Effects of static magnetic field pretreatment with and without PEG 6000 or NaCl exposure on wheat biochemical parameters

In this study, the static magnetic field (SMF) flux of 2.9–4.7 mT was applied to mature embryo explants of Tekirdag and Selimiye wheat cultivars (Triticum aestivum L.) under tissue culture conditions at three different pretreatment times of 0, 2.2, and 19.8 s, at the rate of 1 m/s with and without 60 g/L PEG 6000 or 100 mM NaCl. Changes in different biochemical parameters were investigated. SMF pretreatment with and without 60 g/L PEG 6000 or 100 mM NaCl increased chlorophyll and carotenoid contents, FRAP values, and antioxidant enzyme (SOD, CAT, POX, and APX) activities in all experimental groups except for the activities of Mn-SOD in the cv. Selimiye root samples. Among SOD isozymes, Fe-SOD was affected by SMF stronger than other izozymes. The combinations of SMF pretreatment with and without 60 g/L PEG 6000 or 100 mM NaCl differently affected SOD isozyme activities besides its effects on other biochemical parameters.     

Effects of high static magnetic field exposure on different DNAs

The effects of magnetic fields produced by permanent magnets on different DNA sources were investigated in vivo and in vitro. Escherichia coli DNA, plasmid, and amplification products of different lengths were used as the magnetic field target. The in vivo assays did not reveal any DNA alterations following exposure, demonstrating the presence of cell dependent mechanisms, such as the repair system and the buffering action of the heat shock proteins DNA K/J (Hsp 70/40). The in vitro assays displayed interactions between the magnetic field and DNA, revealing principally that magnetic field exposure induces DNA alterations in terms of point mutations. We speculate that the magnetic field can perturb DNA stability interacting with DNA directly or potentiating the activity of oxidant radicals. This genotoxic effect of the magnetic field, however, is minimized in living organisms due to the presence of protective cellular responses.     

Effects of short-term exposure to pulsed electromagnetic field on some biochemical parameters in mice

Five-months-old male albino mice were subjected to an electromagnetic field (EMF) of 5 mT of magnitude with a frequency of 60 Hz for 8hr of single application. Analysis of blood sampled on hourly basis (up to 8 hr) for levels/activities of total protein, albumin, globulin, uric acid, creatinine, cholesterol, and alkaline phosphatase indicated no significant differences (p > 0.05) from that of the control group.     

Acute exposure to a moderate strength static magnetic field reduces edema formation in rats

External application of static magnetic fields (SMF), used specifically for the treatment of inflammatory conditions such as soft tissue injuries, has recently become popular as a complementary and/or alternative therapy with minimal investigation into efficacy or mechanism. Localized inflammation was induced via injection of inflammatory agents lambda-carrageenan (CA) or histamine into rat hindpaws, alone or in conjunction with pharmacological agents, resulting in a spatially and temporally defined inflammatory reaction. Application of a 10- or 70-mT, but not a 400-mT, SMF for 15 or 30 min immediately following histamine-induced edema resulted in a significant, 20-50% reduction in edema formation. In addition, a 2-h, 70-mT field application to CA-induced edema also resulted in significant (33-37%) edema reduction. Field application before injection or at the time of maximal edema did not influence edema formation or resolution, respectively. Together, these results suggest the existence of a therapeutic threshold of SMF strength (below 400 mT) and a temporal dependence of efficacy. Administration of pharmacological agents directed at nitric oxide signaling and L-type Ca(2+) channel dynamics in conjunction with SMF treatment and histamine-induced edema revealed that the potential mechanism of SMF action may be via modulation of vascular tone through effects on L-type Ca(2+) channels in vascular smooth muscle cells.     

Devices for gradient static magnetic field exposure

We describe devices designed for magnetic field exposures in which field amplitude and gradients are controlled simultaneously. Dosimetry based on field continuation of high resolution magnetic field scans and numerical models is compared with validation measurements. The dosimetry variables we consider are based on the assumption that the biological or chemical system under study has field transducers that are spatially isotropic, so that absolute field amplitude and two gradient components fully describe local exposure.     

