Effect of the antioxidant dibunol and its combination with phenazepam on the behavior of rats in a conflict situation

The influence of dibunol, phenazepam used alone and combined on rat conflict behavior and rat blood and brain malonic dialdehyde content was studied. It was shown that dibunol exerts an unmarked anticonflict action that can be removed by bicuculline. Combined administration of dibunol and phenazepam potentiates appreciably the anticonflict effect. This permits reducing the doses of the drugs. The anxiolytic effect of dibunol alone and combined with phenazepam is attended by a decrease in the content of malonic dialdehyde in rat blood and brain, evidence of the reduction of the lipid peroxidation intensity.     

Effect of chronic alcoholism on the state of the microcirculatory bed of the myocardium

Ultrastructure of myocardial capillaries of rats was studied in cases of chronic alcohol intoxication, experimental alcoholic cardiomyopathy (ACM) and its correction with antioxidants (vitamin E, dibunol). Alterations in the microcirculatory bed were similar in all groups of animals irrespective of disturbances in cardiomyocytes. Cardiomyocyte ultrastructure was improved after treatment with antioxidants, but capillary bed was the same as in untreated animals. High dibunol doses caused the onset of perivascular sclerosis. Disturbances in the microcirculatory bed are, probably, the first step in the determination of ACM pathogenesis and therapy of ACM must be directed at the correction of both alterations of cardiomyocytes and capillary bed.     

Effect of dibunol and isoptin on the creatine kinase and myoglobin content of the blood serum in dogs undergoing postischemic coronary reperfusion

The effect of an antioxidant dibunol and calcium antagonist verapamil on postperfusion release of myoglobin (Mb) and MB-creatine kinase (MB-CK) has been assessed in 30 dogs with experimental coronary occlusive myocardial infarction. It has been shown that reperfusion after 3-hour ischemia does not only accelerate the release of intracellular proteins, but also leads to pronounced myoglobinemia and blood enzymes. In postischemic blood flow recovery with combined dibunol and verapamil preliminary injections, an almost threefold decrease in MB-CK and Mb blood content, as compared to "reperfusion" indexes, was observed by the 10th minute of reperfusion.     

Significance of sarcolemma damage in the pathogenesis of myocardial ischemia induced by pituitrin-isadrin and its correction using the antioxidant dibunol

The elevation of cardiomyocyte membrane permeability has been demonstrated during pituitrin-isadrin-induced myocardial ischemia. Preventive 7-day oral administration of an antioxidant dibunol (30 and 120 mg/kg) preserved sarcolemmal integrity, decreased myocardial membrane permeability to sulfacetamide sodium, and reduced peroxide and mechanical erythrocyte hemolysis. Inhibition of lipid peroxidation with an antioxidant dibunol improved myocardial injury and decreased the death rate of animals with catecholamine-induced myocardial ischemia. These data suggest the involvement of lipid peroxidation in the development of ischemic myocardial injury.     

Effect of the antioxidant dibunol on the course of a neurodystrophic process in the rat pancreas

In experiments on rats using histochemical methods it was postulated that injection of dibunol (ionol) in conditions of subdiaphragmatic vagotomy has a correlative effect on neurodystrophic process in pancreas during the time of observation (7, 14, 30 days postoperation).     

Limited area of coronary-occlusion myocardial infarct in rats undergoing antioxidant therapy

The synthetic antioxidant dibunol, (ionol. 2,6-ditret-butyl-4-methylphenol) produces the limitation of the zone of the coronaro-occlusion myocardial infarction in rats by 15.8 and 24.2% on day 7 during daily oral administration in doses of 80 and 120 mg/kg, respectively. In the doses used, dibunol reduces the activity of glutathione peroxidase but does not change the activity of glutathione-S-transferase and superoxide dismutase in the infarction zone of the myocardium. It is concluded that free radical products play an important role in ischemic and infarction damage to the myocardium.     

Effect of subchronic administration of phenazepam and synthetic antioxidants on the functional status of synaptic membranes in the cerebral cortex of rats subjected to prolonged stress

Monoamine oxidase activity, lipid peroxidation and membrane structure were tested after chronic stress and 7-day treatment with drugs in the brain cortex synaptosomal membranes of rats. The most potent corrector of stress-induced changes, as compared to hydrophobic antioxidant dibunol and tranquilizer phenazepam, was compound 3-OP, a hydrophilic antioxidant.     

