Linked Life Data

12736384

Source:http://linkedlifedata.com/resource/pubmed/id/12736384

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2003-7-25
pubmed:abstractText
After birth, constriction of the full-term ductus arteriosus produces ischemic hypoxia, caspase activation, DNA fragmentation (>70% of cell nuclei are positive by the terminal deoxynucleotidyl transferase nick-end labeling [TUNEL] technique), and permanent ductus closure. In contrast, the preterm ductus frequently fails to develop these changes. We used the TUNEL technique to examine rings of fetal ductus arteriosus (incubated for 24 h at different oxygen and glucose concentrations) to determine the roles of 1) constriction and shortening, 2) hypoxia, and 3) hypoglycemia in producing cell death. Under controlled conditions, late-gestation ductus rings had a low rate of TUNEL-positive staining (0.6 +/- 0.9%) that did not change during muscle shortening. Although hypoxia (6.9 +/- 3.5%) and hypoglycemia (2.4 +/- 1.9%) increased the incidence of TUNEL-positive staining, only the combination of hypoxia-plus-hypoglycemia increased the incidence to the range found in vivo (83 +/- 9.5%). The combination of hypoxia-plus-hypoglycemia was associated with an oligonucleosomal pattern of DNA fragmentation. Under the same experimental conditions, the preterm ductus was capable of developing a similar degree of TUNEL-positive staining as found at term. Although caspase-3 and caspase-7 were activated in rings exposed to hypoxia-plus-hypoglycemia, a nonselective caspase inhibitor, Z-VAD.FMK (which inhibited caspase-3 and caspase-7 cleavage in the rings), did not diminish the degree of TUNEL-positive staining. We hypothesize that the preterm ductus is capable of developing an extensive degree of cell death, if it can develop the same degree of hypoxia and hypoglycemia found in the full-term newborn ductus. We also hypothesize that cell death in the ductus wall may involve pathways that are not dependent on caspase-3 or -7 activation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0031-3998
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
204-11
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Effects of hypoxia, hypoglycemia, and muscle shortening on cell death in the sheep ductus arteriosus.
pubmed:affiliation
Box 0544, HSE 1492, University of California San Francisco, 513 Parnassus Ave., San Francisco, CA 94143-0544, U.S.A.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't