[Effect of GABA and pyracetam on mitochondrial ADP phosphorylation in experimental hypokinesia]. / Vliianie GAMK i piratsetama na sistemu fosforilirovaniia ADP mitokhondrii v usloviiakh éksperimental'noi gipokinezii.

Long-term limitation of motor activity of male rats is accompanied by impairments of mitochondrial ADP phosphorylation in liver and heart. The most significant changes were observed after 15 and 45 days of hypokinesia. Administration of GABA and pyracetam to animals subjected to hypokinesia induced a tendency to "normalization" of ADP phosphorilation processes.

[Effect of GABA and piracetam on on ATPase activity in brain and liver mitochondria in experimental hypokinesis]. / Vliianie GAMK i piratsetama na ATF-aznuiu aktivnost' mitokhondrii mozga i pecheni v usloviiakh éksperimental'noi gipokinezii.

Long-term hypokinesia is accompanied by changes in the activity of Mg(2+) and 2,4-dinitrophenol (DNP)-stimulated ATPases of rat brain and liver mitochondria. These changes are phasic and especially pronounced at periods characterised by most pronounced metabolic alterations Treatment of animals with GABA and piracetam tends to normalise the enzyme activities.

[The effect of GABA and piracetam on the qualitative and quantitative composition of the brain phospholipids in rats under hypokinetic conditions]. / Vliianie GAMK i piratsetama na kachestvennyi i kolichestvennyi sostav fosfolipidov golovnogo mozga krys v usloviiakh gipokinezii.

The influence of hypokinesia on phospholipid composition of the brain tissue was investigated. Hypokinesia was found to cause significant disorders in the phospholipid composition. Changes exhibit a phase character and are more pronounced on the 15-th and 30-th days of hypokinesia. The use of GABA and pyracetam promotes the processes aimed at normalization of the phospholipid metabolism in the brain tissue.

[Changes in beta-N-acetylglucosaminidase activity of blood leukocytes in patients with arterial hypertension]. / Izmeneniia aktivnosti beta-N-atsetilgliukozaminidazy leikotsitov krovi u bol'nykh arterial'noi gipertenziei.

Activities of N-acetyl-beta-D-glucoseaminidase and of its A and B forms were studied in leukocytes of healthy persons and in patients with hypertension, hypertension combined with ischemic heart disease and in patients with ischemic heart disease. In healthy persons activity of the enzyme B form was increased with ageing. In the patients activities of both total N-acetyl-beta-D-glucoseaminidase and of its two forms were decreased. This decrease was especially distinct in the group of patients with hypertension.

[Contractile capacity of isolated flaps from the aorta of rats with stable arterial hypertension caused by the prolonged administration of cerebrosides]. / Sokratitel'naia sposobnost' izolirovannykh loskutov iz aorty krys so stoikoi arterial'noi gipertenziei, vyzvannoi dlitel'nym vvedeniem tserebrozidov.

A study was made of the contractility of smooth muscle cells of abdominal aorta strips of noninbred white rats with stable arterial hypertension induced by protracted intraperitoneal injection of cerebrosides isolated from cattle brain. It was demonstrated that as compared with normotensive animals, smooth muscle cells of the animals' arteries are characterized by the increased influx of extracellular calcium via slow potential-dependent calcium channels and hypersensitivity to noradrenaline and serotonin.

[Effect of glycosphingolipids on erythrocyte Na+,K+-ATPase activity]. / Vliianie glikosfingolipidov na aktivnost' Na+,K+-ATPazy éritrotsitov.

The total fractions of gangliosides and cerebrosides isolated from the tissue of human brain were studied for their effect on the Na+, K+-ATPase activity of native erythrocytes and their membranes. It is shown that gangliosides depending on time of their preincubation with the enzyme preparation and concentration produce both the activating and inhibiting action and cerebrosides--only the inhibiting one. Gangliosides inhibit the transport ATPase activity noncompetitively with respect to ATP and Na+ and competitively--to K+, cerebrosides inhibit it noncompetitively with respect to all ATPase activators.

[Analysis of the membrane effects of gangliosides]. / Analiz membrannykh éffektov gangliozidov.

Gangliosides interact with human serum albumin, inducing conformational changes in its globule. Gangliosides bring about an increase in the binding constant of the fluorescent probe 1-anilinonapthalene-8-sulfonate (ANS) with model phospholipid membranes, a decrease in the rate of pyrene diffusion in liposomes. Gangliosides raise the fluorescence intensity of ANS bound with the erythrocytic membrane as the binding constant of the probe-membrane increases, the fluorescence of tryptophanils of membranous proteins gets intensified, the fluorescence maximum of ANS and tryptophan residues shifts to the short-wave area, and the accessibility of tryptophan residues for NO-3 decreases. At the same time there is a reduction in the efficacy of energy migration from tryptophan to ANS and NAD X H2. The data obtained attest to the capability of gangliosides of influencing the conformation of both the lipid and protein phases of biological membranes.

[Cerebrosides as one of the factors regulating the functional state of the blood-vascular wall system]. / Tserebrozidy kak odin iz faktorov reguliatsii funktsional'nogo sostoianiia sistemy krov'-sosudistaia stenka.

During 4 months rats were given intraperitoneal injections of cerebrosides in a dose of 5 mg/kg bw. The measurements were taken of the arterial blood pressure and the function of blood cells. It has been demonstrated that as compared to the control, the experimental animals showed a significant elevation of the blood pressure, hyperaggregation of platelets and red cells, an increase in the ability of platelets to adhesion. It has been also disclosed that there was a decrease in the time of the occurrence of muscle fatigue and death under stress induced by forced dynamic work. The data obtained are of interest in the aspect of investigating the role played by glycolipids in the pathogenesis of cardiovascular diseases.

