Specifically reactive cells in experimental allergic pertussis encephalomyelitis]

Dynamics of emergence of specific reactive cell (SRC) with respect to the brain antigen in the draining regional lymph nodes and peripheral blood was studied in experimental whooping cough allergic encephalomyelitis (EAE) in guinea pigs. The greatest number of SRC in the regional lymph nodes, that markedly decreased by the 9th day of sensitization, was revealed in the middle of the EAE incubation period (the 6-7th day), whereas the peripheral blood showed the highest SRC number during this period. The SRC number rose in the regional lymph nodes and dropped in the peripheral blood at the height of EAE progress (the 20th day). It is concluded that SRC found may be attributed to T lymphocyte population.     

The inhibition stage of lipid peroxidation during stress

Stress is shown to induce at first the generalized inhibition of lipid peroxidation (LPO), and then the activation of LPO. In brain and blood serum of rats subjected to continuous footshock as well as to restraint stress LPO products decreased and superoxide scavenging activity increased during the initial period of stress, after 1 hour of footshock LPO indices nearly reached normal values, and after 2 hours of footshock the accumulation of LPO products and decrease of superoxide scavenging activity were seen. LPO inhibition was accompanied by accumulation of easy oxidizable brain phospholipids and by depletion of brain cholesterol, during LPO activation brain cholesterol content and cholesterol-phospholipid ratio increased. The content of LPO products--fluorescent Schiff bases in blood plasma of women suffering from algomenorrhea at first decreased (O-12 h) and then dramatically increased (12-24 h) after a onset of pain at the beginning of menstruation. The data suggest that the stage of LPO inhibition precedes its activation during stress.     

Protective action of antioxidant preparations on the development of experimental allergic encephalomyelitis in guinea pigs

The authors studied the action of combined tocopherol, lithium hydroxybutyrate and pyridoxal phosphate on the development of experimental allergic encephalomyelitis (EAE) in guinea-pigs. The use of the combined drug from the first days of immunization with encephalitis-inducing material prevented the development of EAE, activation of lipid peroxidation (LPO), and the appearance of the blood serum neurotropic activity. Administration of the combined drug starting from the 7th day after immunization appeared ineffective as was the administration of each drug alone, starting from the first days of immunization. The data obtained support an important role of LPO activation for the pathogenesis of the neuroallergic process.     

Lipid peroxidation of rat spleen and thymus lymphocytes treated with x-rays (0-5-1.0 Gy)

It is established, that low doses of X-ray irradiation have affected activation of lipid peroxidation (LPO) in immunocompetent cells of the spleen and thymus. The amount of malonic dialdehyde (MDA) in lymphocytes of spleen and thymocytes increases 2 times twenty-four hours after animals' irradiation by X-rays in a dose of 0.5 Gy; when a dose grows to 1.0 Gy, the MDA content in the spleen lymphocytes increases from the 1st to the 6th days and in thymocytes from the 1st to the 3d days reaching its maximum at the 3d day. MDA accumulation in the immunocompetent cells of irradiated animals varies depending on the method of lipid peroxidation initiation.     

Carnosine prevents the activation of free-radical lipid oxidation during stress

Carnosine (beta-alanyl-L-histidine) injected to intact albino rats (20 mg/kg body weight) induces depletion of lipid peroxidation (LPO) products in brain and blood serum, an increase of superoxide scavenging activity in brain and serum, decrease of cholesterol: phospholipid ratio and increase of easy oxidizable phospholipid portion in brain lipid extracts. After painful stress (footshock during 2 hours) LPO products are accumulated in brain and serum, cholesterol: phospholipid ratio increases and the portion of easy oxidizable phospholipids decreases. Carnosine given before stress prevents LPO activation. Effects of carnosine and stress are not additive: LPO inhibition induced by carnosine is much more in rats subjected to stress.     

Effects of Single and Repeated Footshock on Dopamine Release and Metabolism in the Brains of Fischer Rats

Abstract: Changes in the tissue levels of 3-methoxytyramine (3-MT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and dopamine in the frontal cortex, hypothalamus, nucleus accumbens, and striatum were evaluated after 0.5-4 h of footshock (2 mA, for 3 s every 30 ± 5 s) in Fischer rats. 3-MT, DOPAC, and HVA levels in the four brain areas peaked at 0.5 h and in most cases returned to baseline values within 4 h. No changes were found in dopamine levels. Repeated footshock stress was evaluated by administering 10 footshock sessions (0.5 h, two per day for 5 days). At the end of the 10th footshock session, 3-MT levels were higher than at the end of the first footshock session in three of the four brain regions, indicating sensitization of dopamine release. No differences were found between the first and 10th footshock sessions in DOPAC and HVA levels. Fourteen days after the 10th footshock session, the levels of 3-MT, DOPAC, and HVA were the same as in control rats in all four brain regions. A 0.5-h footshock challenge presented 14 days after the 10th footshock session attenuated DOPAC levels in the hypothalamus and nucleus accumbens. In contrast, DOPAC and HVA levels in the frontal cortex showed sensitization after footshock challenge, and a similar trend was apparent for 3-MT levels. These results indicate that repeated footshock stress induces generalized sensitization of dopamine release and turnover in some areas of the brain of Fischer rats. This sensitization may persist in the cortical but not subcortical dopamine neurons after discontinuation of the treatment.     

