scholarly journals The stimulatory effects of carbon tetrachloride on peroxidative reactions in rat liver fractions in vitro. Inhibitory effects of free-radical scavengers and other agents

1971 ◽  
Vol 123 (5) ◽  
pp. 823-828 ◽  
Author(s):  
T. F. Slater ◽  
B. C. Sawyer
Keyword(s):  
Free Radical ◽  
Vitamin E ◽  
Carbon Tetrachloride ◽  
Rat Liver ◽  
Free Radical Scavengers ◽  
Radical Scavengers ◽  
Inhibitory Effects ◽  
Low Concentrations ◽  
Stimulation Of

1. The effects of a number of free-radical scavengers and other agents on the stimulation of malonaldehyde production due to low concentrations of carbon tetrachloride have been studied in rat liver microsome suspensions. 2. Promethazine, propyl gallate and NN′-diphenyl-p-phenylenediamine were extremely active in inhibiting the stimulation of malonaldehyde production due to carbon tetrachloride; inhibitory effects were demonstrable with these agents at 0.1μm. 3. Low concentrations (1–100nm) of vitamin E–polyethylene glycol 1000–succinate increased the stimulation of malonaldehyde production due to carbon tetrachloride, but higher concentrations of the vitamin E preparation decreased both the stimulation due to carbon tetrachloride and the endogenous peroxidation that occurs in the absence of carbon tetrachloride. 4. Other agents tested that were effective in the range 1–20μm in decreasing the stimulation of malonaldehyde production due to carbon tetrachloride were inosine, desferrioxamine and EDTA. Agents tested that were not effective, except at very high concentrations (100μm or greater), were Nupercaine, Cetab and sodium phenobarbitone. 5. The results are discussed in terms of the mechanisms responsible for the observed inhibitions of malonaldehyde production, and of the relevance of the in vitro system to the liver damage produced by carbon tetrachloride in vivo.

scholarly journals Changes in oxygen consumption induced by t-butyl hydroperoxide in perfused rat liver. Effect of free-radical scavengers

1984 ◽  
Vol 223 (3) ◽  
pp. 879-883 ◽  
Author(s):  
L A Videla ◽  
M I Villena ◽  
G Donoso ◽  
C Giulivi ◽  
A Boveris
Keyword(s):  
Oxygen Consumption ◽  
Free Radical ◽  
Oxygen Uptake ◽  
Rat Liver ◽  
Recovery Phase ◽  
Free Radical Scavengers ◽  
Perfused Rat Liver ◽  
Radical Scavengers ◽  
Butyl Hydroperoxide ◽  
Biphasic Effect

The addition of t-butyl hydroperoxide to perfused rat liver elicited a biphasic effect on hepatic respiration. A rapid fall in liver oxygen consumption was initially observed, followed by a recovery phase leading to respiratory rates higher than the initial steady-state values of oxygen uptake. This overshoot in hepatic oxygen uptake was abolished by free-radical scavengers such as (+)-cyanidanol-3 or butylated hydroxyanisole at concentrations that did not alter mitochondrial respiration. (+)-Cyanidanol-3 was also able to facilitate the recovery of respiration, the diminution in the calculated rate of hydroperoxide utilization and the decrease in liver GSH content produced by two consecutive pulses of t-butyl hydroperoxide. It is suggested that the t-butyl hydroperoxide-induced overshoot in liver respiration is related to increased utilization of oxygen for lipid peroxidation as a consequence of free radicals produced in the scission of the hydroperoxide by cellular haemoproteins.

Effects of thyroid hormone on coenzyme Q and other free radical scavengers in rat heart muscle

1995 ◽  
Vol 145 (1) ◽  
pp. 131-136 ◽  
Author(s):  
T Mano ◽  
R Sinohara ◽  
Y Sawai ◽  
N Oda ◽  
Y Nishida ◽  
...  
Keyword(s):  
Free Radical ◽  
Vitamin E ◽  
Heart Muscle ◽  
No Reduction ◽  
Active Oxygen Species ◽  
Coenzyme Q ◽  
Serum Levels ◽  
Organ Damage ◽  
Free Radical Scavengers ◽  
Radical Scavengers

Abstract Active oxygen species are reported to cause organ damage. This study was therefore designed to determine the behaviour of antioxidants and free radical scavengers so as to reveal changes in animals in the hyper- and hypothyroid state. Levels of antioxidant factors (i.e. coenzyme Q (CoQ)10, CoQ9 and vitamin E) and free radical scavengers (catalase, glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD)) were measured in the heart muscles of rats rendered hyper- or hypothyroid by 4 weeks of thyroxine (T4) or methimazol treatment. Serum levels of CoQ9 and total SOD were also measured. A significant reduction in CoQ9 levels was observed in the heart muscles of both hyper- and hypothyroid rats when compared with control hearts. There was no difference in serum CoQ9 levels in thyroid dysfunction when compared with control animals. Levels of vitamin E in the heart muscles of hyperthyroid rats were significantly increased, and there was no reduction in vitamin E levels in hypothyroid rats when compared with control hearts. GSH-PX levels in the heart muscle were reduced in hyperthyroid rats and increased in hypothyroid rats when compared with control hearts. However, there were no differences in catalase levels in heart muscle between hyper- and hypothyroid rats. The concentration of SOD in heart muscle was increased in hyperthyroid rats and was not decreased in hypothyroid rats compared with control rats, suggesting the induction of SOD by excessive production of O2−. These data suggest that the changes in these scavengers have some role in cardiac dysfunction in the hyper- and hypothyroid state in the rat. Journal of Endocrinology (1995) 145, 131–136

Sign in / Sign up

Export Citation Format

Share Document