Short-term exercise improves myocardial tolerance to in vivo ischemia-reperfusion in the rat
- ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
- Andrew Shanely Ph.D, Associate Professor (Creator)
- Institution
- Appalachian State University (ASU )
- Web Site: https://library.appstate.edu/
Abstract: These experiments examined the independent effects of short-term exercise and heat stress on myocardial responses during in vivo ischemia-reperfusion (I/R). Female Sprague-Dawley rats (4 mo old) were randomly assigned to one of four experimen- tal groups: 1) control, 2) 3 consecutive days of treadmill exercise [60 min/day at 60–70% maximal O2 uptake (V? O2 max)], 3) 5 consecutive days of treadmill exercise (60 min/day at 60–70% V? O2 max), and 4) whole body heat stress (15 min at 42°C). Twenty-four hours after heat stress or exercise, animals were anesthetized and mechanically venti- lated, and the chest was opened by thoracotomy. Coronary occlusion was maintained for 30-min followed by a 30-min period of reperfusion. Compared with control, both heat- stressed animals and exercised animals (3 and 5 days) main- tained higher (P < 0.05) left ventricular developed pressure (LVDP), maximum rate of left venticular pressure develop- ment (+dP/dt), and maximum rate of left ventricular pres- sure decline (-dP/dt) at all measurement periods during both ischemia and reperfusion. No differences existed between heat-stressed and exercise groups in LVDP, +dP/dt, and -dP/dt at any time during ischemia or reperfusion. Both heat stress and exercise resulted in an increase (P < 0.05) in the relative levels of left ventricular heat shock protein 72 (HSP72). Furthermore, exercise (3 and 5 days) increased (P < 0.05) myocardial glutathione levels and manganese superoxide dismutase activity. These data indicate that 3–5 consecutive days of exercise improves myocardial contractile performance during in vivo I/R and that this exercise-induced myocardial protection is associated with an increase in both myocardial HSP72 and cardiac antioxidant defenses
Short-term exercise improves myocardial tolerance to in vivo ischemia-reperfusion in the rat
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Additional Information
- Publication
- Demirel, Haydar A., Scott K. Powers, Murat A. Zergeroglu, R. Andrew Shanely, Karyn Hamilton, Jeff Coombes, and Hisashi Naito (2001) "Short-term exercise improves myocardial tolerance to in vivo ischemia-reperfusion in the rat" Journal of Applied Physiology #91 pp.2205-2212 Version of Record Available @ (http://0-jap.physiology.org.wncln.wncln.org/content/91/5/2205.short)
- Language: English
- Date: 2001
- Keywords
- endurance exercise, heart, reactive oxygen species, heat shock proteins, lipid peroxidation, antioxidant enzymes