Functional changes in rat-liver mitochondria during the early phase of burn injury

Administration of 2-methyl-4-dimethylaminobenzene in the diet (0.1%, w/w) for 85-90 days doubled the content of mitochondria in the livers of rats. The azodye was covalently bound to liver proteins, and about 15% of the amount found in liver was associated with the mitochondrial fraction. Mitochondria isolated from the livers of azodye-fed animals showed drastically lowered ability to oxidize NAD+-linked substrates. The inhibited electron-transfer step was the reduction of ubiquinone. The organelles showed a large increase in succinate oxidase activity. The activity of cytochrome oxidase and the content of cytochrome aa3 were substantially higher in these organelles. Azodye-fed animals showed depressed serum cholesterol concentrations. The content of ubiquinone in liver also registered a small increase.

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Morphological changes of mitochondria and mammalian cells, induced by hypochlorous acid

Proceedings of the National Academy of Sciences of Belarus Biological Series ◽

10.29235/1029-8940-2019-64-2-156-168 ◽

2019 ◽

Vol 64 (2) ◽

pp. 156-168

Author(s):

I. B. Zavodnik ◽

R. I. Kravchuk ◽

T. V. Ilyich ◽

E. A. Lapshina ◽

A. G. Vejko ◽

...

Keyword(s):

Rat Liver ◽

Mammalian Cells ◽

Structural Changes ◽

Hypochlorous Acid ◽

Morphological Changes ◽

Liver Mitochondria ◽

Hill Coefficient ◽

Rat Liver Mitochondria ◽

Apparent Dissociation Constant ◽

Functional Changes

Hypochlorous acid, HOCl, is one of the most powerful biological oxidants and the most important mediator of inflammatory damage of cells and tissues. The purpose of this study was to characterize the morphological features of HOCl – induced oxidative impairment in rat liver mitochondria in vitro and to compare the processes of HOCl-induced oxidation in mitochondria, erythrocytes and B14 cells.HOCl addition (300 μM) to mitochondrial suspension resulted in mitochondrial structural changes with a decrease in the mean total length of the crista and the average number of cristae in one mitochondria with no change in the length of one crista. There was shown a slight decrease in the average cross-sectional area of one mitochondria, mitochondrial profile elongation, an increase in the number of altered mitochondria and the heterogeneity of the population. Simultaneously we observed depolarization of the mitochondrial membrane, the rate and degree of which were determined by the concentration of HOCl. HOCl addition (25–150 μМ) induced lysis of erythrocytes for 60–180 s, which was preceded by a change in the shape and size of cells. The apparent dissociation constant for the HOCl – membrane complex was estimated to be Kd = 140 ± 25 μМ, and the Hill coefficient was to be 2.1. The B14 cell exposure to HOCl (100 μМ) led to a loss of ability to sorb on the substrate, to form associates, and to subsequent shrinkage of cells.Therefore, HOCl caused some morphological (and functional) changes in rat liver mitochondria, which may serve as one of the causes of cell death in inflammatory foci. At the level of the whole cells, the HOCl addition induced lysis of red blood cells and deep damage to B14 cells.

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Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066917 ◽

1971 ◽

Vol 29 ◽

pp. 570-571

Author(s):

E. A. Elfont ◽

R. B. Tobin ◽

D. G. Colton ◽

M. A. Mehlman

Keyword(s):

Chemical Composition ◽

Rat Liver ◽

Future Study ◽

Mode Of Action ◽

Liver Mitochondria ◽

Rat Liver Mitochondria ◽

Effective Inhibitor ◽

Biochemical Effects ◽

Glycerophosphate Dehydrogenase ◽

Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

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