Prevention of myocardial reperfusion injury by poly(ADP-ribose) synthetase inhibitor, 3-aminobenzamide, in cardioplegic solution: in vitro study of isolated rat heart model.
OBJECTIVE
Cardioplegic arrest remains the method of choice for myocardial protection in cardiac surgery. Poly(adenosine 5'-diphosphate-ribose) synthetase (PARS) inhibitor has been suggested to attenuate the ischemia-reperfusion injury in myocardial infarction by preventing energy depletion associated with oxidative stress. We investigated the efficacy of a cardioplegic solution containing a PARS inhibitor, 3-aminobenzamide (3-AB), for myocardial protection against ischemia-reperfusion injury caused by cardioplegic arrest.


METHODS
Isolated hearts were set on a Langendorff apparatus and perfused. The hearts were arrested for 90 min with a cardioplegic solution given at 30-min intervals and then reperfused for 20 min. The hearts of rat in the 3-AB(-) group (n = 8) were perfused with a standard cardioplegic solution and terminal warm cardoplegia, whereas the 3-AB(+) group (n = 8) received these solutions supplemented with 3-AB (100 microM). Left ventricular function and release of cardiac enzymes were monitored before and after cardioplegic arrest. After reperfusion, NAD+ (nicotinamide-adenine dinucleotide) levels were assessed, and the tissues were examined immunohistochemically for oxidative stress and apoptosis.


RESULTS
During reperfusion, the 3-AB(+) group showed significantly higher (P = 0.005)dp/dt and lower creatine phosphokinase (CPK) level and glucotamic-oxaloacetic transaminase (GOT) in the effluent (CPK; P = 0.003 GOT; P < 0.001) The cardiomyocytes of the 3-AB(+) group also preserved a higher NAD+ level (P < 0.001). Immunohistochemical study of oxidative stress revealed a lesser extent (P = 0.007) of nuclear staining and a lower fraction of apoptosis in the 3-AB(+) group.


CONCLUSIONS
Cardioplegic solution supplemented with 3-AB provides efficient myocardial protection in cardioplegic ischemic reperfusion by suppressing oxidative stress and overactivation of PARS.
Department of Cardiovascular Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-machi, Sakyo-ku, 606-8507, Kyoto, Japan.
Kazuhiro
K
Yamazaki
Senri
S
Miwa
Kunihiro
K
Ueda
Seigo
S
Tanaka
Shinya
S
Toyokuni
Oriyanhan
O
Unimonh
Kazunobu
K
Nishimura
Masashi
M
Komeda
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001549:Benzamides / Q000494:pharmacology*; D006348:Cardiac Surgical Procedures; D002314:Cardioplegic Solutions / Q000494:pharmacology*; D004247:DNA / Q000378:metabolism; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects; D006324:Heart Arrest, Induced / Q000379:methods; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D009206:Myocardium / Q000201:enzymology; D009243:NAD / Q000032:analysis; D018384:Oxidative Stress; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology
D001549:Benzamides; D002314:Cardioplegic Solutions; D004791:Enzyme Inhibitors; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D009243:NAD; C025160:3-aminobenzamide; D004247:DNA