The effects of long-term exposure of magnetic field via 900-MHz GSM radiation on some biochemical parameters and brain histology in rats

The aim of this study is to determine the effects of magnetic field via cell phones on some blood parameters and neurons in the brain of rats. Animals have been classified into three groups: control, Magnetic Field (MF), and F2 groups. Throughout this study, cell phones were placed on the wall of the cages. Rats were exposed to the effects of cell phones during prenatal and postnatal periods until they were 80 days old. During the study, the exposure procedure of rats was that the phone was in standby mode for a whole day and in talking mode for 30 min per day. The waves of cell phones caused an increased blood glucose level from 96.52 ± 5.64 mg/dl to 132.14 ± 5.93 mg/dl and an increased serum protein level from 131.14 ± 6.19 mg/dl to 319.29 ± 6.73 mg/dl compared to control. Statistically, significant differences wasn't observed in the blood cholesterol concentration between the groups compared to the control. Weekly weight gain decreased in all groups compared to the control. MF exposure decreased pyramidal neuron numbers 51.15% and increased ischemic neuron numbers 73% at cortex region of brain. In addition, vascular dilatations have increased clearly in group F2.Whereas the procedure of MF did not have any effects on hippocampal pyramidal cell numbers, magnetic fields increased the amount of ischemic neurons three-fold compared to the control. In conclusion, MF affected some biochemical parameters, especially the cortex region of the brain.     

Effects of 12 mT static magnetic field on sympathetic agonist-induced hypertension in Wistar rats

We investigated the combined effects of a moderate-intensity static magnetic field (SMF) and two different sympathetic agonists, an alpha(1)-adrenoceptor agonist, phenylephrine and a beta(1)-adrenoceptor agonist, dobutamine, which induced hypertension and different hemodynamics in Wistar rats. Five-week-old male rats were continuously exposed to the SMF intensity of 12 mT (B(max)) with the peak spatial gradient of 3 mT/mm for 10 weeks. A loop-shaped flexible rubber magnet was adjusted to fit snugly around the neck region of a rat (diameter-adjustable to an animal size). Sham exposure was performed using a dummy magnet. Six experimental groups of six animals each were examined: (1) sham exposure with intraperitoneal (ip) saline injection (control); (2) SMF exposure with ip saline injection (SMF); (3) sham exposure with ip phenylephrine (1.0 microg/g) injection (PE); (4) SMF exposure with ip phenylephrine injection (SMF + PE); (5) sham exposure with ip dobutamine (4.0 microg/g) injection (DOB); (6) SMF exposure with ip dobutamine injection (SMF + DOB). Fifteen minutes after the injection of each agent, the first set of parameters, arterial blood pressure (BP) and heart rate (HR), the second set of parameters, skin blood flow (SBF) and skin blood velocity (SBV), or the third set of parameters, the number of rearing (exploratory behavior) responses and body weight was monitored. Each agent was administered three times a week for 10 weeks, and each set of parameters was monitored on different days, once a week. The dose of phenylephrine significantly increased BP and decreased HR, SBF, SBV, and the number of rearing responses in the PE group compared with those in the respective age-matched control group. The dose of dobutamine significantly increased BP and HR, increased SBF, SBV, and the number of rearing responses in the DOB group compared with those in the control group. Continuous neck exposure to the SMF alone for up to 10 weeks induced no significant changes in any of the measured cardiovascular and behavioral parameters. The SMF exposure for at least 2 weeks (1) significantly depressed phenylephrine effects on BP, SBF, SBV, and rearing activity (SMF + PE group vs. PE group); (2) significantly depressed dobutamine effects on BP, SBF, and SBV, and suppressed dobutamine-induced increase in the rearing activity (SMF + DOB group vs. DOB group). These results suggest that continuous neck exposure to 12 mT SMF for at least 2 weeks may depress or suppress sympathetic agonists-induced hypertension, hemodynamics, and behavioral changes by modulating sympathetic nerve activity.     