Glutathione-deficient state of nervous tissues in starved animals intensifies lipid peroxidation and oxidation of protein SH-groups

The levels of the lipid peroxidation products (LPO), different forms of protein SH-groups and their oxidation rate in the homogenates of the mesencephalon, hypothalamus and sensorymotor cortex of normal and GSH-deficient rats under 3-day food starvation were studied. It was shown, that the basic level of LPO products--lipid hydroperoxides and malonic dialdehyde (MDA) in hypothalamus and sensorymotor cortex of normal animals are by 20-30% (p < 0.05) higher and reduced glutathione (GSH) content is 2 times higher, than these values in mesencephalon. Under 3 day starvation of normal animals activation of the LPO observed only in the hypothalamus and sensorymotor cortex, whereas under 3 day starvation of the GSH-deficient rats formed by the intraparenteraly injection of diethylmaleate in a dose of 2.5 mmol/kg of body weight in all investigated structures the lipid hydroperoxides and MDA increased many times (2-3 times), the content of the surface and masked protein SH-groups decreased and essentially increased the oxidation rate of these functional groups. It was proposed that GSH and its enzymes participate in the LPO regulation and protection of protein SH-groups from oxidative damage at this event the intensity of this prosesse depends on structural and functional organization of nervous tissues.     

Stabilizing effect of hydroxybenzimidazole and its derivatives on biological membranes during activation of lipid peroxidation

Inhibition of lipid peroxidation (LPO) by oxybenzimidazole (OBI) and its derivatives--alkyloxybenzimidazole (AOBI) and alkylethoxybenzimidazole (AEBI) was studied in liver microsomes and brain synaptosomes. It has been shown that both OBI and AOBI strongly inhibit LPO in microsomes and not synaptosomes. AEBI failed to inhibit LPO in microsomes. AOBI is more potent than OBI both in ascorbate- and NADPH-dependent LPO of microsomes. An antioxidant effect of both compounds is more marked in ascorbate-dependent LPO. The investigation of the possible use of AOBI for the protection of liver membranes in various pathological conditions associated with LPO activation seems promising.     

Enhanced erythrocytic lipid peroxides level in rabbits after repeated parental administration of iron

An experiment was conducted in rabbits to evaluate the possible involvement of oxidative stress in iron-overload animals. Ten adult female New Zealand white rabbits were divided into 2 equal groups with 5 animals each. Group II animals received intramuscular iron dextran injections (120 mg/kg body wt/day) on alternate day for 14 days (8 injections), while Group I animals did not receive any iron supplementation to serve as negative controls. The blood samples were collected by cardiac puncture before the start of iron dosing and thereafter, at weekly intervals for 28 days. The samples were processed to measure blood iron concentration, packed cell volume, erythrocytic lipid peroxide (LPO) level, superoxide dismutase (SOD) and catalase (CAT) activities. The blood iron concentration showed a rising trend following repeated iron administration, and the mean level recorded on day 14 was significantly higher than respective day 0 value. LPO level remained significantly higher from day 14 onwards till the end of the observation period of 14 more days after cessation of iron adminstration. Erythrocytic superoxide dismutase activities showed a transient significant rise on day 7, and thereafter, showed a declining trend, but remained statistically comparable to respective day 0 or corresponding value of the control animals.     

Effect of antiserum against isologous aggregated immunoglobulins on the delayed-type hypersensitivity in mice immunized with sheep red blood cells

The mouse antiserum against isologous aggregated immunoglobulins (MAAS) injected to mice sensitized with 10(5) sheep red blood cells (SRBC) did not influence the delayed-type hypersensitivity (DTH) tested on the peak of sensitization (the 4th day) but enhanced significantly DTH tested on the 6th day. MAAS completely abolished the DTH suppression observed after sensitization with 5 x 10(7) SRBC. In transfer experiments the number of the DTH suppressor cells decreased in the spleen of sensitized mice under the MAAS action. MAAS did not affect the proliferation of antibody-forming cells (AFC) and hemagglutinin production but reduced by 70% the number of rosette-forming cells (RFC) in the spleen on the peak of the initial immune response. The data obtained may indicate that RFC participate in DTH suppression.     

