Linked Life Data

1890853

Source:http://linkedlifedata.com/resource/pubmed/id/1890853

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-10-15
pubmed:abstractText
The respiratory sinus arrhythmia (RSA) is a vagally mediated oscillation in cardiac cycle length at the frequency of breathing. We developed a mathematical model that predicted the temporal and frequency dependence of the RSA. We used the mathematical model to examine the underlying cellular basis for the RSA at the level of the sinus node. We alternated efferent vagal activity between a low and a high frequency at the frequency of breathing. This oscillation caused the rate of acetylcholine (ACh) release to oscillate between a low and a high rate at the frequency of breathing. ACh degradation followed linear pharmacokinetics for physiological concentrations of ACh. Therefore, the concentration of ACh in neuroeffector junctions of the sinus node oscillated at the frequency of breathing. Membrane potential responded rapidly to changes in the concentration of ACh relative to the rate of ACh degradation. Thus, the time course of the RSA depended on the rate of ACh degradation. Membrane potential oscillated at several integer multiples of frequency of breathing and at various higher frequencies, which were integer multiples of the frequency of breathing and the frequencies of firing of the sinus node. However, computing cardiac cycle length from membrane potential eliminated the higher frequencies. Therefore, cardiac cycle length oscillated at several integer multiples of the frequency of breathing, but not at these higher frequencies.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-5193
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
150
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
157-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Mathematical model of cellular basis for the respiratory sinus arrhythmia.
pubmed:affiliation
Department of Anesthesia, University of Iowa Hospitals, Iowa City 52242.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't