[Parameters of free radical oxidation in blood plasma of women from the Altai region]. / Pokazateli svobodnoradikal'nogo okisleniia v plazme krovi zhitel'nits Altaiskogo kraia.

We studied the indices of free radical-mediated processes in blood plasma of women from the Altai district affected by the nuclear weapon tests at the Semipalatinsk ground in 1949-1962 and 1965. The data obtained suggest modifications of free radical-mediated processes in inhabitants of the regions most affected by the tests. A significant decrease in the activity of erythrocytic superoxide dismutase indicates structural and functional disturbances of the erythrocytes.

[Generation of superoxide anion and lipid peroxidation in serum of gout patients]. / Generatsiia superoksid-aniona i perekisnoe okislenie lipidov v syvorotke krovi bol'nykh podargoi.

Alterations in content of lipid peroxidation products, reactions of generation/interception of superoxide anion radicals, content of R-proteins and uric acid were studied in blood serum of 83 patients with gout depending on the disease activity. Rates of lipid peroxidation, estimated by content of thiobarbituric acid-positive products, and of superoxide anion generation as well as content of R-proteins correlated distinctly with activity of the inflammation. At the same time, content of uric acid in blood serum of these patients correlated reversely with content of the lipid peroxidation products at the disease preexacerbation period, while concentration of these products depended on content of total iron.

[Characteristics of the effect of 2-pyrrolidone acetamide (piracetam) on energy coupling in rat skeletal muscle mitochondria during cold stress]. / Osobennosti deistviia 2-pirrolidonatsetamida (piratsetama) na énergeticheskoe sopriazhenie v mitokhondriiakh skeletnykh myshts krys v usloviiakh kholodovogo stressa.

Effects of 2-pyrrolidone acetamide (piracetam) on energetic state of mitochondria were studied in skeletal muscles of intact and ovaryectomized rats under conditions of drastic cooling (4 min swimming at 10 degrees). Readministration of piracetam was shown to cause uncoupling of oxidation and phosphorylation in mitochondrial respiratory chain (a decrease in respiratory control by Chance), as well as the drug increased the rate of O2 consumption in presence of oligomycin and decreased the uncoupler stimulating action on respiration in the group of intact animals. The alterations observed were most distinct in rats with cold stress, which was followed by piracetam administration, except of the rate of respiration stimulation, distinctly increased in presence of uncoupler. Piracetam did not exhibit any noticeable effects on the patterns of respiration studied in skeletal muscles of ovaryectomized rats. Protective properties of piracetam in cooling are discussed.

[Mechanism of action of piracetam on NADH oxidation via the external pathway in rat liver mitochondria]. / K mekhanizmu deistviia piratsetama na okislenie NADH po vneshnemu puti v mitokhondriiakh pecheni krys.

Activation of the external pathway (amytalantimycine A-resistant) of the exogenous NADH oxidation was studied in rat liver mitochondria after long-term (within 6 days) administration of pyracetame. Stimulation of lipid peroxidation and a decrease in viscosity of mitochondrial membranes accompanied the increase in the rate of oxygen consumption in mitochondria in presence of the exogenous NADH, amytal and antimycine A.

[Characteristics of the effect of piracetam on liver-mitochondrial respiration in intact and gonadectomized rats of both sexes]. / Osobennosti deistviia piratsetama na dykhanie mitokhondrii pecheni u krys raznogo pola (intaktnykh i v usloviiakh gonadektomii).

It has been established in experiments on rats that subcutaneous administration of piracetam for 6 days in a daily dose of 100 mg/kg produces in intact but not in gonadectomized animals the following alterations in the system of oxidation and energetic coupling of liver mitochondria: a decrease in the magnitude of the respiratory control according to Chance, elevation of the rate of oxidation of NAD+-dependent substrates, a decrease in the stimulation of the rates of substrate oxidation by a disconnector, a rise of the rate of exogenous NADH oxidation by the amytal-antimycin A-resistant pathway. The action of piracetam described is pronounced to a greater degree in females than in males.

[Metabolic state of liver mitochondria and lymphocytes after T-activin administration under condition of hypothermia]. / Metabolicheskoe sostoianie mitokhondrii pecheni i limfotsitov pri vvedenii T-aktivina na fone rezkikh okhlazhdenii.

After 10 days of swimming (10 min per day, water temperature +20 degrees C) the oxygen consumption in rat liver mitochondria increased via the external pathway of NADH oxidation from 3.6 +/- 0.3 to 4.4 +/- 0,2 nmoles O2 x min-1 x mg-1 protein; when the rats were simultaneously injected with an endogenous immunomodulator T-activin (5 micrograms/100 g body weight) daily, this rate increased up to 6.5 +/- 0.6 nmoles O2 x min-1 x mg-1 protein. In the control group, the uncoupled respiration rate is also higher, while the ascorbate+ +TMPD oxidation rate is lower than in the cold- and cold + T-activin-treated groups. The metabolic states of lymphocyte mitochondria did not differ in the three experimental groups. The respiration rates and delta psi m (monitored by diS-C3-(5) fluorescence) of lymphocyte mitochondria in these three groups were also identical.

[Action of 2-pyrrolidone acetamide (piracctam) on the electron transfer respiratory chain in rat liver mitochondria]. / Deistvie 2-pirrolidonatsetamida (piratsetama) na dykhatel'nuiu tsep' perenosa élektronov v mitokhondriiakh pecheni krys.

Repeated administration of 2-pyrrolidone acetamide (pyracetam; a structural analogue of GABA) at a dose of 100 mg/kg led to considerable alteration in systems of oxidative phosphorylation in liver mitochondria of intact rats. These alterations consisted in a decrease in the value of respiratory control when glutamate and malate were used as substrates, an increase in the rate of exogenous NADH oxidation in the amytal-antimycin A resistenant pathway and reduction in concentrations of cytochromes c, c1 and a. These effects were not observed in castrated rats. The effect of pyracetam on respiratory chain of liver mitochondria appears to be realized via regulation of sexual glands functions.

[Activation of the external pathway of NADH oxidation in mitochondria at decreased pH]. / Aktivatsiia vneshnego puti okisleniia NADH v mitokhondriiakh pri snizhenii pH.

The rates of external and internal pathways of NADH oxidation in mitochondria of liver and skeletal muscle and skeletal muscle homogenate were studied at decreased pH and increased concentrations of Pi and CaCl2. The results obtained are indicative of an existence of an external pathway of NADH oxidation, which is insensitive to antimycin A and rotenone in skeletal muscle mitochondria. In the mitochondria of liver and skeletal muscle NADPH does not replace NADH in the external pathway; the NADH oxidation is sensitive to mersalyl and KCN. The decrease of pH of the incubation medium from 7.5 to 6.5 or the increase in Pi concentration up to 8-10 mM activates the external pathway and inhibits the internal pathway in liver mitochondria; the same effect is observed after addition of 10 microM CaCl2, pH 7.2. The external pathway of NADH oxidation in liver mitochondria is sensitive to the inhibitors of phospholipase A2 (nupercaine, EGTA) and the inhibitor of lipid peroxidation (ionole).