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The effects of adrenergic agonists (epinephrine, norepinephrine, isoprenaline, salbutamol, phenylephrine, clonidine) and antagonists (propranolol, sotalol, oxprenolol, methoprolol, atenolol) on the production of reactive oxygen (RO) by macrophages (MFs) were studied in vitro using chemiluminescence techniques. It was established that beta-adrenomimetics suppressed, whereas alpha-adrenomimetics enhanced or did not change the RO, production by MFs. Possible mechanisms and the biological significance of the adrenergic modulation NADPH-dependent RO, generation are discussed.

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Daily introduction per os of the exogenous melanin in a doze of weight of 10 mg/kg pregnant female rats Wistar eliminated the functional deficiency of somatic development revealed at posterity at chronic gamma-irradiation in a doze 1.00-1.25 Gy for all period of pregnancy. The irradiation or introduction melanin antenatal to a phase ontogenesis resulted in stimulation of the immune answer, which was determined at offspring on 3rd week after birth. On the basis of the received data it is concluded presence radioembryoprotective actions melanin in the relation embryotoxic effects of small dozes of ionizing radiation and its participation in regulation immunogenes.

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Daily introduction per os of the exogenous melanin in a doze of weight of 10 mg/kg pregnant female rats of line Wistar on a background continuous irradiations (dose rate of 2.6 mGy/h within 20 days of pregnancy) eliminated deficiency cognitive functions at posterity. On the basis of the received data it is concluded presence radioembryoprotective actions of melanin in the relation neuro embryotoxic effects of small dozes ionizing radiation. Taking into account small toxicity of melanin, the preparation can be perspective for practical application.

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Research has been carried out to investigate the effects of pulsed microwave exposure without pause (7 GHz, 400 pps, 100 microseconds, 70-150 mW/cm2, exposure 10 min) and pulsed interrupted cyclical microwave exposure (5 min exposure--4 min pause--5 min exposure) on learned behaviors of rats in the paradigm of extraordinary situation (the rescue of the life). It was shown that reductions in conditioned behavior after acute pulsed microwave exposure occurred at SAR of 21 W/kg (100 mW/cm2) and after cyclical pulsed microwave exposure at SAR of 28.4 W/kg (135 mW/cm2).

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Research has been carried out to investigate the effects of microwave exposure (7 GHz, surface energy density 10-50 mW/cm2, SAR 2.1-10.5 W/kg) on learned behaviors of rats in the paradigm of conditioned avoidance reflex. It was shown that transitory reductions in conditioned behavior after acute microwave exposure occurred at an SAR equal to the intensity of rat basal metabolism. It was found cumulative effects for intermittent exposures of rats at a power density of 10 mW/cm2.

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Pigment melanin peroral injection was shown to decrease significantly mutagenic action of chronic irradiation at low dose rate (0.007 Gy/h), and melanin protection against chronic irradiation is even more effective than against acute one. A phenomenon of radioadaptive response was revealed in mice in vivo by tests of chromosome aberrations in bone marrow cells and reciprocal translocations in germ cells. Adaptive response before priming dose was not observed if melanin was injected. If melanin was applied between conditioning and basic doses both radioprotective and adaptive effects were observed.

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The influence of microwaves and heat on dynamics of heating of samples of intact and inactivated bacteria Escherichia coli and solutions of some basic molecular components of cell was investigated. It was shown that microwaves induce different dynamics of heating of all samples. On the contrary, thermal action induces identical dynamics of heating of all this samples except vegetable oil which was heated more intensively.

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Based on the devised calorimetric equipment the values of absorbed doses of UHF-radiation were obtained for laboratory animals. The advantage of application of the specific absorption rate (SAR) and the absorbed dose in comparison with exposure dose and energy flux density was demonstrated. The influence of SAR on lethality in laboratory animals was investigated. It was shown that interspecific sensitivity of laboratory animals was dependent on SAR.

