PubMed Health⌕ Search

Biomedical subjects

O Kucera

Publications and source records attributed to O Kucera.

15 recordsLinked to original sources

Protective effect of S-adenosylmethionine against galactosamine-induced injury of rat hepatocytes in primary culture.

The protective effect of S-adenosylmethionine (SAMe) on D-galactosamine (GalN)-induced damage to rat hepatocytes was tested in primary cultures. SAMe at concentrations of 50 and 1000 mg/l significantly reduced lactate dehydrogenase release from cells injured by 40 mM GalN after 24 h of incubation. There were no significant changes in urea production after 24 h among tested groups, including control hepatocytes. Exposure of hepatocytes to GalN leads to 3.5-fold decrease in urea synthesis after 48 h in comparison with control cell cultures. Addition of the highest dose of SAMe (1000 mg/l) into the culture media attenuated this decrease by 180 %. None of the tested doses of SAMe (5, 25, 50 and 1000 mg/l) affected considerably the reduced activity of mitochondrial dehydrogenases. The content of reduced and oxidized glutathione in GalN-exposed cells was diminished to 1.5 % and 16 %, respectively, of the control values after 24 h. Using only the highest concentration SAMe increased significantly these contents. SAMe had no effect on dramatically decreased albumin synthesis. These findings indicate beneficial effect of SAMe, especially of the highest concentration, on GalN-induced toxicity to rat hepatocytes in primary culture. This action of SAMe seems to be associated with reduction of plasma membrane damage and increased synthesis of glutathione.

Animals↗

Tert-butyl hydroperoxide selectively inhibits mitochondrial respiratory-chain enzymes in isolated rat hepatocytes.

Sensitivity of various mitochondrial enzymes to oxidative damage was tested on isolated rat liver hepatocytes permeabilized by digitonin. In permeabilized hepatocytes normal respiratory control values were obtained and mitochondrial membranes remained intact. Respiratory rates of NADH-dependent (glutamate + malate, palmitylcarnitine + malate) and flavoprotein-dependent (succinate) substrates were determined in hepatocytes exposed for 5 min to 0.5-3 mM tert-butyl hydroperoxide before addition of digitonin. Our data showed that oxidation of NADH-dependent substrates is much more sensitive to oxidative stress than oxidation of flavoprotein-dependent ones, evidently due to the modification of iron-sulfur clusters or SH groups in the NADH dehydrogenase enzyme complex (Complex I).

Animals↗

Psychopathology of children with minimal brain injuries.

Children with the syndrome of minimal brain injuries, i.e. with psychic sequelae of a slight, diffuse lesion of the cerebral tissue, suffer from disorders of neural activity on different levels, from "primary disorders" such as of simple motor reactions and sensory defects to the most complicated performances such as speech and concept formation. It is assumed that mild lesions of the reticular formation of the brain stem is the common neurophysiological denominator of the whole syndrome. The psychopathological pictures, however, develop only from the continuous interaction of an organically conditioned state with unsuitable educational methods of the irritated parents and with other pathogenic factors of the external environment. The pictures can be divided into four basic diagnostic groups: behaviour disorders, neurotic manifestations, psychopathic traits, and psychotic manifestations.

Attention Deficit Disorder with Hyperactivity↗