Effect of Tramadol on Rabbit Uterine Contractile Activity Induced in Late Pregnancy.

Effect of Tramadol infusion (5 mg/ml) on oxytocin-induced uterine contractile activity was studied in chronic experiment on female rabbits with different degrees of biological readiness for parturition. In case of sufficient biological readiness for parturition, Tramadol did not change the number of uterine contractions, but increased the amplitude and duration of each contraction against the background of increased creatine phosphate consumption by the myometrium. At the same time, Tramadol infusion to females without biological readiness for partirition suppressed induced uterine contractile activity by reducing the amplitude of each uterine contraction.

[Effect of delta-sleep inducing peptide on free-radical processes in the brain and liver of mice during various light regimens].

Female SHR mice received 5-days long course of delta-sleep inducing peptide preparation "Deltaran" subcutaneously in daily dose of 5 mkg/mice per 24h under standard light regime (12h light: 12 h darkness) or constant illumination. Free-radical level and antioxidative activity in brain and liver was studied by standard methods. Constant illumination increased chemiluminescence in brain by 20 % and decreased liver glutationperoxidase activity by 60 %, as compared to the mice kept in standard light regime. In conditions of standard light regime deltaran increased levels of general antioxidative activity in brain by 9%, liver superoxide dismutase by 17% and lowered levels of glutationperoxidase of liver by 82%. In conditions of constant illumination Deltaran lowered levels of chemiluminescence in liver by 23%, raised the general antioxidative activity in liver by 19% and lowered levels of glutationperoxidase of liver by 69%. It was supposed that deltaran has an antioxidant effect under constant light regime.

[Stress, aging, hypothalamic-pituitary-adrenal axis and reliability of antioxidant enzyme defence].

The purpose of the investigation was to study age-related changes in reaction of the hypothalamic-pituitary-adrenal axis and erythrocyte antioxidant enzyme system in response to acute psychoemotional stress in non human primates. Ten young (6-8 years) and ten old (20-26 years) healthy female rhesus monkeys were subjected to acute moderate psycho-emotional stress (two hours squeeze cage restraint) at 15:00 h. Plasma cortisol (F), activities of superoxide dismutase (SOD), glutathione peroxidase, gluthatione reductase (GR), gluthatione-S-transferase, and lipid peroxidation products (TBARS) in erythrocytes were measured before stress and 30, 60, 120, 240 min and 24 h after beginning of the stress. In young monkeys SOD activity decreased in response to the stress while it increased in the half of old monkeys. Young animals also demonstrated essentially higher increase in plasma F level and GR activity in response to the restraint, in comparison with old monkeys. Level of TBARS did not change in response to the stress in young animals and significantly increased in old monkeys. The age-related alterations in F, SOD, and GR stress responsiveness lead to activation of peroxide oxidation of lipids that may be considered as an important factor of aging damage of erythrocyte functioning and reliability of oxygen transport to tissues under stress conditions.

QSAR studies and antimicrobial potential of 1,3-thiazolylphosphonium salts.

The regression QSAR models were built to predict the antimicrobial activity of new thiazole derivatives. Compounds with high predicting activity were synthesized and evaluated against Gram-positive and Gram-negative bacteria and fungi. 1,3-Thiazole-4-ylphosphonium salts 4 and 5 displayed good antibacterial properties and high antifungal activity. The predictions are in a good agreement with the experiment results, which indicate the good predictive power of the created QSAR models.

Melatonin increases both life span and tumor incidence in female CBA mice.

From the age of 6 months until their natural deaths, female CBA mice were given melatonin with their drinking water (20 mg/l) for 5 consecutive days every month. Intact mice served as controls. The results of this study show that the consumption of melatonin did not significantly influence food consumption, but it did increase the body weight of older mice; it did not influence physical strength or the presence of fatigue; it decreased locomotor activity and body temperature; it inhibited free radical processes in serum, brain, and liver; it slowed down the age-related switching-off of estrous function; and it increased life span. However, we also found that treatment with the used dose of melatonin increased spontaneous tumor incidence in mice. For this reason, we concluded that it would be premature to recommend melatonin as a geroprotector for long-term use.

