Preserved mitochondrial calcium retention capacity in summer‐active Arctic ground squirrels undergoing normothermic myocardial ischemia/reperfusion injury (663.9)
Abstract
Arctic Ground Squirrels (AGS) exhibit a high degree of endogenous resistance against myocardial ischemia/reperfusion (IR) injury compared to the best protected rat strain (Brown Norway, BN). We tested if this species‐specific myocardial protection is associated with increased mitochondrial calcium retention capacity (CRC). Isolated hearts from BN (n=15) and summer‐active AGS (n=11) underwent 45 min global cardioplegic ischemia and 60 min reperfusion with Krebs solution containing 7.5 mM glucose or 1% Intralipid in addition. Left ventricular pressure was measured isovolumetrically. Cardiac mitochondria were isolated and CRC was measured by spectrofluorometry of calcium green at 503/532 nm excitation/emission for complex I and II substrates in response to intermittent calcium boluses. While multiple regression analysis revealed intralipid, female gender and species (AGS) as predictors of better myocardial function following IR, predictors of improved CRC were AGS and mitochondrial substrate only. These results add to our previous reports of species‐dependent mitochondrial coupling of oxidative phosphorylation as the most important predictor of cardioprotection in our model and underline the importance of broadly preserved mitochondrial function as a key element of attenuated IR injury. Supported by Department of Veterans Affairs (CARA‐026‐10F), NSF, NIH, USAMRMC, FAER and institutional funds.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 01, 2014
- Source ID
- 10.1096/fasebj.28.1_supplement.663.9
Entities
People
- Brian C. Barnes
- Gurpreet Dulai
- Matthias Riess
- Mihai Podgoreanu
- Quintin Quinones
Organizations
- Duke University
- Foundation for Anesthesia Education and Research
- Medical College of Wisconsin
- National Institutes of Health
- National Science Foundation
- United States Army Medical Research and Development Command
- United States Department of Veterans Affairs
- University of Alaska System
- Veterans Health Administration