“Although adenosine and S-nitroso-N-acetyl-penicillamine each alone did … flavoprotein fluorescence, nor did they confer significant cardioprotection, coadministration of adenosine and S-nitroso-…-acetyl-penicillamine with isoflurane conferred a highly significant reduction of infarct size and improvement … left ventricular function without increasing flavoprotein oxidation over isoflurane alone.”