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The thermal and specific effects of cm range microwaves on cell systems was investigated. It was shown that cell damage (killing and permeability disturbance) in Escherichia coli B/r, Escherichia coli Bs-1, Saccharomyces cerevisiae and ACE were induced by microwave heating more effectively than by equivalent thermal heat.

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In electrophysiological experiments with a preparation of the isolated Helix pomatia brain, a study was made of the effect of pulsed irradiation with high-energy electrons (20 MeV) on membrane potentials and pulse activity of "silent", pacemaking and postsynaptic neurons. It was shown that after irradiation with 150 and 300 Gy (dose rate 5 Gy/s and pulse frequency 50 Hz) "silent" neurons retain their excitability. Pacemaking neurons responded to radiation by a drastic increase in spontaneous pulse activity followed by its transfer to a clipped then to an irregular one. At the same time, the discharge frequency increased in the postsynaptic neurons.

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Based on the swimming test according to Kiplinger, in experiments on (CBA X C57BL)F1 mice there were elaborated criteria for animal performance evaluation in the process of repeated swimming of a standard distance thus measuring power, volume of work and rate of the fatigue development in relative units. From the study of effects of sydnocarb, bemethyl and phenazepam on various parameters of physical performance of mice a conclusion was made that the proposed method provides a more informative evaluation of the pharmacological effect on physical performance of animals as compared to the methods based on the record of time of performing the load.

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In experiments on mice, a pronounced haemostimulating effect of prostaglandin biosynthesis inhibitors was registered in conditions of fractionated irradiation. The use of the preparations like these may be promising in solving the problem of protection of the haemopoietic tissue exposed during the radiotherapy course.

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No activation of lipid peroxidation and structural rearrangements were noted in the lipid phase of synaptosome membranes after exposure of animals to electrons of 300 Gy/min at doses inducing cerebral lesions. At the same time, in isolated synaptosome membranes, radiation induced defined changes manifested by a decrease in tryptophan fluorescence.

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Activities of alpha-hydroxybutyrate- and lactate dehydrogenases (HBDH, LDH), aspartate- and alanine aminotransferases (AST, ALT), alkaline phosphatase, alpha-amylase as well as content of total proteins, glucose, cholesterol, triglycerides and Ca2+ were estimated sprectrophotometrically in blood serum of rat males within 2 hrs after thermic burns of the III degree involving 15% the body surface. The burns caused about 2-fold increase in activities of LDH, HBDH and AST and in content of triglycerides in blood serum but did not affect the other biochemical patterns. Adrenalectomy, carried out within 3 days before the burns, accelerated and pseudoadrenalectomy decreased the early postburn enzymatic activation. Preadministration of reserpine, phentolamine and obsidane (propranolol) decreased distinctly the hyperenzymic reaction observed after the burn stress.

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The radioactive ligands, [3H]dihydroalprenolol and [3H]muscimol, were used to estimate the condition of beta-adrenoreceptors of the brain cortex and GABA-receptors of the cerebellum during transient neurologic disorders caused by irradiation of rats with high-energy (20 MeV) electrons of 200 Gy. No significant changes were observed in the GABA-ergic brain system while the changes in beta-adrenoreceptors of the brain were pronounced and manifested by the loss by the receptors of their ability to bind the specific ligand, dihydroalprenolol. The changes observed were reversible and correlated with the development of neurologic disorders.

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In experiments on mice it was demonstrated that after the administration of indomethacin the CFUc, survived after the irradiation, enter the exponential phase of growth 3 days earlier than the controls do. The time of doubling of cells in number is invariable. The accelerated repopulation of haemopoietic cells improves the haemopoiesis status at the height of acute radiation sickness.

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The administration to mice of preparations inhibiting prostaglandin synthesis was shown to reduce the post-irradiation cytopenia in the peripheral blood and to increase the total cellularity of the bone marrow and the yield of splenic endocolonies. When the exposed mice were injected with intact myelocaryocytes, at the background of the inhibited prostaglandin biosynthesis, the number of exogenous colonies increased.

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