These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Alterations in cardiac membrane Ca2+ transport during oxidative stress.
    Author: Dixon IM, Kaneko M, Hata T, Panagia V, Dhalla NS.
    Journal: Mol Cell Biochem; 1990 Dec 20; 99(2):125-33. PubMed ID: 1962845.
    Abstract:
    Although cardiac dysfunction due to ischemia-reperfusion injury is considered to involve oxygen free radicals, the exact manner by which this oxidative stress affects the myocardium is not clear. As the occurrence of intracellular Ca2+ overload has been shown to play a critical role in the genesis of cellular damage due to ischemia-reperfusion, this study was undertaken to examine whether oxygen free radicals are involved in altering the sarcolemmal Ca2(+)-transport activities due to reperfusion injury. When isolated rat hearts were made globally ischemic for 30 min and then reperfused for 5 min, the Ca2(+)-pump and Na(+)-Ca2+ exchange activities were depressed in the purified sarcolemmal fraction; these alterations were prevented when a free radical scavenger enzymes (superoxide dismutase plus catalase) were added to the reperfusion medium. Both the Ca2(+)-pump and Na(+)-Ca2+ exchange activities in control heart sarcolemmal preparations were depressed by activated oxygen-generating systems containing xanthine plus xanthine oxidase and H2O2; these changes were prevented by the inclusion of superoxide dismutase and catalase in the incubation medium. These results support the view that oxidative stress during ischemia-reperfusion may contribute towards the occurrence of intracellular Ca2+ overload and subsequent cell damage by depressing the sarcolemmal mechanisms governing the efflux of Ca2+ from the cardiac cell.
    [Abstract] [Full Text] [Related] [New Search]