Disturbances of diurnal rhythms of biogenic amines contents in hypothalamic nuclei as an evidence of neurotropic effects of enterotropic carcinogen 1,2-dimethylhydrazine.

OBJECTIVES: Our data on the contents of norepinephrine (NE), dopamine (DA) and the metabolite of serotonin 5-hydroxyindoleacetic acid (5-HIAA) measured in the suprachiasmatic nuclei (SCN), preoptic area (PA) and median eminence (ME) of hypothalamus of rats after single subcutaneous injection of 1,2-dimethylhydrazine (DMH) as well as the effect of this carcinogen on formation of reactive oxygen species (ROS) in the PA are presented in this paper. RESULTS: Diurnal changes of DA in all studied brain structures and of NE in the PA have been observed in the control group. Their morning levels were higher than evening ones. Rhythms of 5-HIAA in the SCN and diurnal changes of ROS formation have been shown to have contrary changes in control. Both the morning (11 a.m.) and evening (11 p.m.) subcutaneous administration of DMH at the dose of 21 mg/kg of body weight resulted in changes of all rhythms observed in control. In some cases a phase shift was found, in others the rhythms of neurotransmitters and ROS formation disappeared entirely. CONCLUSION: The data obtained confirm the idea of dopaminergic and serotoninergic systems taking part in mechanisms of a response of the hypothalamic nuclei to non-photic stimuli. It is suggested that the effect of DMH on the content and diurnal rhythms of neurotransmitters in the hypothalamic structures under study is due to its affecting activities of the enzymes of biogenic amines synthesis, synaptic transmission, melatonin synthesis and secretion rhythms. The change in ROS formation that is caused by administration of DMH is likely to be due to a disturbance of diurnal rhythms of neurotransmitters that are one of the sources of formation of free radicals in the brain.

The effects of thyroxine isomers on free-radical oxidation processes in subcellular fractions of rat cerebral cortex.

Measurements made by chemiluminescence (CL) were used to estimate effective D- and L-thyroxine concentrations and to study their effects on free-radical oxidation processes in the mitochondrial and synaptosomal fractions of rat cerebral cortex in vitro. These experiments showed that in a model system containing riboflavin, the antioxidant activity of D-T4 was 2.2 times greater than that of L-T4. The effective concentrations for the two forms of thyroxine were I50 = 74.3 +/- 7.1 microM for D-T4 and I50 = 154.7 +/- 12.3 microM for L-T4. Studies of the in vitro effects of thyroxine on the membrane fraction of the cerebral cortex were based on luminol-dependent peroxide CL. At physiological concentrations (10 nM), both isomers of the hormone had identical antioxidant activities, which were stronger in the mitochondrial traction, where the intensity of CL decreased by 69% and 66%, compared with 45% and 46% decreases in the synaptosomal fraction. Since the D-form has no hormonal activity, it is suggested that this effect is associated with the phenolic nature of thyroxine.

[Effect of irradiation from a personal computer video terminal on estrus function, melatonin level, and free radical processes in laboratory rodents]. / Vliianie oblucheniia videoterminalom personal'nogo komp'iutera na éstral'nuiu funktsiiu, uroven' melatonina i svobodnoradikal'nye protsessy u laboratornykh gryzunov.

Chronic irradiation by the video terminal of a personal computer leads to the acceleration of sexual maturation and premature termination of the reproductive function, decreases the nocturnal level of melatonin, the content of diene conjugates and schiff bases in blood serum of female rats and does not affect the intensity of blood serum chemiluminescence in male rats. The data obtained indicate that the irradiation by the personal computer video terminal has a marked biological effect and may affect adversely the health of users.

