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From the *Department of Anesthesiology;
Laboratory of Experimental Anesthesiology and Cellular Physiology; and
Department of Cardiac and Thoracic Surgery, CHU Caen, France.
Address correspondence and reprint requests to Dr. Jean-Luc Hanouz, Département dAnesthésie-Réanimation, CHU de Caen, Avenue Côte de Nacre, 14033 Caen Cedex, France. Address e-mail to hanouz-jl{at}chu-caen.fr.
Abstract
BACKGROUND: We examined the role of reactive oxygen species (ROS) in sevoflurane- and desflurane-induced preconditioning on isolated human right atrial myocardium.
METHODS: We recorded isometric contraction of human right atrial trabeculae suspended in an oxygenated Tyrodes solution (34°C, stimulation frequency 1 Hz). In all groups, a 30-min hypoxic period was followed by 60 min of reoxygenation. Ten minutes before hypoxia reoxygenation, muscles were exposed to 5 min of sevoflurane 2% or desflurane 6%. In separate groups, the sevoflurane 2% (Sevo + N-(2-mercaptopropionyl)-glycine [MPG]) or desflurane 6% (Des + MPG) was administered in the presence of 0.1 mM MPG, a ROS scavenger. The effect of 0.1 mM MPG alone was tested. Recovery of force after a 60-min reoxygenation period was compared between groups (mean ± sd).
RESULTS: Preconditioning with sevoflurane 2% (85% ± 4% of baseline) or desflurane 6% (86% ± 7% of baseline) enhanced the recovery of the force of myocardial contraction after 60 min reoxygenation compared with the control group (53% ± 11% of baseline, P < 0.001). This effect was abolished in the presence of MPG (56% ± 12% of baseline for Sevo + MPG, 48% ± 13% of baseline for Des + MPG). The effect of MPG alone on the recovery of force was not different from the control group (57% ± 7% of baseline versus 53% ± 11%; P = NS).
CONCLUSIONS: In vitro, sevoflurane and desflurane preconditioned human myocardium against hypoxia through a ROS-dependent mechanism.
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