[Glycosphingolipid content and beta-galacto- and beta-glucosidase activity of the blood in acute myocardial infarction and postinfarction cardiosclerosis]. / Soderzhanie glikosfingolipidov i aktivnost' beta-galakto- i beta-gliukozidaz v krovi pri ostrom infarkte miokarda i postinfarktnom kardioskleroze.

Content of acid and neutral glycosphingolipids was distinctly higher in blood plasma and cells of patients with acute myocardium infarction as compared with healthy persons. In leukocytes of the patients activity of beta-galactosidase, exhibiting pH optimum at pH 3.6, was decreased with simultaneous activation of beta-galactosidase at pH 5.5 and of beta-glucosidase (at pH 4.0 and 5.5). Content of glycosphingolipids in blood decreased in post-infractional myocardial cardiosclerosis but remained sufficiently high as compared with controls. In the cardiosclerosis activity of beta-galactosidase was increased at pH 3.6 as compared with the acute infarction; this activity was decreased at pH 5.5 Activity of beta-glucosidase at the both pH values (pH 4.0 and 5.5) was decreased down to the normal values.

[Neutral glycolipids of blood in normal state and in hypertension]. / Neitral'nye glikolipidy krovi v norme i pri gipertonicheskoi bolezni.

Neutral glycolipids of blood constituted four main fractions both in healthy persons and in patients with hypertension. An increase in di- and trihexosylceramides in blood plasma and in monohexosylceramides from erythrocytes occurred simultaneously with elevation of total blood glycolipids in hypertension.

[Ion permeability of cerebroside and sphingomyelin bilayer membranes]. / Ionnaia provodimost' bisloinykh membran iz tserebrozidov i sfingomielinov.

Ionic conductivity of bilayer membranes formed of cerebrosides and sphingomeylins isolated from bovine brains and its dependence on medium pH were studied. It was found that conductivity of the membranes from cerebrosides in KC1, CaCl2 solutions is 2-3 orders, and from sphingomyelin 1-2 orders higher than that of bilayers from lecithin and phospholipids. Both in cerebroside and sphingomyelin membranes the conductivity depended on medium pH, unlike the bilayer membranes of the brain and liver phospholipids.

[Certain physical parameters of cerebroside and phospholipid-cerebroside membranes]. / Nekotorye fizicheskie parametry tserebrozidnykh i fosfolipidnykh membran.

Study of some electric properties of bilayer membranes made of cerebrosides and phospholipid-cerebroside mixture has shown that the capacity of cerebroside film is lower than that of lecithin-cerebroside and phospholipid-cerebroside ones (0.22 +/- 0.01 mkf/cm2 and 0.28 +/- 0.01 mkf/cm2 respectively). The membranes had small cation selectivity. It is stated that conductivity of cations of mixed phospholipid-cerebroside membrane is two orders, and of cerebroside three orders higher than that of phospholipid bilayers. Conductivity of the films under study depends on the medium pH. By means of fluorescent probes cerebrosides were found capable of changing the conformation of phospholipid membranes.

[Effect of gangliosides on Na-K-ATPase activity and the conformation of microsomal membranes]. / Vliianie gangliozidov na aktivnost' Na-K-ATF-azy i konformatsiiu mikrosomal'nykh membran.

The effect of gangliosides on the activity of Na, K-ATPase and K-dependent nitrophenyl-phosphatase was studied. Low concentrations of gangliosides proved to activate Na, K-ATPase, and high ones to inhibit it. All the concentrations of gangliosides produced only an inhibitory effect on the K-dependent nitrophenyl-phosphatase. Inhibition of the enzyme by gangliosides is reversible and competitive in respect to K+. Calculation of Hill's coefficient demonstrated that both in case of the activating and of the inhibitory action gangliosides acted allosteric effectors. To ascertain the action mechanism of gangliosides on the enzyme their effect on the microsomal membranes was studied by the fluorescent probe method. Gangliosides were found to produce marked conformation shifts in the membranes of the brain microsomes.

[Effect of papaverine on H+ transport in suspension of cat brain mitochondria]. / Vliianie papaverina na transport H+ v suspenzii mitokhondrii mozga koshek.

The intravenous administration of papaverin (3 mg/kg) under conditions of acute experiments showed that it is able to induce a considerable increase in intensity of H+ release from mitochondria of the cat brain tissue cells. Taking into consideration the data of previous researches testifying to the fact taht under the papaverine influence there occurs H+ accumulation in cells due to metabolism intensification, it may be suppose that an intensified release of H+ from the mitochondria plays a definite role in vasodilation of the brain by stimulation of the vessels H+-sensitive receptors.

[Effect of cerebrosides on the oxidative phosphorylation and translocation of hydrogen ions in the brain and liver mitochondria of rats]. / Vliiani tserebrotsidov na okislitel'noe fosforilirovanie i translokatsiiu ionov vodoroda v mitokhondriiakh mozga i pecheni krys

Oxidative phosphorylation and translocation of hydrogen ions in the brain and liver mitochondria of albino rats were studied as affected by cerebrosides with their chronic intraperitoneal injection. Cerebrosides are shown to inhibit the rate of respiration in the brain and liver mitochondria with the presence of ADP as well as that of substrate respiration in the liver mitochondria. A decrease in the phosphorylation rate is observed in the brain and liver mitochondria. When studying kinetics of hydrogen ions translocation in the brain and liver mitochondria it was found out that fixation of hydrogen ions induced by ADP is unchanged quantitatively though the fixation time is prolonged. Release of hydrogen ions under the effect of CaCl2 decreases in the liver mitochondria.