Studies on oxyradical, lipid peroxidation, cytochrome C and mitochondrial calcium in myocardium from diabetic rats

Abstract

The present study was undertaken to observe the difference of nitrogen monoxidum (NO), malondialdehyde (MDA), cytochrome C (Cyt-C), nitric oxide synthase (NOS), mitochondrial calcium and superoxide dismutase (SOD) in myocardium between noninsulin dependent diabetes mellitus (NIDDM) rats and normal rats. Methods: Twenty NIDDM rats were made, and 20 normal rats were used as control. The levels of NO, MDA, Cyt-C, NOS, mitochondrial calcium and SOD in myocardial cells from all rats were measured, and histological changes were observed. Results: Compared with control, the levels of NO (2.28±0.40∗ vs 1.81±0.33 μmol/g protein), NOS (0.49±0.09∗ vs 0.39±0.07 U/mg protein), MDA (7.87±0.31∗ vs 7.36±0.53 nmol/mg protein), cytoplasma Cyt-C (3.68±0.17∗ vs 3.25±0.34 g/L) and mitochondrial calcium (2.90±0.35∗ vs 2.47±0.23 μg/L) were higher (NIDDM rats vs control, ∗P<0.05) in the NIDDM rats. But, the levels of mitochondrial Cyt-C (0.19±0.05∗ vs 0.28±0.06 mmol/L) and mitochondrial SOD (0.81±0.21∗ vs 1.18±0.39 U/mg protein) were lower (NIDDM rats vs control, ∗P<0.05) in the NIDDM rats compared with control. Under microscope, myocardium deliquescenced and mitochondria swelled, and inflammatory cell infiltrated in mesenchyma. Conclusions: Oxyradical, lipid peroxidation, Cyt-C and mitochondrial calcium are involved in the damage of myocardium in NIDDM rats.