Effects of neck exposure to 5.5 mT static magnetic field on pharmacologically modulated blood pressure in conscious rabbits

Static magnetic fields (SMF) in the millitesla (mT) range have been reported to modulate microcirculatory hemodynamics and/or blood pressure (BP) under pharmacologically modified state in mammals. This study was designed to investigate the acute effects of local application of a SMF to neck or pelvic region under pharmacologically modulated BP; norepinephrine (NE)-induced hypertension as well as an L-type voltage-gated Ca(2+) channel blocker, nicardipine (NIC)-induced hypotension in conscious rabbits. Magnetic flux densities were up to 5.5 mT and the spatial magnetic gradient peaked in neck (carotid sinus baroreceptor) region at the level of approximately 0.06 mT/mm. The duration of exposure was 30 min (including 10 min of pretreatment) and the effects on BP were investigated up to 100 min postexposure. Baroreflex sensitivity (BRS) was estimated from invasive recordings of systolic BP and pulse interval. Neck exposure to 5.5 mT significantly attenuated the pharmacologically induced vasoconstriction or vasodilation, and subsequently suppressed the increase or decrease in BP compared with sham exposure. In contrast, pelvic exposure to 5.5 mT did not significantly antagonized NE-elevated BP or NIC-reduced BP. The neck exposure to 5.5 mT has a biphasic and restorative effect on vascular tone and BP acting to normalize the tone and BP. The neck exposure to 5.5 mT caused a significant increase in BRS in NE-elevated BP compared with sham exposure. The buffering effects of the SMF on increased hemodynamic variability under NE-induced high vascular tone and NIC-induced low vascular tone might be, in part, dependent on baroreflex pathways, which could modulate NE-mediated response in conjunction with Ca(2+) dynamics.     

Time-dependent effects of exposure to static magnetic field on glucose and lipid metabolism in rat

In the following study, we investigate the effects of static magnetic field (SMF) (128 mT, 1 h/day during 5 or 15 consecutive days) on anthropometric parameters, glucose and lipid metabolism in rats. Exposure to SMF during 5 days induced a decrease (-8%, p < 0.05) in relative liver weight and serum insulin concentration (-56%, p < 0.001), while blood glucose level was increased (+10%, p < 0.001). By contrast, the same treatment failed to alter body weight, relative kidney weight and levels of lactate, cholesterol, triglycerides and phospholipids. Exposure to SMF during 15 days induced a decrease (-15 %, p < 0.001) in body weight, liver weight (-15 %, p < 0.05), insulin concentration (-63%, p < 0.001), plasmatic lactate level (-55%, p < 0.05) and increased glucose (+24%, p < 0.001), cholesterol (+30%, p < 0.01,) and phospholipids levels (+58%, p < 0.001), whereas, triglycerides decreased (-28%, p < 0.001). These results showed that SMF effects on glucose and lipid metabolism are time-dependent.     

Effects of 25 mT static magnetic field on blood pressure in reserpine-induced hypotensive Wistar-Kyoto rats

We investigated the interrelated antihypotensive effects of static magnetic fields (SMF) and plasma catecholamine levels in reserpine-induced hypotensive Wistar-Kyoto rats. Seven-week-old male rats were exposed to two different ranges of SMF intensities, 3.0-10 mT (Bmax) or 7.5-25 mT (Bmax) for 12 weeks. Six experimental groups of 10 animals each were examined: (1) no exposure with intraperitoneal (ip) saline injection (sham exposed control); (2) 10 mT SMF exposure with ip saline injection (10 mT); (3) 25 mT SMF exposure with ip saline injection (25 mT); (4) no exposure with ip reserpine injection (RES); (5) 10 mT SMF exposure with ip reserpine injection (10 mT + RES); (6) 25 mT SMF exposure with ip reserpine injection (25 mT + RES). Reserpine (5 mg/kg) was administered three times a week for 12 weeks, and 18 h after each injection, arterial blood pressure (BP), heart rate, skin blood flow, plasma nitric oxide metabolites, plasma catecholamine levels, and behavioral parameters of a functional observational battery (FOB) were monitored. The action of reserpine significantly decreased BP, reduced plasma norepinephrine (NE), increased the FOB hunched posture score and decreased the number of rearing events in the RES group, compared with the respective age-matched control group. Exposure to 25 mT, but not 10 mT, for 2-12 weeks significantly prevented the reserpine-induced decrease of BP in the 25 mT + RES group compared with the respective RES group. Moreover, exposure to 25 mT for 5 weeks partially suppressed the reserpine-induced NE reduction, but did not bring about a complete reversal of reserpine effects. NE levels for the 25 mT + RES group for 5 weeks were significantly higher compared with the RES group, but still lower compared with the control group. In addition, the FOB hunched posture score for the 25 mT + RES group was significantly lower and the number of rearing events was higher compared with the RES group, but these behavioral parameters did not revert to control levels. There were no significant differences in any of the physiological or behavioral parameters measured between the 10 mT + RES and RES groups, nor between the two different SMF groups and the control group. These results indicate that 25 mT SMF with spatial gradients significantly suppressed the reserpine-induced hypotension and bradykinesia. The antihypotensive effects of SMF on the reserpine-treated group might be at least partially related to the inhibition of NE depletion.     

