Application of high-dose propofol during ischemia improves postischemic function of rat hearts: effects on tissue antioxidant capacity.

Centre for Anesthesia and Analgesia, Department of Pharmacology and Therapeutics, University of British Columbia, Vancouver, Canada.
Canadian Journal of Physiology and Pharmacology (Impact Factor: 1.56). 11/2004; 82(10):919-26. DOI: 10.1139/y04-097
Source: PubMed

ABSTRACT Previous studies have shown that reactive oxygen species mediated lipid peroxidation in patients undergoing cardiac surgery occurs primarily during cardiopulmonary bypass. We examined whether application of a high concentration of propofol during ischemia could effectively enhance postischemic myocardial functional recovery in the setting of global ischemia and reperfusion in an isolated heart preparation. Hearts were subjected to 40 min of global ischemia followed by 90 min of reperfusion. During ischemia, propofol (12 microg/mL in saline) was perfused through the aorta at 60 microL/min. We found that application of high-concentration propofol during ischemia combined with low-concentration propofol (1.2 microg/mL) administered before ischemia and during reperfusion significantly improved postischemic myocardial functional recovery without depressing cardiac mechanics before ischemia, as is seen when high-concentration propofol was applied prior to ischemia and during reperfusion. The functional enhancement is associated with increased heart tissue antioxidant capacity and reduced lipid peroxidation. We conclude that high-concentration propofol application during ischemia could be a potential therapeutic and anesthetic strategy for patients with preexisting myocardial dysfunction.

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