[Glutathione redox system, immune status, antioxidant enzymes and metabolism of purine nucleotides in hypothyroidism].

The immune status, components of the glutathione redox system, the activity of antioxidant enzymes and metabolism of purine nucleotides have been investigated in animals with experimental hypothyroidism. On day 8 after an increase in the number of leukocytes, lymphocytes, T-helpers and T-suppressors as well as increased number of B-lymphocytes was found in blood of thyroidectomized rats. This was accompanied by decreased activity of adenosine deaminase (AD), AMP-deaminase (AMPD), and 5'-nucleotidase (5'N) in blood, but the ratio of enzyme activity AD/AMPD increased. These changes in the activity of enzymes, involved in purine catabolism can be regarded as increased functional relationships between T and B lymphocytes in hypothyroidism. The functional changes of immune system cells were accompanied by increased activity of glutathione peroxidase (GPx), a decrease in the activity of superoxide dismutase (SOD), glutathione reductase (GR) and the ratio GH/GPx. Thyroidectomized rats had increased amounts of total, oxidized (GSSG) and reduced glutathione (GSH), but the ratio GSH/GSSG decerased as compared with control animals. In the liver, hypothyroidism resulted in activation of SOD, GPx, decreased activity of GR and decreased ratio GR/GPx. At the same time, the levels of total, oxidized, and reduced glutathione increased, but the ratio GSH/GSSG as well as activities of enzymes involved in purine nucleotide metabolism ratio (and their ratio 5'N/AD + AMPD) decreased. All these data suggest a functional relationship of the glutathione redox system not only with antioxidant enzymes, but also activity of enzymes involved purine nucleotide metabolism and immune status.

[Changes in the oxidation-reduction system of glutathione--glutathione reductase [NAD(P). H] in the blood and tissues of white rats exposed to high and low temperatures]. / Izmenenie sostoianiia okislitel'no-vosstanovitel'noi sistemy glutation-glutationreduktazy[NAD(P). H] v krovi i tkaniakh belykh krys pri deistvii vysokoi i nizkoi temperature.

The content of different forms of glutathione and the NADPH-dependent glutathione reductasa activity in blood, brain, liver and sceletal muscle of the white rats exposed to low and high temperatures have been investigated. It was shown that in general cooling of animals the amount of glutathione in blood, brain and liver increases, the glutathione reductasa [NAD(P)H] activity decreases. Under super-heating conditions concentration of all forms of glutathione in blood and tissues and the glutathione reductasa activity reduce. Data obtained permitted to assume the considerable role of the changes of the glutathione-glutathione reductasa system state in the realization of temperature factors action.