive neurons. The results show that response facilitation can be induced by stimulation frequencies in the physiological range (3 and 30 Hz). Three hertz stimulation induced the early phase of LTF, but the responses were decremental. Arc and zif268, two genes previously coupled to LTP of synaptic transmission in the adult brain, are upregulated at the same frequencies that give stable LTF (30 and 100 Hz). This frequency-dependence is important for understanding how the afferent firing pattern affects neuronal plasticity and nociception in the spinal dorsal horn.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1873-7544
pubmed:author
pubmed:issnType
Electronic
pubmed:day
17
pubmed:volume
154
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1568-75
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Stability of long term facilitation and expression of zif268 and Arc in the spinal cord dorsal horn is modulated by conditioning stimulation within the physiological frequency range of primary afferent fibers.
pubmed:affiliation
Department of Biomedicine, University of Bergen, Bergen, Norway.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't