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Ayrapetyan G.,Chair Life science International Postgraduate Educational Center | Hayrapetyan H.,Chair Life science International Postgraduate Educational Center | Ayrapetyan S.,Chair Life science International Postgraduate Educational Center
Current Chemical Biology | Year: 2016

The effects of non-thermal intensity of microwave (NT MW)- treated physiological solutions (PS) on muscle contractility, 45Ca uptake by muscle and muscle hydration of snail isolated heart in normal and K+-free PS were studied. The intra-cordial perfusion by NT MW-treated PS led to inhibition of heart beating with gradual decrease of the amplitudes of muscle contraction, the weakness of the Na+/K+ pump-induced transient inhibition of heart beating (TIHB), the inhibition of 45Ca2+ uptake by muscle, the increase of intracellular cGMP contents and muscle dehydration. The obtained data serve as additional evidence for hypothesis that cell bathing aqua solution is a primary target for non-thermal effect of MW on cells and organisms. © 2016 Bentham Science Publishers.


Narinyan L.Y.,Chair Life science International Postgraduate Educational Center | Ayrapetyan G.S.,Chair Life science International Postgraduate Educational Center | Ayrapetyan S.N.,Chair Life science International Postgraduate Educational Center
Bioelectromagnetics | Year: 2013

In our previous work we have shown that the age-dependent decrease in the magnetosensitivity of heart muscle hydration is accompanied by a dysfunction of the Na+/K+ pump. The reciprocal relation between the Na+/K+ pump and Na+/Ca2+ exchange in development was suggested as a possible pathway for the age-dependent decrease in the magnetosensitivity of heart muscle hydration (water content). Because high and low affinity ouabain receptors in cell membranes are involved in Na+/Ca2+ exchange and Na+/K+ pump functions, respectively, the effect of a 0.2T static magnetic field (SMF) on dose-dependent, ouabain-induced hydration and [3H]-ouabain binding with heart muscle tissues in young, adult and older rats was studied. Three populations of receptors in membranes with high (10-11-10-9M), middle (10-9-10-7M) and low (10-7-10-4M) affinity to [3H]-ouabain were distinguished, which had specific dose-dependent [3H]-ouabain binding kinetics and effects on muscle hydration. The magnetosensitivity of [3H]-ouabain binding kinetics with high affinity receptors was prominent in all the three age groups of animals, while with low affinity receptors it was more expressed only in the young group of animals. All three types of receptors that caused modulations of muscle hydration were age dependent and magnetosensitive. Based on the obtained data we came to the conclusion that heart muscle hydration in young animals is more magnetosensitive due to the intense expression of high affinity ouabain receptors, which declines with aging. Bioelectromagnetics 34:312-322, 2013. © 2012 Wiley Periodicals, Inc.


Deghoyan A.,Chair Life science International Postgraduate Educational Center | Nikoghosyan A.,Chair Life science International Postgraduate Educational Center | Heqimyan A.,Chair Life science International Postgraduate Educational Center | Ayrapetyan S.,Chair Life science International Postgraduate Educational Center
Electromagnetic Biology and Medicine | Year: 2014

Age-dependent effect of Static Magnetic Field (SMF) on rats in a condition of active and inactive Na+/K+ pump was studied for comparison of brain tissues hydration state changes and magnetic sensitivity. Influence of 15 min 0, 2 Tesla (T) SMF on brain tissue hydration of three aged groups of male albino rats was studied. Tyrode's physiological solution and 10-4 M ouabain was used for intraperitoneal injections. For animal immobilization, the liquid nitrogen was used and the definition of tissue water content was performed by tissue drying method. Initial water content in brain tissues of young animals is significantly higher than in those of adult and aged ones. SMF exposure leads to decrease of water content in brain tissues of young animals and increase in brain tissues of adult and aged ones. In case of ouabain-poisoned animals, SMF gives reversal effects on brain tissue's hydration both in young and aged animals, while no significant effect on adults is observed. It is suggested that initial state of tissue hydration could play a crucial role in animal age-dependent magnetic sensitivity and the main reason for this could be age-dependent dysfunction of Na+/K+ pump. © 2014 Informa Healthcare USA, Inc. All rights reserved.


