Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2003-12-25
pubmed:abstractText
In the spinal cord, nitric oxide (NO) pathway is involved in pain and hyperalgesia, and nitric oxide synthase (NOS) expression and NO production are upregulated following several noxious and lesion stimuli. However, the mechanism of the increases is yet not well understood. The present study was designed to address the question of whether substance P (SP) released in the spinal cord enhances NOS expression and NO production of the spinal cord in rats. [Sar(9), Met(O2)(11)]-substance P (Sar-SP), a neurokinin-1 (NK-1) receptor agonist, was administered by intrathecal injection via L(5)-L(6) intervertebral space to induce nociception. The pain threshold was determined by hot water induced tail flick test. NOS expression of the L(5) segment of the spinal cord was determined using NADPH-d histochemical staining. NO production of the lumbar enlargement of the spinal cord was determined by assaying NO3(-) and NO2(-), the end product of NO metabolism, using the method of aqua fortis reduction. We found that (1) intrathecal injection of Sar-SP (6.5 nmol) elicited a characteristic, caudally directed, nociceptive behavioural response consisting of intense biting, licking and scratching episodes. Tail flick test showed decrease in pain threshold. (2) following the behavioural responses, the NOS expression level, including the number and the staining density of the NADPH-d reactive cells, increased in the superficial portion of the dorsal horn (Laminae I-II) and the grey matter surrounding the central canal (LaminaX) of the L(5) segment of the spinal cord after the Sar-SP intrathecal injection. At the same time, NO production in the enlargement of the spinal cord increased. (3) The decreased pain threshold and the increases in NOS expression and NO production could be substantially inhibited by intrathecal injection of [[D-Arg(1), D-Trp(7,9), Leu(11)]-substance P] (spantide) (5 microg), a non-selective antagonist of NK-1 receptor, 5 min prior to the Sar-SP injection. It might be concluded that the release of SP resulted from nociceptive afferents increased NOS expression and NO production of the rat spinal cord.
pubmed:language
chi
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0371-0874
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
677-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
[Intrathecal injection of Sar9, Met(O2)11-substance P, neurokinin-1 receptor agonist, increases nitric oxide synthase expression and nitric oxide production in the rat spinal cord].
pubmed:affiliation
Department of Pathophysiology, Institute of Basic Medicine, Hebei Medical University, Shijiazhuang, 050017.
pubmed:publicationType
Journal Article, English Abstract, Research Support, Non-U.S. Gov't