[Hemodynamic and metabolic effects of adenosine in experimental myocardial infarction]. / Gemodinamicheskie i metabolicheskie éffekty adenozina pri eksperimental'nom infarkte miokarda.

Adenosine, administered intravenously (0.25 mg/kg-1/min-1) to rabbits with experimental myocardial infarction, produced a drop in arterial pressure and total peripheral resistance, normalized stroke volume, increased ATP content at the margin of the infarcted area, and reduced LDG activity and increased SDG activity in the ischemized region.

[Adenosine pharmacokinetics in rats]. / Farmakokinetika adenozina u krys.

The pharmacokinetics of the effective peripheral vasodilator adenosine in blood serum of rats was studied after its intravenous injection. The dynamics of labeled adenosine in blood was described by means of a one-compartment mathematical model. The pharmacokinetic parameters of the drug were calculated from the model coefficients. The distribution of the label of adenosine and its metabolites in blood serum and heart, liver, and kidney tissues was studied by thin-layer chromatography.

[Nitrogen metabolism of Streptomyces antibioticus on media with various glucose contents]. / Azotnyi metabolizm Streptomyces antibioticus na sredakh s raznym soderzhaniem gliukozy.

The dynamics of the glutamine synthetase and glutamate dehydrogenase activity was studied during cultivation of Str. antibioticus on media with different contents of glucose and ammonium sulfate. No correlation between the enzymes activity and the levels of oleandomycin production by the mycelium was observed. It was shown that the levels of oleandomycin biosynthesis repression by glucose did not depend on ammonium sulfate concentration in the medium.

[The effect of guanosyl-5'-monophosphate on metabolic processes in rats with experimental myocarditis]. / Vliianie guanozin-5'-monofosfata na protsessy metabolizma u krys s éksperimental'nym miokarditom.

Ten days course of 5'-GMP intramuscular administration at a dose of 25 mg/kg into rats with adrenaline-produced myocarditis led to normalization of NAD content in myocardial tissue which contributed to restoration of NAD-dependent isocitrate dehydrogenase activity. During the 5'-GMP administration content of ATP and creatine phosphate was kept at the same low level as compared with controls, while restoration of glycogen content was retarded in the heart muscle. Activity of lactate dehydrogenase and lactic acid content were not altered. The decrease in content of pyruvic acid detected in response to 5'-GMP administration may occur due to elevated decarboxylation of pyruvate as a result of NAD content increase in heart muscle.

[Free radical oxidation in placental tissues in preterm delivery]. / Svobodnoradikal'noe okislenie v tkaniakh posleda pri nedonoshennoi beremennosti.

A rate of luminol-dependent chemoluminescence was studied in placental tissues and membranes of premature fetuses (32-36 weeks). Stimulation of free radical oxidation in peripheral parts of placenta and its decrease in ruptures of fetal membranes appear to be among the pathogenic factors responsible for preterm labour. These impairments were accompanied by dissimilar alterations in content of lipid peroxidation products -- diene conjugates and malonic dialdehyde. Possible importance of free radical-dependent protein modification in development of the pregnancy pathology studied is discussed.

[Myeloperoxidase in the human placenta at preterm labor]. / Mieloperoksidaza v platsente cheloveka pri prezhdevremennykh rodakh.

In the present study the level of myeloperoxidase in the human placenta at premature was investigated. Mycloperoxidase content did not depend on its localization in placenta and decreased at premature labour. It is suggested that the decrease in the myeloperoxidase content in placenta results in the weakening of antimicrobial barrier in the system mother-placenta-fetus and plays an important role in pathogenesis of premature delivery at later term.

[Free-radical processes in blood serum, liver and large bowel during 1,2-dimethylhydrazine-induced carcinogenesis in rats]. / Svobodno-radikal'nye protsessy v syvorotke krovi, pecheni i tolstoi kishke pri kantserogeneze, indutsiruemom 1,2-dimetilgidrazinom u krys.

