Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1995-12-13
pubmed:abstractText
The effects of tumor necrosis factor-alpha (TNF-alpha) on the production of the vasoactive substances nitric oxide (NO) and endothelin-1 (ET-1) were investigated in cerebrovascular cells in culture. Bovine cerebral endothelial cells (BCEC) stained positively for NADPH-diaphorase/NO synthase activity and spontaneously produced nitrite, a stable NO oxidation product, which accumulated in the culture medium in a linear way for 48 h. Low concentrations of TNF-alpha (0.5-2 ng/ml) significantly enhanced nitrite production after a 24-h incubation. Higher concentrations or longer exposure times resulted in a cytotoxic effect that altered cell morphology, released lactate dehydrogenase (LDH) to the culture medium, and reduced the protein content. Dexamethasone, but not the NO synthase inhibitor N-iminoethyl-L-ornithine (L-NIO), prevented the cytotoxic effect of TNF-alpha in BCEC. TNF-alpha also significantly enhanced nitrite production in bovine cerebral smooth muscle cells (BCSMC). The enhancement was detected at all times between 8 and 72 h and at all concentrations tested (2-100 ng/ml). Signs of cytotoxicity were not observed in BCSMC after incubation with TNF-alpha. ET-1 was constitutively secreted by BCEC. The production of ET-1 was stimulated by thrombin. TNF-alpha enhanced the release of ET-1 in BCEC, and this enhancement was not modified by the simultaneous addition of interferon-gamma (IFN-gamma). BCSMC did not produce ET-1, either spontaneously or in the presence of TNF-alpha, IFN-gamma, or of both together.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0271-678X
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
920-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Effects of TNF-alpha on the production of vasoactive substances by cerebral endothelial and smooth muscle cells in culture.
pubmed:affiliation
Department of Physiology, Faculty of Medicine, Universidad Autónoma de Madrid, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't