Decreased SOD activity and increased nitrates level in rat heart with left ventricular hypertrophy induced by isoproterenol.

Left ventricular hypertrophy is considered a risk for cardiac failure. In an attempt to understand the molecular basis of antioxidant changes during ventricular hypertrophy, we have used isoproterenol treated rats. Our studies showed that administration of high doses of isoproterenol induced oxidative and nitrosative stress, expressed as decreased level of thiols (SH), decreased superoxide dismutase (SOD) activity and increased nitrates level in the rat heart.

Activity of Na+/K+-ATPase and of Ca++-ATPase under the action of adenosine triphosphate in experimental myocardial hypertrophy.

This paper presents the results of our research on the mechanisms involved in the modifications occurring in the activity of ionic pumps (Na+/K+-ATPase and Ca++-ATPase) at the level of the sarcolemma, the sarcoplasmic reticulum and mitochondrial membrane of the myocardial cell in experimental myocardial hypertrophy induced by isoproterenol. We also studied the effects of concomitant administration of adenosine triphosphate. Thus, we found the activity of the sarcolemmal Ca++-ATPase intensely increased under the action of isoproterenol, while Ca++-ATPase activity in the sarcoplasmic reticulum decreased significantly.

Influence of isoproterenol-induced cardiac hypertrophy on oxydative myocardial stress.

The purpose of this research has been to assess the role of lipidic peroxides, the involvement of the superoxide radical and of sulfhydrylic groups in isoproterenol-induced myocardium hypertrophy in rats. The results of our investigations point to increased values by 25% of plasma lipidic peroxides and in the myocardium and to a decrease of sulfhydrylic groups and of superoxide dismutase in the groups with myocardial hypertrophy, 15% and 10% respectively, compared to the controls. The comparative analysis of the data enabled us to infer the consequences of lipidic peroxides and of free radicals presence in excess and to assess the protector role of fosfobion- an energising compound-against the structural lesions of the myocyte.

The influence of age on the thermal transition of serum albumine in rats.

Serum albumine from rats at different ages (1, 3, 9, 18 months) undergoes a thermal reversible denaturation in the range of 40-53 degrees C. Thermal transitions of unbuffered solution of native protein show a significant change of pH as they became heat denaturated. The protein molecule has been analysed in melting studies, manifested by cooperative dissociation of protons and it experiences a decrease in temperature transition with the younger the rats.

Research on some metabolic and enzymatic modifications in experimental hypertensive myocardium.

This paper presents our research on metabolic and enzymatic changes in the experimental, Isoproterenol-induced (ISO) hypertensive myocardium of rats. We analyze the effects produced by the simultaneous administration of adenosinetriphosphate (fosfobion) (FOS) and Isoproterenol on the changes in the body weight/heart weight ratio, and on the biochemical changes of cardiac metabolism. We studied the following parameters in the myocardium tissue and blood: plasmatic and tissular creatinin-phosphokinase, Na+K+ ATP-ase in the sarcolemma and the sarcoplasmic reticulum, Ca+2 ATP-ase in the mitochondrial membrane, sarcoplasmic reticulum and sarcolemma, as well as plasmatic and tissular lactate.