Effect of alpha-ketoglutarate on neurobehavioral, neurochemical and oxidative changes caused by sub-chronic cyanide poisoning in rats

Recent studies revealed that alpha-ketoglutarate (A-KG) alone or with sodium thiosulfate (STS) provide significant protection against acute and sub-acute cyanide poisoning in rodents. This study addresses the protective effect of A-KG and/or STS in sub-chronic (90 days) cyanide poisoning. Wistar rats were divided into seven groups (n = 10): Control animals, potassium cyanide (KCN) A-KG, STS, KCN + A-KG, KCN + STS and KCN + A-KG + STS. Spontaneous motor activity and motor coordination were recorded every 15th day. Lipid peroxidation (LPO), reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) in blood, brain, liver and kidney, and glutamate, aspartate and dopamine in discrete regions of brain were measured following 90 days exposure. Cyanide significantly decreased motor coordination, accompanied by increase in LPO (blood, brain and liver) and dopamine (corpus striatum and cerebral cortex) levels, and depletion in GSH (blood, brain and liver), GPx (brain and liver), SOD (brain and liver), and CAT (blood and brain) levels. Although treatment of A-KG and STS alone significantly blunted the toxicity of KCN, concomitant use of both afforded the maximum protection. This study shows a promising role of A-KG and STS as treatment regime for long term cyanide exposure.     

The antiradiation properties of the ecdysteroid-containing compounds

The antiradiation properties of the ecdysteroid-containing preparations ("serpisten" and inokosterone) are studied under their application before or after the 22.6 cGy chronic low intensity gamma-irradiation of mice. It is shown that the antiradiation of these compounds depend on the dose of preparations and time of the application before or after irradiation of mice. "Serpisten" prevented the decrease of the growth of the body mass of irradiated mice. The normalization of the phospholipid composition of the mice liver and blood erythrocytes for the most investigated parameters revealed under the application of this compound at the dose of 50 mg/kg after the irradiation of animals. The capacity of "serpisten" to decompose of peroxides is shown in vitro. Inokosterone had the certain anabolic properties, caused the normalization of the total peroxidase activity of blood and intensity of the lipid peroxidation (LPO) in brain and in liver, and also the repair of the interrelation between the LPO intensity and catalase activity in the irradiated mice liver. The obtained results allow to conclude that the antiradiation properties of the ecdysteroid-containing preparations under the chronic low intensity irradiation of animals at the low dose due to their capacity to depend on the LPO regulatory system parameters.     

Changes in the electroencephalographic and gamma-aminobutyric acid transaminase and succinic semialdehyde dehydrogenase in the allergen induced rat brain

Electroencephalographic activity and gamma-Aminobutyric acid Transaminase together with Succinic semialdehyde dehydrogenase activity changes produced by sensitization with Prosopis juliflora pollen allergen were studied in the cerebral cortex and hypothalamus of the rat brain. Electrical activity of EEG recording begins to appear on 3rd day after sensitization with maximum increase in activity was found on day 9 and decreased after that. A sudden increase in electrical activity was produced in 9th day sensitized rat with 10 min after giving challenging dose intravenously. The measurement of enzymatic activity of GABA-T and SSA-DH showed decrease and increase in 3, 9, 15 and 30 days sensitized rat hypothalamus and cerebral cortex whole homogenate and mitochondrial fractions. A maximum changes in enzymatic activity was found in 9th day sensitized rat with significant alterations after giving sudden stress as challenging dose. These changes in EEG activity and GABA-ergic neurotransmitter in allergenic rats showed the immunoregulatory role of nervous system mediated via GABA shunt.     

Glycosaminoglycans of the aorta in avitaminosis]

It has been shown that pregnancy specific beta 1-globulin (SBG) is found in the rat blood serum on the 6--7th day of pregnancy. SBG reaches the maximum by the end of pregnancy and is not detected already at the 3d--4th day after delivery. The placenta is the site of the SBG snythesis. Other organs of the pregnant rat are not able to incorporate radioactive aminoacids into the protein in vitro.     

Biosynthesis and production of specific beta 1-globulin (SBG) during pregnancy in rats]

It has been shown that pregnancy specific beta 1-globulin (SBG) is found in the rat blood serum on the 5--7th day of pregnancy. SBG reaches the maximum by the end of pregnancy and is not detected already at the 3d--4th day after delivery. The placenta is the site of the SBG synthesis. Other organs of the pregnant rat are not able to incorporate radioactive aminoacids into the protein in vitro.     

