Experimental physiology
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Experimental physiology · Aug 2012
Comparative StudyRemote ischaemic pre- and delayed postconditioning - similar degree of cardioprotection but distinct mechanisms.
Myocardial ischaemia-reperfusion injury can be significantly reduced by an episode(s) of ischaemia-reperfusion applied prior to or during myocardial ischaemia (MI) to peripheral tissue located at a distance from the heart; this phenomenon is called remote ischaemic conditioning (RIc). Here, we compared the efficacy of RIc in protecting the heart when the RIc stimulus is applied prior to, during and at different time points after MI. A rat model of myocardial ischaemia-reperfusion injury involved 30 min of left coronary artery occlusion followed by 120 min of reperfusion. ⋯ Cardioprotection conferred by delayed remote postconditioning was not affected by either vagotomy or peripheral denervation. These results indicate that RIc confers potent cardioprotection even if applied with a significant delay after the onset of myocardial reperfusion. Cardioprotection by remote preconditioning is critically dependent on afferent innervation of the remote organ and intact parasympathetic activity, while delayed remote postconditioning appears to rely on a different signalling pathway(s).