Abstract: Experimental ischemia of rat myocardium was accompanied by increase of light sum (S) and maximal intensity (Imax) of chemiluminescence, amount of a malonic dialdehyde and conjugated dienes in cytoplasmic fraction. The activity of NADP-dependent malate dehydrogenase (EC 18.104.22.168; NADP-MDH) was 1.6 times higher in rat heart under ischemia. NADP-MDH was purified from normal and ischemia-exposed rat myocardium. Using NADP-MDH purified enzyme preparations the values if Hill coefficient for oxaloacetate (1.83 ± 0.07 and 1.50 ± 0.10) and Km for NADPH (0.058 ± 0.003 and 0.096 ± 0.004 mM) were determined for the enzyme at norm and under ishemia respectively. Effects of Fe2+, Ca2+, Cu2+ ions, H2O2, oxidized and reduced glutathione, adenine nucleotides influence on functioning of NADP-MDH from rat heart at norm and under ischemic conditions have been investigated.
Reference: Safonova O.A., Popova T.N., Matasova L.V., Artyukhov V.G., Free radical processes intensity and regulation of cytoplasmic NADP-dependent malate dehydrogenase in rat cardiomyocytes at norm and under ischemia, Biomeditsinskaya khimiya, 2005, vol: