Cell Bathing Medium as a Target for Non-thermal Effect of MMW (EHF) on Heart Muscle Contractility
G. S. Ayrapetyan, E. H. Dadasyan, E. R. Mikayelyan,
S. V. Barseghyan, and Sinerik Ayrapetyan
UNESCO Chair-Life Sciences International Postgraduate Educational Center, Armenia
Abstract— The comparative study of the effects of weak intensity specific absorption rate (SAR = 1.8 mW/g) of 4Hz modulated 160 GHz millimeter wave (MMW) and near Infrared (IR) irradiation on thermodynamic properties, specific electrical conductivity (SEC) of physiological solution (PS) and hydrogen peroxide (H2O2) formation in it as well as the effect of MMW- treated PS on heart muscle contractility, 45Ca uptake was performed. The heat fusion capacity of MMW-pretreated PS after freezing by liquid nitrogen (N2) is significantly less than the heat fusion capacity of sham and IR-treated PS. MMW unlike IR, has time-dependent elevation effect on water SEC and SAR, which is accompanied by the increase of H2O2 formation in it. The direct MMW radiation, MMW-pretreated PS and H2O2-containing PS have increasing effect on heart muscle contractility. The MMW-pretreated PS and the H2 O2 –containing PS have activation effect on 45Ca uptake and dehydration effect on heart muscle contractility. Thus, the obtained data allow us to consider water dissociation as a main target through which the non-thermal effect of MMW on physicochemical properties of water is realized, while the MMW-induced formation of H2O2 in cell bathing medium serves as a messenger through which the modulation of intracellular metabolism takes place.
1. INTRODUCTION
The phenomenon of non-thermal biological effect of low intensity Millimeter Waves (MMW) has been known for several decades (Devyatkov 1973; Adey 1981; Lin 2004; Belyaev 2005). Although, it is more and more widely used in alternative treatments of a variety of diseases (Ziskin 2006; Markov 2007), the physicochemical mechanisms underlying the non-thermal biological effect of MMW still remain unclear.
As MMW penetration in body depths is only a few tenths of a millimeter, it is suggested that the therapeutic effect on organisms is initiated by water within the skin components (∼ 70%), for which the absorption coefficient is the largest (Ziskin, 2006). However, the nature of low intensity MMW-induced changes of physicochemical properties of extracellular water, which could modulate cell metabolic activity, is not clear yet.
Although the higher sensitivity of hydrogen bonding makes water dissociation as one of the most variable properties of water, adequate attention has not been paid by investigators to water ioniza- tion as a universal and extra sensitive “primary” target for the biological effects of weak intensity environmental factors, including electromagnetic fields (EMF) (Szent-Gyorgyi 1968; Klassen 1982). It is known that even partial alignment of water molecules with the electric field may bend or break the hydrogen bonding (Chaplin 2008). Therefore, it is predicted that the MMW-induced wa- ter dipole vibration could increase water dissociation and in presence of oxygen (O2) form reactive oxygen species (ROS), which are strong modulators for cell metabolism. The formation of hydro- gen peroxide (H2O2) upon the high intensity MMW has been demonstrated (Gudkova et al. 2005). However, the possibility of ROS generation in water and water solutions upon the influence of extremely low intensity MMW is not clear yet.
For checking the above mentioned hypothesis whether the weak intensity MMW could modulate the water dissociation and generate H2O2, through which the effect of MMW on heart contractility is realized, the following two series of experiments were performed in present work:
1. A comparative study of the effects of MMW and near IR (1–100 THz) radiation on physico- chemical properties of PS.
2. A comparative study of the effects of MMW-pretreated and H2O2-containing PS on heart muscle contractility, 45Ca-uptake.
2. METHODS
As an experimental model serves PS (composition (in mM) NaCl-80, KCl-4, CaCl2-7, Tris-HCl-5, pH-7.5) and isolated-intracordial perfused heart muscle of snail Helix pomatia. The MMW generator
“Artsakh-04M” (Russian production), designated for clinical applications, which generates 90– 160 GHz MMW modulated by 4 Hz EMF was used. As IR source serves the “NOVAFLEX” Fibber Optic Illuminator (World Precision Instruments, USA) with near IR light filter. The determination of SAR (SAR = Cw(PS)∆T/∆t) of PS and heart for MW and IR radiation was used a high-precision differential calorimetric device “Biophys MWD-001” (Simonyan et al. 2006). For the determination of H2O2 content, the enhanced chemiluminescence method in a peroxidase-luminol-p-iodophenol system was used. The chemiluminescence and 45Ca uptake by muscle were quantified by “Walac” liquid scintillation counter (Finland production).
2.1. The Comparative Study of MMW and IR Radiation on Physicochemical Properties of PS
As the SEC of water solutions is determined by ions, in order to find out whether MMW radiation leads to water ionization, the comparative study of the effects of MMW and IR radiation on SEC of PS was performed.
The data presented on Figure 1 show that at 18◦C the SEC of 10-min-MMW-pretreated PS is significantly higher (4.1%) than in case of equivalent intensity IR-preheated and sham-treated PS. It is worth to note that the second 10min of MMW exposure (a′) has more pronounced elevation effect (50.2 %) on PS SEC than the first 10 min of exposure (a), while in case of IR irradiation both, the first (b) and the second (b′) 10 min of exposures have the same effect on PS SEC (Figure 1(a)).
It is known that the SAR of water is related to electrical conductivity (σ) and density (ρ) expressed as SAR = σE2/ρ, where E is electric field intensity. Therefore, it is predicted that the MMW-induced possible changes of water dissociation could cause time-dependent changes of water SAR during MMW radiation. To check this hypothesis the thermal effects of double exposure of MMW and IR radiation on PS for 10 min (with 10 min intervals) were studied. During 10 min inter- exposure period the temperature of PS samples was returned to the initial temperature (18◦C).
