Myocardial antioxidant defenses during cardiopulmonary bypass.
In 31 male patients undergoing coronary bypass surgery who underwent different periods of cardioplegic hypothermic arrest, the activities of glutathione peroxidase, glutathione reductase, glutathione transferase, copper/zinc-containing and manganese-containing superoxide dismutases, and catalase were studied in the right atrial myocardium, before and 5 minutes after aortic cross-clamping. The levels of thiobarbituric acid reactive substances (TBARS) and nonproteic thiol compounds (NP-SH) were also assessed. Prolonged ischemia followed by reperfusion induced activation of the major myocardial antioxidant enzymes with marked NP-SH depression and TBARS increase, despite cold crystalloid cardioplegic protection. These changes were significantly related to the duration of the ischemic arrest, suggesting: (1) that reperfusion free radical generation is dependent on the severity of the previous ischemic period; and (2) the occurrence of myocardial oxidative stress during cardiopulmonary bypass.
Mezzetti
A
A
Laboratorio di Fisiopatologia Medica Sperimentale, Cattedra di Patologia Medica, Università di Chieti, Italy.
Lapenna
D
D
Pierdomenico
S D
SD
Di Giammarco
G
G
Bosco
G
G
Di Ilio
C
C
Santarelli
P
P
Calafiore
A M
AM
Cuccurullo
F
F
D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D002315:Cardiopulmonary Bypass; D002374:Catalase / Q000378:metabolism; D003327:Coronary Disease / Q000201:enzymology*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006324:Heart Arrest, Induced; D006325:Heart Atria / Q000201:enzymology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000201:enzymology*; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D013997:Time Factors
D000975:Antioxidants; D013438:Sulfhydryl Compounds; D017392:Thiobarbituric Acid Reactive Substances; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005982:Glutathione Transferase