Brain monoamines and the hypophyseo-gonadal system of adult rats after the androgenization of their mothers during pregnancy

The brain noradrenaline system and its involvement in the control of the hypothalamic-hypophysial-gonadal complex were studied on 3 month old Wistar rats, which descended from the mothers treated with testosterone propionate on the 16th and 18th day of pregnancy. A season-independent weakening of the activating effect of noradrenaline, introduced into the brain lateral ventricle on the estradiol and testosterone content of the peripheral blood has been shown, compared with the descendants of the mothers treated with oil at the same times of pregnancy. Unlike noradrenaline, the intraventricular introduction of serotonin or dopamine was accompanied by a similar activation of the hypophysial-gonadal system in the descendants from both the androgenized and control mothers. In the descendants from the former, the thermal reaction to the intraventricular introduction of noradrenaline underwent changes as well. A conclusion is reached that testosterone propionate, introduced during the prenatal period, exerts a long-term and to a certain extent, selective and generalized effect on the developing brain noradrenaline system. In the rats, the critical period for the disturbance in androgen balance influence on the noradrenaline mechanisms of brain is timed to no later than the 18th day of prenatal development.     

Role of lipid peroxidation in damage to serotonin receptors and development of epileptiform seizures during hyperoxia

Hyperoxia brought about substantial accumulation of primary and end products of lipid peroxidation (LPO) and a significant lowering of alpha-tocopherol content in rat brain tissues. Preinjection of animals with synthetic and natural antioxidants (4-methyl-2,6-ditretbutylphenol and alpha-tocopherol) prevented LPO activation and decreased the frequency of epileptiform seizures induced by hyperoxia. Administration of a mixture of unsaturated fatty acids led to an opposite effect. The changes in the properties of serotonin receptors were found to be dependent on the hyperoxia-induced LPO. These changes were marked by the reduced specific binding of serotonin with neuronal membranes of the rat brain cortex. The data obtained allowed the conclusion about the key role played by LPO activation in toxic action of hyperbaric activation on the brain.     

Aminopeptidase activity levels during axonal and dendritic growth in the rat brain.

Brain aminopeptidase activity has been suggested as a candidate for the regulation and biotransformation of several neuropeptides. In this paper, changes in Lys- and Leu-aminopeptidase activities in rat brain hemispheres, cerebellum and medulla were examined in 1-, 3-, 5- and 7-days postnatal subjects. Aminopeptidase activities were studied by measuring the rate of hydrolysis of the artificial chromogenic substrates Lys- and Leu-2-naphthylamides (fluorimetrically detected in triplicate). Both enzyme activities show a decrease on the 3rd day of life followed by increases on the 5th and 7th day postbirth. It is suggested that these activities could play a part in the neurochemical changes that take place during axonal and dendritic growth in the rat brain.     

The effect of prenatal stress on activity of the neurosteroids synthesis enzyme in the "critical period" of brain sexual differentiation in male rats

The effect of daily immobillisation stress in female rats on the 15th to 18th days of pregnancy upon synthesis enzyme for neurosteroids of alpha-reductase in their male offspring brain, was studied. A decrease in the enzyme activity in the cortex and hypothalamus of male foetuses occurred within 24 hr following the latest stress, whereas it was increased in the cortex of newborn offspring. An enhancement of the 5 alpha-reductase activity in the cortex, hippocampus and hypothalamus was also found in prenatally stressed males on the 5th day of life. A decrease in the testosterone and progesterone contents in the blood plasma of the animals under study was revealed on the 19th day of their embryonic life as well as in newborn rats, the blood level of progesterone, at that, remained decreased even at the age of 5 days. A possible part ofneurosteroids in action of prenatal stress upon sexual differentiation of the brain is discussed.     

Regeneration of masseter muscle following lidocaine-induced degeneration. A histochemical study.

The histoenzymatic characteristics of regenerating myofibers of rat masseter muscle following injection of 1% lidocaine, as well as morphometric and histochemical characteristics of the typical myofibers, were investigated. Myoblasts appeared initially by day 1 among numerous macrophages within the confines of degenerating myofibers. Myotubes predominated by the 3rd day. Complete regeneration of the muscle occurred by at least 45 days. Phosphorylase activity was absent at day 1 and reappeared by the 5th day when the regenerating myofibers showed slight activity. By the 15th day the myofiber types had partly differentiated; red myofibers were smaller and stained less intensely than the white myofibers. Myotubes stained uniformly for succinic dehydrogenase activity from 3 until 5 days. After 5 days this staining increased gradually. Myofiber types began differentiation by 15 days and were fully differentiated by 45 days. ATPase activity was barely evident by 1-3 days. This activity appeared uniformly low up to 5 days and increased to an intensity comparable with that of the typical myofiber by 15 days. Slight leucine aminopeptidase activity occurred in macrophages 1 day following injection. By 3 days this activity appeared in the remaining myoblasts and in the myotubes. Some activity was found in the fibroblasts. This staining intensity at 5 days was equal to that of earlier lesions. A trace of this activity was found at 7 days, and none at 15 days. Glucose-6-phosphate dehydrogenase activity was present in the macrophages by day 1. It increased by 3 days and occurred mainly in myoblasts and myotubes. This activity decreased by 5 days, and none was found by 7 days.