Heterogeneity of T-Tubules in Pig Hearts
| Autor: | Gadeberg, Hanne C., Bond, Richard C., Kong, Cherrie H. T., Chanoit, Guillaume P., Ascione, Raimondo, Cannell, Mark B., James, Andrew F. |
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| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
Livestock
Swine Heart Ventricles Cell Membranes Muscle Tissue Geometry lcsh:Medicine Research and Analysis Methods Sarcolemmas Model Organisms Sarcolemma Animal Cells Pig Models Medicine and Health Sciences Animals Myocytes Cardiac Calcium Signaling Heart Atria lcsh:Science Excitation Contraction Coupling Cell Size Mammals Staining Muscle Cells Microscopy Confocal lcsh:R Organisms Biology and Life Sciences Cell Staining Agriculture Heart Cell Biology Animal Models Myocardial Contraction Biological Tissue Radii Specimen Preparation and Treatment Vertebrates Amniotes Physical Sciences Cardiovascular Anatomy cardiovascular system Female lcsh:Q Cellular Types Anatomy Cellular Structures and Organelles Mathematics Research Article |
| Zdroj: | PLoS ONE, Vol 11, Iss 6, p e0156862 (2016) PLoS ONE |
| ISSN: | 1932-6203 |
| Popis: | Background T-tubules are invaginations of the sarcolemma that play a key role in excitation-contraction coupling in mammalian cardiac myocytes. Although t-tubules were generally considered to be effectively absent in atrial myocytes, recent studies on atrial cells from larger mammals suggest that t-tubules may be more numerous than previously supposed. However, the degree of heterogeneity between cardiomyocytes in the extent of the t-tubule network remains unclear. The aim of the present study was to investigate the t-tubule network of pig atrial myocytes in comparison with ventricular tissue. Methods Cardiac tissue was obtained from young female Landrace White pigs (45–75 kg, 5–6 months old). Cardiomyocytes were isolated by arterial perfusion with a collagenase-containing solution. Ca2+ transients were examined in field-stimulated isolated cells loaded with fluo-4-AM. Membranes of isolated cells were visualized using di-8-ANEPPS. T-tubules were visualized in fixed-frozen tissue sections stained with Alexa-Fluor 488-conjugated WGA. Binary images were obtained by application of a threshold and t-tubule density (TTD) calculated. A distance mapping approach was used to calculate half-distance to nearest t-tubule (HDTT). Results & Conclusion The spatio-temporal properties of the Ca2+ transient appeared to be consistent with the absence of functional t-tubules in isolated atrial myocytes. However, t-tubules could be identified in a sub-population of atrial cells in frozen sections. While all ventricular myocytes had TTD >3% (mean TTD = 6.94±0.395%, n = 24), this was true of just 5/22 atrial cells. Mean atrial TTD (2.35±0.457%, n = 22) was lower than ventricular TTD (P3% (1.65±0.06 μm, n = 5, P |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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