PEG-SOD improves postischemic functional recovery and antioxidant status in blood-perfused rabbit hearts.
The isolated blood-perfused rabbit heart, subjected to 60 min of cardioplegic arrest and 60 min of reperfusion, was used to assess the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) on postischemic recovery of left ventricular developed pressure (LVDP), the tissue activity of SOD, and tissue redox state. The five groups studied were the following: PEG-SOD-free control (group A), PEG-SOD as a pretreatment and as an additive during cardioplegia and reperfusion (group B), PEG-SOD as a pretreatment and a cardioplegic additive (group C), PEG-SOD in cardioplegia alone (group D), and PEG-SOD in reperfusion alone (group E). The results show that pretreatment with PEG-SOD improves postischemic recovery of LVDP (72 +/- 2% and 66 +/- 7 vs. 47 +/- 4% in groups B, C, and A, respectively). This protection was associated with an improved tissue redox state. Thus the ischemia-induced rise in oxidized glutathione was reduced from 313 +/- 26% (group A) to 162 +/- 15 and 138 +/- 14% (groups B and C, respectively), and the fall in reduced glutathione was attenuated from 51 +/- 5% to 35 +/- 6 and 13 +/- 5%, respectively. Tissue Mn-SOD activity was also conserved from 36 +/- 4% (group A) to 71 +/- 6 and 94 +/- 4% (groups B and C, respectively). No significant effect was seen when PEG-SOD was applied in cardioplegia or during reperfusion alone.
Qiu
Y
Y
Rayne Institute, St. Thomas' Hospital, London, United Kingdom.
Galiñanes
M
M
Ferrari
R
R
Cargnoni
A
A
Ezrin
A
A
Hearse
D J
DJ
D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001769:Blood; D003327:Coronary Disease / Q000503:physiopathology*; D005260:Female; D016166:Free Radical Scavengers; D006321:Heart / Q000503:physiopathology; D066298:In Vitro Techniques; D008297:Male; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism; D010084:Oxidation-Reduction; D010477:Perfusion; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011817:Rabbits; D013482:Superoxide Dismutase / Q000494:pharmacology*
D000975:Antioxidants; D016166:Free Radical Scavengers; D011092:Polyethylene Glycols; D013482:Superoxide Dismutase; C063471:polyethylene glycol-superoxide dismutase