HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 295/2/R681    most recent 90303.2008v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by McAllister, S. E. Articles by Pang, C. Y. Search for Related Content PubMed PubMed Citation Articles by McAllister, S. E. Articles by Pang, C. Y.

COMPARATIVE AND EVOLUTIONARY PHYSIOLOGY

Postconditioning for salvage of ischemic skeletal muscle from reperfusion injury: efficacy and mechanism

¹Research Institute, The Hospital for Sick Children and Departments of ²Surgery and ³Physiology, University of Toronto, Toronto, Ontario, Canada; and ⁴Department of Surgery, University of Washington, Seattle, Washington

Submitted 20 March 2008 ; accepted in final form 26 May 2008

We tested our hypothesis that postischemic conditioning (PostC) is effective in salvage of ischemic skeletal muscle from reperfusion injury and the mechanism involves inhibition of opening of the mitochondrial permeability transition pore (mPTP). In bilateral 8 x 13 cm pig latissimus dorsi muscle flaps subjected to 4 h ischemia, muscle infarction increased from 22 ± 4 to 41 ± 1% between 2 and 24 h reperfusion and remained unchanged at 48 (38 ± 6%) and 72 (40 ± 1%) h reperfusion (P < 0.05; n = 4 pigs). PostC induced by four cycles of 30-s reperfusion/reocclusion at the onset of reperfusion after 4 h ischemia reduced muscle infarction from 44 ± 2 to 22 ± 2% at 48 h reperfusion. This infarct protective effect of PostC was mimicked by intravenous injection of the mPTP opening inhibitor cyclosporin A or NIM-811 (10 mg/kg) at 5 min before the end of 4 h ischemia and was abolished by intravenous injection of the mPTP opener atractyloside (10 mg/kg) at 5 min before PostC (P < 0.05; n = 4–5 pigs). PostC or intravenous cyclosporin A injection at 5 min before reperfusion caused a decrease in muscle myeloperoxidase activity and mitochondrial free Ca²⁺ concentration and an increase in muscle ATP content after 4 h ischemia and 2 h reperfusion compared with the time-matched controls. These effects of PostC were abolished by intravenous injection of atractyloside at 5 min before PostC (P < 0.05; n = 6 pigs). These observations support our hypothesis that PostC is effective in salvage of ischemic skeletal muscle from reperfusion injury and the mechanism involves inhibition of opening of the mPTP.

skeletal muscle postconditioning; mitochondrial permeability transition pore; neutrophil accumulation; mitochondrial calcium content; 5'-adenosine triphosphate synthesis

This article has been cited by other articles:

				S. E. McAllister, M. A. Moses, K. Jindal, H. Ashrafpour, N. J. Cahoon, N. Huang, P. C. Neligan, C. R. Forrest, J. E. Lipa, and C. Y. Pang Na+/H+ exchange inhibitor cariporide attenuates skeletal muscle infarction when administered before ischemia or reperfusion J Appl Physiol, January 1, 2009; 106(1): 20 - 28. [Abstract] [Full Text] [PDF]