Antioxidant ionol suppresses ACTH-dependent secretion of corticosterone

It has been shown that the preliminary administration of a synthetic antioxidant ionol (dibunol, BHT) prevented to a considerable extent the increase in the concentration of corticosterone in the adrenal glands and blood plasma induced by ACTH administration or emotional-painful stress.     

Mechanism of the development of thioridazine retinopathy

Comparative electron microscopic, electrophysiological and biochemical studies of thioridazine influence on lipid peroxidation in vivo (rats, rabbits) and in vitro (model systems) were performed. It was shown that thioridazine retinopathy was not followed by an increase in lipid peroxidation and antioxidant (dibunol) failed to protect the retina against the destructive action of thioridazine. Moreover, thioridazine inhibited lipid peroxidation in model system.     

New paths in the pathogenetic correction of hemic hypoxia]

It is stated that prophylactic administration of ional (dibunol) and taurine to rats exerts an antihypoxic effect in case of acute hemic hypoxia. It is expressed in a decrease of methemoglobin level in blood, increase of pO2, in the skeletal muscles, normalization of the structure of hematoparenchymatous barriers, prevention or decrease in a fall of the rate of oxygen consumption by tissues.     

A histochemical analysis of the enzymes of the enterocyte transport and bioenergetics in rat small intestine after vagotomy and dibunol administration

It was shown that the vagotomy leads to the elevation of the activity of alkaline phosphatase (AP) 7 days after the operation and to the decrease of its activity 30 days after the operation, and to the decrease of the activity of succinic dehydrogenase (SDG) 7 and 30 days after the operation. Introduction of dibunol leads to normalization of these disturbances of the activity of AP and SDG induced by vagotomy.     

Effect of the antioxidant dibunol on the electron paramagnetic resonance signals in the tissues of rats of different ages

Changes in the intensity of EPR signals from the skeletal and heart muscles, liver, kidneys, thyroid, adrenal cortex, and blood were studied in relation to the animals age and the effect of the antioxidant dibunol. Essential changes were revealed in metabolic activity of the majority of the tissues under study as early as within the first 6 hours after antioxidant administration.     

Effect of synthetic phenol antioxidants on the parietal pH value of the gastrointestinal tract in intact and vagotomized rats

The influence of synthetic phenol antioxidants dibunol and BH-3 on the value of parietal pH has been studied in the stomach, duodenum, jejunum, ileum, caecum and rectum of intact and vagotomized rats 1, 7, 14, 30 and 60 days after treatment. It was shown that vagotomy leads to an increase in the stomach pH and to a decrease in pH in other parts of the gastrointestinal tract. Maximum BH-3 doses lead to pH increase in the stomach of intact rats. Chronic administration of therapeutic drug doses does not change pH value in control and vagotomized animals.     

Effect of ethanol and the catalase inhibitor aminotriazole on lipid peroxidation in the rat myocardium

The influence of chronic alcohol consumption and catalase inhibitor aminotriazole administration on the level of nonenzymatic lipid peroxidation has been studied in the rat myocardium. It was demonstrated that combined as well as separate treatment with ethanol or aminotriazole elevated the levels of chemiluminescence and enhanced the rate of accumulation of thiobarbituric acid-reactive products in the nuclei-free and total particulate fraction of the rat heart homogenate. The most pronounced effect was noted during combined application of ethanol and aminotriazole. The induction of chemiluminescence by ethanol was prevented by addition of natural (vitamin E, reduced glutathione) or artificial (dibunol) antioxidants into the incubation media. A putative role of the myocardial catalase-containing micro-peroxisomes in stimulation of the intracellular lipid peroxidation is discussed.     

