ABSTRACT
We studied the respiratory activity of mitochondria in peripheral blood leukocytes from 36 patients with coronary heart disease (CHD) and a history of ventricular tachyarrhythmias required cardioverter-defibrillator implantation. The measurements were carried out in incubation buffers with different oxidation substrates (succinate and pyruvate-malate mixture). In pyruvate-malate incubation buffer, oxygen consumption rate and respiratory control coefficients in patients with triggered device did not differ significantly from those in patients without cardioverter-defibrillator triggering. At the same time, respiratory control coefficients were below the reference values. In succinate buffer, values of mitochondrial parameters were significantly lower in patients with triggered devices. Our findings indicate that mitochondria of patients with non-triggered cardioverters-defibrillators have better functional and metabolic plasticity. It was concluded that activity of respiratory processes in mitochondria could be an indicator that should be taken into the account when assessing the risk of developing ventricular tachyarrhythmias.
Subject(s)
Coronary Disease , Defibrillators, Implantable , Oxygen Consumption , Humans , Male , Middle Aged , Coronary Disease/physiopathology , Coronary Disease/therapy , Oxygen Consumption/physiology , Female , Mitochondria/metabolism , Aged , Tachycardia, Ventricular/physiopathology , Tachycardia, Ventricular/therapy , Pyruvic Acid/metabolism , Succinic Acid/metabolism , Malates/metabolism , Mitochondria, Heart/metabolismABSTRACT
Regenerative processes in the liver were studied in 3-month-old (young) and 9-month-old (aged) male Wistar rats on day 1 after 30 and 70% hepatectomy. Regardless of the resected liver volume, shifts in the biochemical parameters of the serum in aged rats were more pronounced than in young animals. After 30% hepatectomy, no age differences in the rate of hepatic regeneration were found, while after 70% liver resection this parameter was higher in young rats. Hepatectomy in young rats led to recruitment of MSC, hepatocyte precursors, endothelial and epithelial progenitor cells into the liver parenchyma and increased fluidity of the plasma and mitochondrial membranes of hepatocytes. In aged rats, the recruitment of MSC, hepatocyte precursors, and endothelial progenitor cells into the injured liver was impaired and the rigidity of the mitochondrial membranes of hepatocytes increased.
Subject(s)
Hepatectomy , Liver Regeneration , Rats , Male , Animals , Rats, Wistar , Liver/surgery , HepatocytesABSTRACT
We studied respiratory activity and microviscosity of mitochondrial membranes from the left ventricular myocardium of 2-month-old (n=8) and 15-month-old (n=8) rats. The respiratory control (RC) during substrate phosphorylation was calculated as the ratio of oxygen absorption rates in the presence of ADP and after its utilization. In 2-month-old rats, RC was 4.66 (4.56; 4.71); in 15-month-old animals, it was significantly (Ñ<0.05) lower: 3.57 (3.50; 3.62). Pyrene probe eximerization indices for regions of protein-lipid and lipid-lipid interactions in mitochondria of 2-month-old animals were significantly lower than in the group of 15-month-old rats, which indicated reduced microviscosity of the lipid environment of proteins. Thus, the decrease in RC of mitochondria from the left ventricle of 15-month-old animals and the increase in the microviscosity coefficients of their membranes indicate age-related changes in the structural and functional activity of mitochondria.