dc.contributor.author |
Power, Amelia |
en |
dc.contributor.author |
Kaur, Sarbjot |
en |
dc.contributor.author |
Dyer, C |
en |
dc.contributor.author |
Ward, Marie-Louise |
en |
dc.coverage.spatial |
Hamburg, Germany |
en |
dc.date.accessioned |
2018-10-16T22:17:20Z |
en |
dc.date.issued |
2017-07-24 |
en |
dc.identifier.issn |
0022-2828 |
en |
dc.identifier.uri |
http://hdl.handle.net/2292/42157 |
en |
dc.description.abstract |
Background: Reduced contractility is a hallmark of failing hearts, often linked to depressed Ca2+ transients, since Ca2+ is the key activator of contraction. Impaired excitation-contraction coupling has been observed in conjunction with structural alterations to the t-tubular system. However, many sub-cellular changes occur in heart failure, making it difficult to determine the contribution of disrupted t-tubules. Our aim was to quantify the impact of detubulation on Ca2+ handling and contraction in otherwise healthy ventricular tissue. Methods: Measurement of [Ca2+]i (fura-2) and stress were made in RV trabeculae from rat hearts before and after detubulation following formamide treatment (1.5 M, 5 min). The effect of detubulation on two important regulatory mechanisms was also investigated: the response to stretch, and to β-adrenergic stimulation (0.1 μM isoproterenol). Results: De-tubulation of trabeculae slowed the time course of the Ca2+ transients and twitch force: time-to-peak, maximum rate-of-rise, and relaxation were prolonged in both. The slow force response to stretch was decreased following detubulation, and the response to β-adrenergic activation blunted. Conclusions: This study enabled us to examine the effect of detubulation on Ca2+ transients and twitch force in tissue from non-failing hearts in which expression of the different Ca2+ handling proteins was not altered by any disease process. Our results demonstrate the importance of an intact t-tubular system on the kinetics of excitation-contraction coupling, as well as on mechanisms that regulate contractility in vivo: the response to stretch and β-adrenergic stimulation. |
en |
dc.publisher |
Academic Press |
en |
dc.relation.ispartof |
34th Annual Meeting, European Section of the International Society for Heart Research |
en |
dc.relation.ispartofseries |
Journal of Molecular and Cellular Cardiology |
en |
dc.rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. |
en |
dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
en |
dc.title |
The impact of t-tubule disruption on excitation-contraction coupling and calcium handling in rat ventricular trabeculae |
en |
dc.type |
Conference Item |
en |
pubs.begin-page |
42 |
en |
pubs.volume |
109 |
en |
dc.rights.holder |
Copyright: The author |
en |
pubs.end-page |
42 |
en |
pubs.finish-date |
2017-07-27 |
en |
pubs.start-date |
2017-07-24 |
en |
dc.rights.accessrights |
http://purl.org/eprint/accessRights/RestrictedAccess |
en |
pubs.subtype |
Proceedings |
en |
pubs.elements-id |
654743 |
en |
pubs.org-id |
Medical and Health Sciences |
en |
pubs.org-id |
Medical Sciences |
en |
pubs.org-id |
Physiology Division |
en |
pubs.record-created-at-source-date |
2017-08-29 |
en |