Detection of alkoxyl and carbon-centered free radicals in coronary sinus blood from patients undergoing elective cardioplegia

• Published in: Free radical biology & medicine Vol. 14; no. 4; pp. 421 - 426
• Main Authors: Tortolani, Anthony J., Powell, Saul R., Mišik, Vladimír, Weglicki, William B., Pogo, Gustave J., Kramer, Jay H.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.04.1993; Elsevier Science
• Subjects: Aged; Biological and medical sciences; Cardiopulmonary bypass; Cardiopulmonary Bypass - adverse effects; Cyclic N-Oxides; Electron Spin Resonance Spectroscopy; Female; Free Radicals; Heart Arrest, Induced - adverse effects; Humans; Ischemia; Male; Medical sciences; Middle Aged; Myocardial Reperfusion Injury - blood; Myocardial Reperfusion Injury - etiology; Myocardial Reperfusion Injury - prevention & control; Nitrogen Oxides; Reactive Oxygen Species - chemistry; Reactive Oxygen Species - metabolism; Spin Labels; Spin trapping; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the heart; α-Phenyl-tert-butylnitrone; Cardiopulmonary bypass; α-Phenyl-tert-butylnitrone; Free radicals; Ischemia; Spin trapping; Heart; Human; Surgery; Coronary artery; Circulatory system; Free radical; Blood
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/0891-5849(93)90091-8

Confirmation of the involvement of free radicals in postischemic injury in heart has been elusive. The present study was performed to determine the presence of free radicals in coronary sinus bloo patients undergoing elective open heart surgery and cardioplegia. Six patients who were scheduled for nonurgent elective open heart surgery were used in this study. Coronary sinus blood samples were withdrawn at 1, 3, 5, 10, 15, 20, and 25 min post-cross-clamp and immediately mixed with isosmotic α-phenyl- tert-Butylnitrone (PBN) and then centrifugated to obtain plasma. Plasmam samples were extacted with toluene and analyzed using electron spin resonance (ESR) spectroscopy. We observed ESR spectra consistent with the formation of alkoxyl and carbon-centered radical adducts of PBN (a N = 13.6 G, a β H = 1.9 G, and a N = 14.1 G, a β H = 4.2 G) in six of six patients. We obtained complete free radical production time courses during reperfusion from five patients, and all demonstrated a biphasic profile with an initial burst from 5 to 10 min followed by a second maxima at 25 min. Total PBN-adduct production during reperfusion increased in patients subjected to longer aortic cross-clamp times (global ischemia). These data demonstrate that postcardioplegia free radical production is detectable in coronary sinus blood using an ex vivo spin-trapping technique and that the extent of formation may be related to the severity of ischemia.