Effect of static magnetic field on some enzymes activities in rats

The magnetic field of 0.008 T and 0.15 T inductions influence lasting 7 weeks (7 days a week), 1 h daily determines the increase of the activity of cytoplasmatic enzymes (glutamic pyruvic transaminase, glutamic oxalacetic transaminase, lactic dehydrogenase), the decrease of cholinesterase activity and the growth of alkaline phosphatase activity in the plasma of the examined animals. The observed changes were reversible. 2 months after the exposure had been stopped, the tested parameters were back to normal.     

Morphological and biochemical modifications induced by a static magnetic field on Fusarium culmorum

The effects of the exposure to a static magnetic field (sMF) of 0.3 +/- 0.03 T on the Fusarium culmorum were investigated in vitro. sMF inhibition of mycelia growth was accompanied by morphological and biochemical changes. Fungal conidia germination and cell viability were also reduced. We provide evidence of the influence of sMF on Ca(2+)-dependent signal transduction pathways involved in conidia germination. Perturbation of these pathways by adding different compounds (i.e. CaCl(2), phorbol 12-myristate 13-acetate, neomycin, EGTA, LiCl) to the medium, suggested that exposed conidia are unable to mobilise calcium from intracellular stores and that the hindered mechanism may be IP(3)-dependent.     

Development of mouse testis and epididymis following intrauterine exposure to a static magnetic field

In order to test if the in utero exposure to static magnetic fields affects testis and epididymis development in mice, females were exposed to 0.5-0.7 T, generated by a permanent magnet, from day 7 of gestation to the day of birth. No significant differences were found between exposed and sham-exposed animals with respect to body weight gain of dam during the gestational period, litter size, body weight of male pups at the day of birth, and body or testis-epididymis weight gain of pups from birth to day 35. Histopathologic evaluation of testis and epididymis of pups of 1, 5, 15, and 35 days of age showed no detectable alterations due to in utero exposure to static magnetic fields.     

Optimization of static magnetic field parameters improves analgesic effect in mice

The present study deals with the analgesic effect induced by static magnetic fields (SMF) in mice exposed to the field with their whole body. It discusses how the effect depends on the distribution of the magnetic field, that is, on the specification and arrangement of the applied individual permanent magnets. A critical analysis of different magnet arrangements is given. As a result the authors propose a magnet arrangement recipe that achieves an analgesic effect of over 80% in the writhing test. This is a widely accepted screening method for animal pain and predictor of human experimental results. As a non-drug, non-invasive, non-contact, non-pain, non-addictive method for analgesia with immediate and long-lasting effect based on the stimulus of the endogenous opioid network, the SMF treatment may attract the attention of medical doctors, nurses, magnet therapists, veterinarians, physiotherapists, masseurs, and fitness trainers among others.     

The effects of low-frequency magnetic field exposure on the growth and biochemical parameters in lupin (Lupinus angustifolius L.)

The influence of frequent magnetic field stimulation (MFS) on plants is the subject of intense research. The effects of MFS on plants vary depending on its intensity, time of exposure or application form. The effects of low-frequency magnetic field in two doses, 0.2 mT, 16 Hz (MFS-1) and 0.2 mT, 50 Hz (MFS-2) on the mitotic activity and selected physiological and biochemical parameters in narrow-leafed lupin (Lupinus angustifolius L.) were evaluated. Non-exposed plants were used as control (C). It was noted that after the exposure of plants to MFS-1, the biometric parameters, mitotic activity, BSA and GPOX activity remained at the control level. However, a significant decrease in the assimilation pigment content was observed. On the other hand, the exposure of plants to MFS-2 was manifested by a decrease in the biometric parameters, mitotic activity and the assimilation pigment content, but an increase in GPOX activity in roots was noted.     

