Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

ATP release by cardiac myocytes in a simulated ischaemia model

Clarke, Thomas Charles, Williams, Oliver J. S., Martin, Patricia E. and Evans, William Howard 2009. ATP release by cardiac myocytes in a simulated ischaemia model. European Journal of Pharmacology 605 (1-3) , pp. 9-14. 10.1016/j.ejphar.2008.12.005

Full text not available from this repository.

Abstract

We studied the role of connexin hemichannels in the release of ATP by neonatal cardiac myocytes subject to ischaemic stress. Mechanical, osmotic and oxidative stress and changes in extracellular or intracellular Ca^2^+ levels induce connexin hemichannels located in the plasma membrane to open and release small ions and molecules with signaling potential such as ATP. Since ATP release has been implicated in adaptation to oxygen deprivation, we studied its release by cardiac myocytes incubated in a custom-built hypoxia chamber for various periods. In a simulated ischaemia model (0.5% oxygen and 0.2 g/l glucose) a peak of ATP release occurred at 80 min followed by a return to steady state levels for a further 200 min. This peak of ATP release was not observed in myocytes subject to hypoxia (0.5% oxygen, 3.0 g/l glucose). ATP release in ischaemia was influenced by two classes of reagents that target connexins, the channel forming proteins of gap junctions. First, the connexin hemichannel inhibitors Gap 26 and 18a glycyrrhetinic acid abolished the ATP peak of release. Second, the AAP10, a peptide with antiarrhythmic properties markedly increased the peak of ATP release observed at 80 min of ischaemia and also induced a second smaller peak at 180-240 min. ATP content of the myocytes and Cx43 phosphorylation were monitored. Since the release of ATP in ischaemia was abolished by connexin channel inhibitors and stimulated by a peptide developed to target connexins in the context of cardiac arrhythmia, the results suggest that nucleotide release by connexin hemichannels is likely to feature in the response of myocytes to ischaemic stress in the heart.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Medicine
Subjects: R Medicine > R Medicine (General)
Uncontrolled Keywords: Connexin hemichannel; Hypoxia; Ischaemia; Gap26; AAP10; Cardiac myocyte; ATP; Ischaemic pre-conditioning
Publisher: Elsevier
ISSN: 0014-2999
Last Modified: 06 Aug 2020 15:16
URI: http://orca-mwe.cf.ac.uk/id/eprint/24764

Citation Data

Cited 47 times in Google Scholar. View in Google Scholar

Cited 63 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item