Narinyan L.,Chair Life science International Postgraduate Educational Center | Ayrapetyan G.,Chair Life science International Postgraduate Educational Center | Ayrapetyan S.,Chair Life science International Postgraduate Educational Center
Bioelectromagnetics | Year: 2012

The reason for hyper magnetosensitivity of young animals compared to older ones remains unclear. It has been suggested that age-induced tissue dehydration (decreased water content) could be a basis for the aging-related decrease in the organism's magnetosensitivity. To test this hypothesis, the effect of a 0.2T static magnetic field (SMF) exposure on heart muscle hydration in three age groups of rats (young, adult, and older) was studied, with and without ouabain poisoning. The SMF exposure resulted in heart muscle dehydration of young (21%) and adult (6.2%) rats but had no effect on older animals. In young animals without ouabin poisoning, SMF exposure caused dehydration of the heart muscle while in the ouabain-poisoned animals it led to hydration (29.6%). These hydration effects were more pronounced in young animals than in adult and older animals. The increased hydration (5.7%) of heart muscles in older animals was evoked by providing distilled water for seven days, which elevated (by 12%) the SMF-induced heart muscle hydration effect. These results suggest that the hyper magnetosensitivity of the young heart muscle and the lower sensitivity of older animals are due to initial high (83.5%) and low (75.3%) tissue hydration levels, respectively. Therefore, the age-induced decrease in the magnetosensitivity of heart muscle is likely to be a result of Na +/K + pump dysfunction. © 2012 Wiley Periodicals, Inc.


Narinyan L.,Chair Life science International Postgraduate Educational Center | Ayrapetyan S.,Chair Life science International Postgraduate Educational Center
Electromagnetic Biology and Medicine | Year: 2016

Previously, we have suggested that cell hydration is a universal and extra-sensitive sensor for the structural changes of cell aqua medium caused by the impact of weak chemical and physical factors. The aim of present work is to elucidate the nature of the metabolic messenger through which physiological solution (PS) treated by non-thermal (NT) microwaves (MW) could modulate heart muscle hydration of rats. For this purpose, the effects of NT MW–treated PS on heart muscle hydration, [3H]-ouabain binding with cell membrane, 45Ca2+ uptake and intracellular cyclic nucleotides contents in vivo and in vitro experiments were studied. It is shown that intraperitoneal injections of both Sham-treated PS and NT MW–treated PS elevate heart muscle hydration. However, the effect of NT MW–treated PS on muscle hydration is more pronounced than the effect of Sham-treated PS. In vitro experiments NT MW–treated PS has dehydration effect on muscle, which is not changed by decreasing Na+ gradients on membrane. Intraperitoneal injection of Sham- and NT MW–treated PS containing 45Ca2+ have similar dehydration effect on muscle, while NT MW–treated PS has activation effect on Na+/Ca2+ exchange in reverse mode. The intraperitoneal injection of NT MW–treated PS depresses [3H]-ouabain binding with its high-affinity membrane receptors, elevates intracellular cAMP and decreases cGMP contents. Based on the obtained data, it is suggested that cAMP-dependent signaling system serves as a primary metabolic target for NT MW effect on heart muscle hydration. © 2016 Taylor & Francis


Dvoretsky A.I.,Oles Honchar Dnepropetrovsk National University | Shainskaya A.M.,Weizmann Institute in Rehovot | Ayrapetyan S.N.,Chair Life science International Postgraduate Educational Center
Environmentalist | Year: 2012

Although the high sensitivity of the Na/K pump in cell membrane to ionizing radiation is well known in literature, the individual role of different isoforms of pump in determination of its radio-sensitivity is not clear yet. This is the subject of the present investigation. Using isotope, electro-physiological and enzymological methods, the effect of γ-ionizing radiation on cell membrane voltage-current characteristics, acetylcholine-induced membrane current, 22Na + and 45Ca 2+ exchange between cells and bathing solution, Na+K +-ATPase activity, dose-dependent ouabain binding with cell membrane, intracellular cAMP and membrane phosphorylation in snail neurons were studied. The changes in neurons as a result of 30-min γ-radiation exposure of snails to 5.16 Ci/kg at the end of the first 30 min of post-radiation period were as follows: the increase in membrane ionic conductance reversed the ouabain sensitivity of acetylcholine-induced currents, stimulation of 22Na + and 45Ca 2+ uptakes, inhibition of Na/K pump, activation Na/Ca exchange in reversed mode, increase in ouabain binding with high-affinity α 3 and decrease with α 2 middle-affinity receptors, decrease in intracellular cAMP content and membrane dephosphorylation. On the basis of the obtained data, it is suggested that both α 3 and α 2 catalytic subunits of Na ++K +-ATPase serve primary membrane sensors through the activation of which the biological effect of γ-radiation on neurons is realized. The IR has activation effects on α 3-dependent Na +/Ca 2+ exchange in forward and its inactivation on α 2-dependent reverse modes. © 2012 Springer Science+Business Media, LLC.


