Journal article
Regional distribution of T-tubule density in left and right atria in dogs
Heart rhythm, Vol.14(2), pp.273-281
02/2017
DOI: 10.1016/j.hrthm.2016.09.022
PMCID: PMC5484147
PMID: 27670628
Abstract
The peculiarities of transverse tubule (T-tubule) morphology and distribution in the atrium—and how they contribute to excitation-contraction coupling—are just beginning to be understood.
The objectives of this study were to determine T-tubule density in the intact, live right and left atria in a large animal and to determine intraregional differences in T-tubule organization within each atrium.
Using confocal microscopy, T-tubules were imaged in both atria in intact, Langendorf-perfused normal dog hearts loaded with di-4-ANEPPS. T-tubules were imaged in large populations of myocytes from the endocardial surface of each atrium. Computerized data analysis was performed using a new MatLab (Mathworks, Natick, MA) routine, AutoTT.
There was a large percentage of myocytes that had no T-tubules in both atria with a higher percentage in the right atrium (25.1%) than in the left atrium (12.5%) (P < .02). The density of transverse and longitudinal T-tubule elements was low in cells that did contain T-tubules, but there were no significant differences in density between the left atrial appendage, the pulmonary vein-posterior left atrium, the right atrial appendage, and the right atrial free wall. In contrast, there were significant differences in sarcomere spacing and cell width between different regions of the atria.
There is a sparse T-tubule network in atrial myocytes throughout both dog atria, with significant numbers of myocytes in both atria—the right atrium more so than the left atrium—having no T-tubules at all. These regional differences in T-tubule distribution, along with differences in cell width and sarcomere spacing, may have implications for the emergence of substrate for atrial fibrillation.
Details
- Title: Subtitle
- Regional distribution of T-tubule density in left and right atria in dogs
- Creators
- Rishi Arora - Northwestern UniversityGary L. Aistrup - Northwestern UniversityStephen Supple - Northwestern UniversityCaleb Frank - Northwestern UniversityJasleen Singh - Northwestern UniversityShannon Tai - Northwestern UniversityAnne Zhao - Northwestern UniversityLaura Chicos - Northwestern UniversityWilliam Marszalec - Northwestern UniversityAng Guo - University of IowaLong-Sheng Song - University of IowaJ. Andrew Wasserstrom - Northwestern University
- Resource Type
- Journal article
- Publication Details
- Heart rhythm, Vol.14(2), pp.273-281
- DOI
- 10.1016/j.hrthm.2016.09.022
- PMID
- 27670628
- PMCID
- PMC5484147
- NLM abbreviation
- Heart Rhythm
- ISSN
- 1547-5271
- eISSN
- 1556-3871
- Publisher
- Elsevier Inc
- Language
- English
- Date published
- 02/2017
- Academic Unit
- Cardiovascular Medicine; Fraternal Order of Eagles Diabetes Research Center; Biochemistry and Molecular Biology; Internal Medicine
- Record Identifier
- 9984293087202771
Metrics
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