Effect of stress and the antioxidant ionol on the biosynthesis of catecholamines and the content of dopamine in the heart and adrenal glands

The effects of a synthetic antioxidant ionol (dibunol) on the biosynthesis and content of catecholamines in the heart and adrenal glands were studied. It was shown that in stress a mobilization of catecholamine reserve is combined with a considerable increase in dopamine concentration. In conditions of physiological rest, ionol did not affect the studied indices of adrenal catecholamine biosynthesis, while in the heart it enhanced the dopamine synthesis and content. With ionol administration, stress did not suppress but, on the contrary, increased the neuronal uptake and noradrenaline biosynthesis, catecholamine concentration remaining practically unchanged. Simultaneously, a manyfold increase in the biosynthesis along with a considerable increase in the concentration of dopamine developed in both organs. The data obtained suggest that ionol realizes its stress-defensive effect to a great extent due to the activation of catecholamine biosynthesis and to a concomitant increase in dopamine accumulation.     

Polymorphism of a tumor ce-l population and selection processes. IV. The effect of dibunol and nitrosourea on the variability of Ehrlich-I. Ch. Ph. ascitic strain tumor cells]

A study was made of the effect of dibunol and methyl-N-nitrosourea (MNU) on two tumor cell subpopulations of the Ehrlich-I. Ch. Ph. ascites strain, one of which is characterized with A + B + 2C and A + D + 2C--markers and the other one--with A1 + A2 + 2B + D + C markers. Dibunol that belongs to the class of inhibitors of free-radical processes was shown to bring about changes in cell subpopulations, the mode of changes depending on the dose and regime of treatment. The effect of MNU on the population resulted predominantly in the accumulation of cells with various chromosome aberrations. At early stages of tumor progression, aberrations were more pronounced in cells with marker chromosome "A" than in the cells with 44 chromosomes and markers A1 + A2 + 2B + D + C.     

The nature of N-terminal signal sequence determines the type of intracellular distribution and effectiveness of export of human growth hormone in Saccharomyces cerevisiae

Various N-terminal signal peptides (SP) were tested to investigate a human growth hormone (hGH) synthesis, processing and intracellular sorting in yeast. Maximal level of hGH was observed in the case when the mature hGH gene was placed under the control of PHO5 promoter. In this case about 90% of hGH was localized in the cytosol, but some portion was trustworthly detected in microsomes and periplasma in spite of the absence of SP. Addition of own or PHO5 SP resulted in lowering of the synthesis and a difficulty in the prehGH processing. In this case the immunoreactive products were localized mainly in periplasma and vacuoles and to a lesser degree in the cytosol. When hGH gene was placed under the control of the yeast MF alpha 1 promoter and alpha-factor preprosegment was used as SP more then a half (67%) of hGH processed correctly was exported in a medium, the rest was detected in vacuole (17%) and periplasma (8%).     

Morphological evaluation of the viability of silicon-lavsan tracheal prostheses

Time course of the healing process in the tracheal wall during silicon-lavsan tracheal grafting was investigated in experiments on 108 dogs with a new model of tracheal prosthesis. The formation of granulation tissue was noted as a result of postoperative inflammatory reaction in the prosthetic area. The tracheal epithelial layer adjacent to the anastomoses was hypertrophic and acquired the features of squamous epithelium. Later, after the implantation the prosthesis was surrounded by a thick fibrous capsula. In anastomoses, at tracheal tissue--implant border there was a poorly expressed inflammatory reaction, which had a local character and was compatible with 3 and more years of life in most experimental animals.     

Diagnosis of Primary Cancer of the Liver

The diagnosis of primary cancer of the liver was reviewed in 75 patients. A definitive diagnosis was made during life in 63% and in a further 20% this condition was suspected though histological confirmation was obtained only at necropsy. The most common presenting complaints were abdominal pain and weight loss and the most frequent findings hepatomegaly and ascites. Less than one-half of the patients were jaundiced and when present it was usually mild. An arterial bruit was heard over the liver in 25% of the patients. A sudden and unexplained deterioration in a patient known to have cirrhosis or haemochromatosis should raise the possibility of a primary hepatic tumour; this occurred in 24% of our patients.Alpha-fetoprotein was found in the serum of 11 out of 18 cases. The presence of a mass in the liver was frequently confirmed by liver scan, portal venography, or hepatic arteriography, but these showed no features diagnostic of a primary tumour. Liver scan also proved useful in localizing the lesion for biopsy purposes. Definitive diagnosis is dependent on the histological demonstration of the features of the tumour. This can frequently be achieved by percutaneous needle biopsy, which was positive in 38 out of 57 patients. Wedge biopsies were positive in a further nine patients.