Ayrapetyan S.,Chair Life science International Postgraduate Educational Center
Environmentalist | Year: 2012

At present, when the technological progress brings progressive increase in environmental pollutions by different chemical and physical (ionizing and non-ionizing radiations) factors, the detection of the safety of environmental medium from the point of public health is one of the fundamental problems of modern Life Sciences. This problem has especially disquieting character after the Chernobyl and Japan nuclear catastrophes, when the level of background ionizing radiation and chemical pollutions of environmental medium of the number of world's regions are increased beyond safety doses. As the biological effect of weak environmental factors have nonlinear dose-dependent character, besides its thermodynamic characteristics it depends also on environmental composition and initial state of organism. Therefore, the current policy of World Health Organization and other international organizations whose mission is to establish safety standards for environmental pollutions by chemical and physical factors, based only on the their concentration or energy absorption rate by organism cannot be considered as adequate. It is suggested that the biological marker having universal sensitivity to different factors and determining the functional state of organisms could be used for estimation of the safety doses of environmental factors on organism. In present review are presented the data consisting of the hypothesis according to which the Na/K pump and Na/Ca-controlling cell hydration could serve as a universal and extra-sensitive cellular marker for detection of hazardous effect of environmental pollutions. © 2012 Springer Science+Business Media, LLC.


PubMed | Chair Life science International Postgraduate Educational Center
Type: Journal Article | Journal: Bioelectromagnetics | Year: 2012

The reason for hyper magnetosensitivity of young animals compared to older ones remains unclear. It has been suggested that age-induced tissue dehydration (decreased water content) could be a basis for the aging-related decrease in the organisms magnetosensitivity. To test this hypothesis, the effect of a 0.2 T static magnetic field (SMF) exposure on heart muscle hydration in three age groups of rats (young, adult, and older) was studied, with and without ouabain poisoning. The SMF exposure resulted in heart muscle dehydration of young (21%) and adult (6.2%) rats but had no effect on older animals. In young animals without ouabin poisoning, SMF exposure caused dehydration of the heart muscle while in the ouabain-poisoned animals it led to hydration (29.6%). These hydration effects were more pronounced in young animals than in adult and older animals. The increased hydration (5.7%) of heart muscles in older animals was evoked by providing distilled water for seven days, which elevated (by 12%) the SMF-induced heart muscle hydration effect. These results suggest that the hyper magnetosensitivity of the young heart muscle and the lower sensitivity of older animals are due to initial high (83.5%) and low (75.3%) tissue hydration levels, respectively. Therefore, the age-induced decrease in the magnetosensitivity of heart muscle is likely to be a result of Na(+)/K(+) pump dysfunction.


PubMed | Chair Life science International Postgraduate Educational Center
Type: Journal Article | Journal: Electromagnetic biology and medicine | Year: 2012

Non thermal (NT) effect of direct radiation 4Hz-modulated 90-160GHz of Millimeter Waves (MMW) and preliminary MMW-treated physiological solution (PS) influence were studied on snail isolated neuron, rats brain tissue hydration and skin penetration. It was shown that the 4Hz-modulated low intensity 90-160GHz MMW direct radiation and MMW-treated PS leads to on single neuron shrinkage, skin and brain tissue dehydration. On the basis of obtained data it was suggested that the cell bathing aqua medium serve as a target through which the NT effect of MMW on cell hydration is realized. The MMW-induced brain tissue dehydration can considering as consequence of MMW-induced skin water structural changes leading to unknown messenger formation able to modulate the brain cell hydration. The extrasensitivity of cell hydration to low intensity of MMW radiation allow to recommend cell hydration as a cellular marker for estimation of the NT biological effect of MMW on cells and organisms.


PubMed | Chair Life science International Postgraduate Educational Center
Type: Journal Article | Journal: Electromagnetic biology and medicine | Year: 2013

The aim of the present work was to investigate the frequency-dependent effects of mechanical vibration at infrasound frequency (MV at IS frequency or MV) on E. coli K-12 growth by investigating the cell proliferation, using radioactive [(3)H]-thymidine assay. The frequency-dependent effects of MV were shown that it could either stimulate or inhibit the growth of microbes. However, the mechanism through which the MV effects affect the bacterial cells is not clear yet. It was suggested that the aqua medium can serve as a target through which the biological effect of MV on microbes could be realized. To check this hypothesis the frequency-dependent effect (2, 4, 6, 8, 10Hz) of MV on the bacterial growth in cases of exposure the preliminary treated microbes-free medium and microbes containing medium were studied. It has been shown that MV at 4, 8, and 10Hz frequency has inhibition effects, while at 2 and 6Hz has stimulation effects on cell proliferation.

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