Rats were injected 21 mg/kg dimethylhydrazine (DMH), in a single dose, subcutaneously (experimental run I), or 5 times at weekly intervals (experimental run II) to measure free-radical process indices in blood serum, liver and large bowel 24 hr after a single exposure and 6 months after 5 exposures. Run I identified marked DMH inhibition of blood-serum level of active forms of oxygen (AFO). However it did not involve any changes in the concentrations of such products of lipids peroxidation (LP) as dien conjugates, Schiff's bases and protein peroxides (PP). Neither did total antioxidation activity (TAA) or that of Cu, Zn-superoxydismutase (SOD) change. However, nitrite levels increased while those of ceruloplasmin decreased significantly. AFO levels also dropped in the liver, following a single injection of DMH, with TAA and SOD activity decreased significantly. No changes were observed in AFO generation processes in the bowel which was targeted by DMH treatment. A slight decrease in TAA, a rise in PP and diverse changes in the enzymatic system of antioxodation protection were recorded: decreased SOD activity and an insignificant rise in catalase level (like in the liver). Run II showed an intensification of peroxidation in blood serum and bowel in animals bearing intestinal tumors. However, no distinct changes occurred in the liver. The results point to a tendency of free-radical processes being intensified during DMH-induced carcinogenesis in rats.

[The effect of melatonin on the indices of biological age, on longevity and on the development of spontaneous tumors in mice]. / Vliianie melatonina na pokazateli biologicheskogo vozrasta, prodolzhitel'nost' zhizni i razvitie spontannykh opukholei u myshei.

Fifty female CBA mice were given melatonin with drinking water (20 mg/l) for 5 consecutive days monthly, beginning from the age of 6 months, until natural death. Another 50 intact mice were used as controls. Melatonin failed to significantly influence body weight or food consumption. Age-related switching-off of estrus function was delayed, body temperature decreased. Somewhat decreased motor activity did not affect physical one or endurance. Increase in life span led to higher spontaneous tumor incidence. Another experiment using 20 animals of the same line showed melatonin to inhibit free-radical processes. A conclusion was drawn that caution should be exercised before melatonin is recommended for long-term administration as a geroprotector.

[Effects of hyperbaric oxygenation on free radical oxidation and antioxidant system of blood in the newborn who had acute hypoxia at birth]. / Vliianie giperbaricheskoi oksigenatsii na svobodnoradikal'noe okislenie i antioksidantnuiu sistemu krovi novorozhdennykh detei, perenesshikh ostruiu gipoksiiu pri rozhdenii.

Hyperbaric oxygenation (HBO) was added to the complex of intensive care for 14 full-term newborns born asphyxiated and with cerebral circulation disorders of the I-II degree. Study of the antioxidant enzymatic system and free-radical oxidation by chemiluminescence showed no changes in superoxide dismutase and catalase and a 1.6-2 times increase in the activity of glutathione peroxidase, on the one hand, and an appreciable decrease of free radical processes, on the other. This permitted a conclusion about the absence of toxic effects during HBO and on its membrane-stabilizing action.

[Antioxidant activity of the blood serum in pregnant and nonpregnant women: comparison of various detection methods]. / Antioksidantnaia aktivnost' syvorotki krovi beremennykh i neberemennykhzhenshchin: sravnenie raznykh metodov opredeleniia.

Antioxidant activity (AOA) of the serum was assessed in pregnant and nonpregnant women by three different methods. AOA assessed by the chemiluminescent method with riboflavin was increased in pregnant women (30-39 weeks) in comparison with donors. This increase may be due to appearance of a specific protein component possessing a high AOA in the serum of pregnant women. Measurements of AOA by two spectrophotometric methods, with DPPH and quercetin, showed a decrease of AOA in pregnancy. Analysis of correlations shows that in donors all the methods used reflect the activities of virtually the same components of antioxidant defense, whereas in pregnant women the composition of the predominant antioxidant components is changed. Hence, application of several methods or measurement of certain components of the antioxidant system is advisable in pregnant women.