Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-2-15
pubmed:abstractText
Male rats aged 3 months, 12 months and 20 months were subjected to breathing 8% oxygen for 6 hours. Lung preproadrenomedullin (AM) messenger RNA (mRNA) levels were measured by solution hybridization-RNase protection assay while AM was measured by radioimmunoassay. The binding of hypoxia-inducible factor-1alpha (HIF-1alpha) to DNA was determined by electrophoretic mobility shift. There was an age-related increase in basal levels of preproAM mRNA and AM and of the binding of hypoxia-inducible factor (HIF) to DNA. Upon hypoxic stimulation, HIF binding to DNA increased in the young and middle-aged rats, but not in the old rats. AM gene expression increased in response to hypoxia in rats of all ages, but the increase was much less in the old rats. AM peptide levels in the lung decreased with age in hypoxia. In a separate experiment, male rats aged 3 months and 20 months were subjected to hypoxia as described above. PreproAM, calcitonin receptor-like receptor (CRLR), receptor activity modifying protein (RAMP) mRNA, HIF-1 and peptidyl-glycine-amidating monooxygenase (PAM) mRNA levels were measured by reverse transcription-polymerase chain reaction. All except PAM showed a decrease in basal levels and a diminished response to hypoxia in the old rats. Polysome profiling demonstrated decreases in the percentages of translatable preproAM mRNA in response to hypoxia, with a greater decrease in the old than the young rats. It is concluded that an age-dependent decrease in the hypoxic response of the AM system in the lung was associated with high basal levels of HIF activity and AM expression in the old rats, and a lower proportion of translatable preproAM mRNA in the old rats in response to hypoxia. Thus, the HIF-AM pathway may be impaired in the aged lung, and other mechanisms may be present to maintain an AM response to hypoxia.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Adrenomedullin, http://linkedlifedata.com/resource/pubmed/chemical/Calcitonin Receptor-Like Protein, http://linkedlifedata.com/resource/pubmed/chemical/Calcrl protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/Hypoxia-Inducible Factor 1, http://linkedlifedata.com/resource/pubmed/chemical/Mixed Function Oxygenases, http://linkedlifedata.com/resource/pubmed/chemical/Multienzyme Complexes, http://linkedlifedata.com/resource/pubmed/chemical/Protein Precursors, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Calcitonin, http://linkedlifedata.com/resource/pubmed/chemical/Xenopus Proteins, http://linkedlifedata.com/resource/pubmed/chemical/peptidylglycine monooxygenase, http://linkedlifedata.com/resource/pubmed/chemical/preproadrenomedullin
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1079-5006
pubmed:author
pubmed:issnType
Print
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
41-9
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:17301036-Adrenomedullin, pubmed-meshheading:17301036-Aging, pubmed-meshheading:17301036-Animals, pubmed-meshheading:17301036-Anoxia, pubmed-meshheading:17301036-Calcitonin Receptor-Like Protein, pubmed-meshheading:17301036-Disease Models, Animal, pubmed-meshheading:17301036-Electrophoresis, pubmed-meshheading:17301036-Gene Expression Regulation, Developmental, pubmed-meshheading:17301036-Hypoxia-Inducible Factor 1, pubmed-meshheading:17301036-Lung, pubmed-meshheading:17301036-Male, pubmed-meshheading:17301036-Mixed Function Oxygenases, pubmed-meshheading:17301036-Multienzyme Complexes, pubmed-meshheading:17301036-Polyribosomes, pubmed-meshheading:17301036-Protein Precursors, pubmed-meshheading:17301036-RNA, Messenger, pubmed-meshheading:17301036-Radioimmunoassay, pubmed-meshheading:17301036-Rats, pubmed-meshheading:17301036-Rats, Sprague-Dawley, pubmed-meshheading:17301036-Receptors, Calcitonin, pubmed-meshheading:17301036-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:17301036-Xenopus Proteins
pubmed:year
2007
pubmed:articleTitle
Age-related changes in adrenomedullin expression and hypoxia-inducible factor-1 activity in the rat lung and their responses to hypoxia.
pubmed:affiliation
Department of Physiology, Faculty of Medicine, University of Hong Kong, Pokfulam, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't