Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2005-1-13
pubmed:abstractText
Though the mechanics of breathing differ fundamentally between amniotes and "lower" vertebrates, homologous rhythm generators may drive air breathing in all lunged vertebrates. In both frogs and rats, two coupled oscillators, one active during the inspiratory (I) phase and the other active during the preinspiratory (PreI) phase, have been hypothesized to generate the respiratory rhythm. We used opioids to uncouple these oscillators. In the intact rat, complete arrest of the external rhythm by opioid-induced suppression of the putative I oscillator, that is, pre-Bötzinger complex (PBC) oscillator, did not arrest the putative PreI oscillator. In the unanesthetized frog, the comparable PreI oscillator, that is, the putative buccal/gill oscillator, was refractory to opioids even though the comparable I oscillator, the putative lung oscillator, was arrested. Studies in en bloc brainstem preparations derived from both juvenile frogs and metamorphic tadpoles confirmed these results and suggested that opioids may play a role in the clustering of lung bursts into episodes. As the frog and rat respiratory circuitry produce functionally equivalent motor outputs during lung inflation, these data argue for a close homology between the frog and rat oscillators. We suggest that the respiratory rhythm of all lunged vertebrates is generated by paired coupled oscillators. These may have originated from the gill and lung oscillators of the earliest air breathers.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-3034
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
369-85
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15551345-Action Potentials, pubmed-meshheading:15551345-Analysis of Variance, pubmed-meshheading:15551345-Animals, pubmed-meshheading:15551345-Biological Clocks, pubmed-meshheading:15551345-Brain Stem, pubmed-meshheading:15551345-Dose-Response Relationship, Drug, pubmed-meshheading:15551345-Enkephalin, Ala(2)-MePhe(4)-Gly(5)-, pubmed-meshheading:15551345-Fentanyl, pubmed-meshheading:15551345-Gills, pubmed-meshheading:15551345-Hypercapnia, pubmed-meshheading:15551345-Larva, pubmed-meshheading:15551345-Lung, pubmed-meshheading:15551345-Male, pubmed-meshheading:15551345-Models, Biological, pubmed-meshheading:15551345-Naloxone, pubmed-meshheading:15551345-Narcotic Antagonists, pubmed-meshheading:15551345-Narcotics, pubmed-meshheading:15551345-Nerve Net, pubmed-meshheading:15551345-Periodicity, pubmed-meshheading:15551345-Photoplethysmography, pubmed-meshheading:15551345-Physical Conditioning, Animal, pubmed-meshheading:15551345-Ranidae, pubmed-meshheading:15551345-Rats, pubmed-meshheading:15551345-Rats, Wistar, pubmed-meshheading:15551345-Respiration, pubmed-meshheading:15551345-Respiratory Physiological Phenomena, pubmed-meshheading:15551345-Vagotomy
pubmed:year
2005
pubmed:articleTitle
Ancient gill and lung oscillators may generate the respiratory rhythm of frogs and rats.
pubmed:affiliation
Department of Medicine, University of Calgary, 3330 Hospital Drive, Calgary, Alberta, Canada T2N 4N1.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, Non-U.S. Gov't