Linked Life Data

17869150

Source:http://linkedlifedata.com/resource/pubmed/id/17869150

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2007-10-2
pubmed:abstractText
Pacific tarpon (Megalops cyprinoides) use a modified gas bladder as an air-breathing organ (ABO). We examined changes in cardiac output (V(b)) associated with increases in air-breathing that accompany exercise and aquatic hypoxia. Juvenile (0.49 kg) and adult (1.21 kg) tarpon were allowed to recover in a swim flume at 27 degrees C after being instrumented with a Doppler flow probe around the ventral aorta to monitor V(b) and with a fibre-optic oxygen sensor in the ABO to monitor air-breathing frequency. Under normoxic conditions and in both juveniles and adults, routine air-breathing frequency was 0.03 breaths min(-1) and V(b) was about 15 mL min(-1) kg(-1). Normoxic exercise (swimming at about 1.1 body lengths s(-1)) increased air-breathing frequency by 8-fold in both groups (reaching 0.23 breaths min(-1)) and increased V(b) by 3-fold for juveniles and 2-fold for adults. Hypoxic exposure (2 kPa O2) at rest increased air-breathing frequency 19-fold (to around 0.53 breaths min(-1)) in both groups, and while V(b) again increased 3-fold in resting juvenile fish, V(b) was unchanged in resting adult fish. Exercise in hypoxia increased air-breathing frequency 35-fold (to 0.95 breaths min(-1)) in comparison with resting normoxic fish. While juvenile fish increased V(b) nearly 2-fold with exercise in hypoxia, adult fish maintained the same V(b) irrespective of exercise state and became agitated in comparison. These results imply that air-breathing during exercise and hypoxia can benefit oxygen delivery, but to differing degrees in juvenile and adult tarpon. We discuss this difference in the context of myocardial oxygen supply.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1095-6433
pubmed:author
pubmed:issnType
Print
pubmed:volume
148
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
562-71
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Changes in cardiac output during swimming and aquatic hypoxia in the air-breathing Pacific tarpon.
pubmed:affiliation
Environmental Biology, School of Earth and Environmental Sciences, University of Adelaide, Adelaide 5005, Australia. timothy.clark.mail@gmail.com
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't