Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 2
pubmed:dateCreated
1989-12-28
pubmed:abstractText
Impulse propagation and histology were studied in adult and neonatal canine Bachmann's bundle. Both showed nonuniform electrical anisotropy: effective longitudinal conduction velocity (theta L) markedly exceeded effective transverse conduction velocity (theta T), and extracellular potential waveforms with transverse propagation were polyphasic. An age difference in theta L (0.80 m/s neonate, 1.31 m/s adult) was found; it could be largely accounted for by a difference in myocyte diameter (4.7 microns neonate, 17.1 microns adult). Close apposition of myocytes in the neonate and development of transverse tubules in the adult may have influenced theta L at each stage. Perimysial septa separated fascicles in both neonatal and adult bundles; however, endomysial septa between individual myocytes were completely developed only in adult bundles. Thus perimysial septa were much more responsible for nonuniform anisotropy and low theta T than endomysial septa. Fascicle diameter and length were greater in the adult, which may have affected transverse propagation. Specialized conduction system cells could not be identified.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
257
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1446-57
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Structure of canine Bachmann's bundle related to propagation of excitation.
pubmed:affiliation
Department of Pediatrics, Duke University Medical Center, Durham, North Carolina 27710.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.