Skin temperature changes induced by strong static magnetic field exposure

High intensity static magnetic fields, when applied to the whole body of the anesthetized rat, have previously been reported to decrease skin temperature. The hypothesis of the present study was that in diamagnetic water, molecules in the air play significant roles in the mechanism of skin temperature decrease. We used a horizontal cylindrical superconducting magnet. The magnet produced 8 T at its center. A thermistor probe was inserted in a subcutaneous pocket of the anesthetized rats to measure skin temperature. Animals (n=10) were placed in an open plastic holder in which the ambient air was free to move in any direction (group I). Animals (n=10) were placed in a closed holder in which the air circulation toward the direction of weak magnetic field was restricted (group II). Each holder was connected to a hydrometer to measure humidity around the animal in the holder. The data acquisition phase consisted of a 5 min baseline interval, followed by inserting the animal together with the holder into the center of the magnet bore for a 5 min exposure and a 5 min postexposure period outside the bore. In group I, skin temperature and humidity around the animal significantly decreased during exposure, followed by recovery after exposure. In group II, skin temperature and humidity did not decrease during the measurement. The skin temperature decrease was closely related to the decrease in humidity around the body of the animal in the holder, and the changes were completely blocked by restricting the air circulation in the direction of the bore entrance. Possible mechanisms responsible for the decrease in skin temperature may be associated with magnetically induced movement of water vapor at the skin surface, leading to skin temperature decrease.     

Effects of exposure to a circularly polarized 50-Hz magnetic field on plasma and pineal melatonin levels in rats

We sought to determine whether a 6-week exposure to a 50-Hz rotating magnetic field influences melatonin synthesis by 11–18 week-old Wistar-King male rats. Rats were exposed continuously to a rotating magnetic field at 1, 5, 50, or 250 μT (spatial vector rms) for 6 weeks, except for twice-weekly breaks of about 2 h for cleaning of cages and feeding. The rats were housed in exposure and sham-exposure facilities, which were located in the same room, under a 12:12 light-dark photoperiod (lights on at 06:00 h). The room was constantly illuminated by 4 small, dim red lights (< 0.07 lux in dark period). Levels of plasma and pineal gland melatonin were determined by radioimmunoassay. A significant decrease of melatonin was observed between the control group and groups exposed to a magnetic field at a flux density in excess of l μT during the night time, but no statistical differences were found among the exposed groups. These results indicate that subchronic exposure of albino rats to a 50-Hz rotating magnetic field influences melatonin production and secretion by the pineal gland. © 1993 Wiley-Liss, Inc.     

Differentiation of monocytic U937 cells under static magnetic field exposure

We present here a morphological, cytochemical and biochemical study of the macrophagic differentiation of human pro-monocytic U937 cells exposed to moderate intensity (6 mT) static magnetic fields (MF). It was found that the following substances induced differentiation in U937 cells to a progressively lower degree: 50 ng/mL 12-0-tetradecanoyl-13-phorbol acetate (TPA), low concentration of glutamine (0,05 mM/L), 10% dimethyl sulfoxide (DMSO) and 100 mM/L Zn++. Differentiated U937 cells shift from a round shape to a macrophage-like morphology, from suspension to adhesion growth and acquire phagocytotic activity, the cytoskeleton adapting accordingly. Exposure to static MF at 6 mT of intensity decreases the degree of differentiation for all differentiating molecules with a consequent fall in cell adhesion and increased polarization of pseudopodia and cytoplasmic protrusions. Differentiation alone, or in combination with exposure to static MFs, affects the distribution and quantity of cell surface sugar residues, the surface expression of markers of macrophage differentiation, and phagocytotic capability. Our results indicate that moderate-intensity static MFs exert a considerable effect on the process of macrophage differentiation of pro-monocytic U937 cells and suggest the need for further studies to investigate the in vivo possible harmful consequences of this.