Linked Life Data

11063983

Source:http://linkedlifedata.com/resource/pubmed/id/11063983

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-12-11
pubmed:abstractText
Nitric oxide (NO) is a major non-adrenergic, non-cholinergic (NANC) inhibitory neurotransmitter in the gastrointestinal tract. NO released from the myenteric plexus enhances colonic transit and facilitates propulsion of the colonic contents by mediating descending relaxation. Although it has been suggested that colonic transit delays with aging, the mechanism of delayed colonic transit in aging remains unclear. We hypothesized that advanced age is associated with decreased expression of neuronal NO synthase (nNOS) and concomitant reduction in synthesis of NO in the rat colon. We studied nNOS mRNA expression, nNOS-immunohistochemistry, nNOS-immunoblotting and NOS catalytic activity in the mid-colon obtained from young (age 4-8 months) and aged (age 22-28 months) Fisher (F344xBN)F1 rats. Western blot analysis of PGP 9.5, a generic neuronal marker, of the colonic tissues were employed to study whether the total number of neurons of the myenteric plexus is reduced with aging. The number of nNOS-immunoreactive cells and nNOS synthesis in the colonic myenteric plexus were significantly reduced in aged rats. In contrast, expression of PGP 9.5 in colonic tissues was not affected in aged rats. Northern blot analysis demonstrated that the expression of neuronal nNOS mRNA was significantly reduced in the colonic tissues in aged rats. Basal and veratridine-induced release of L-[(3)H]citrulline were significantly decreased in colonic tissues from aged rats, compared to young rats. It is suggested that advanced age is associated with diminished gene expression of nNOS, nNOS synthesis and catalytic activity of NOS. This may explain the mechanism of delayed colonic transit observed in advanced age.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
883
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15-21
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Decreased expression of nitric oxide synthase in the colonic myenteric plexus of aged rats.
pubmed:affiliation
Department of Internal Medicine, The University of Michigan Medical Center, 6520 MSRB I, Box 0682, Ann Arbor, MI 48109, USA. ttakahas@duke.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't