CARDIOPROTECTIVE EFFECTS OF DIHYDROLIPOIC ACID AND TOCOPHEROL IN RIGHT HEART HYPERTROPHY DURING OXIDATIVE STRESS

Rat hearts hypertrophied by exposure of the animals to low oxygen pres sure were perfused by the Langendorff technique. After oxidative stres s induced by hypoxia/reoxygenation, functional recovery of the hypertr ophied right heart was insufficient when compared to non-hypertrophied controls. Accordingly, mitochondrial membrane potential did not recov er sufficiently. There was a positive trend for improvement of the rat e-pressure product during reoxygenation in lipoic acid (GAS 1077-28-7; 0.8 mu mol/l) treated hearts which was also verified for membrane pot ential. Adenosine 5'-triphosphate and creatine phosphate contents as w ell as the ATP/ADP ratio in hypertrophied right ventricle were signifi cantly increased after reoxygenation in hearts treated with lipoic aci d. With lipoic acid, there was a significantly higher content of gluta thione (oxidized form) after reoxygenation, Ca2+ uptake was significan tly increased in mitochondria isolated from hypertrophied right ventri cles and treated by 12 nmol/mg protein of lipoic acid. The results rev eal a distinct improvement of mitochondrial structure/function by lipo ic acid and suggest for therapy a combination with the synergistic fre e radical scavenging properties of tocopherol (GAS 10191-41-0).