Thuroczy G, Kubinyi G, Bodo M, Bakos J, Szabo LD, · 1994
At 30 mW/cm², total EEG power increased, while at 10 mW/cm² EEG did not change but cerebral blood flow increased. Brain-localized 4 GHz continuous-wave exposure at 42 mW/g SAR increased EEG delta power and REG amplitude simultaneously.
Liddle CG, Putnam JP, Huey OP · 1994
Female CD1 mice were exposed from the thirty-fifth day of age for the remainder of their lives to 2.45 GHz CW microwave radiation at 3 or 10 mW/cm2. Exposures took place 1 h/day, 5 day/week in an anechoic chamber at an ambient temperature of 22 degrees C and a relative humidity of 50%. There were 25 animals in each exposure group, and an equal number of controls were concurrently sham exposed. The average life span of animals exposed at 10 mW/cm2 was significantly shorter than that of sham-exposed controls (572 days vs. 706 days; P = .049; truncation > 20%). In contrast, the average lifespan of the animals exposed at 3 mW/cm2 was slightly, but not significantly, longer (738 days) than that of controls (706 days).
Philippova TM, Novoselov VI, Alekseev SI · 1994
Researchers studied the effects of continuous wave and pulse-modulated 900 MHz microwave fields on rat chemoreceptors using in vitro assays. Binding of H3-glutamic acid to hippocampal cells was unchanged after 15 minutes of continuous wave exposure at 1 W/kg, while binding of H3-dihydroalprenolol to neonatal liver-cell membranes decreased fivefold under the same conditions. The decrease was due to shedding of receptor elements into solution and correlated with oxygen concentration in the suspension.
Phelan AM, Neubauer CF, Timm R, Neirenberg J, Lange DG · 1994
Researchers exposed Sprague-Dawley rats to microwave radiation at 2.45 GHz and 80 mW/cm² for 30 minutes daily over four days, raising rectal temperature by 2.2°C. A separate group received radiant heat producing the same temperature rise. Microwave exposure reduced Mg(++)-ATPase activity by 48.5% and increased Na+/K(+)-ATPase activity by 170%, while radiant heat caused no significant changes in either enzyme. Microwave exposure also decreased the ratio of saturated to unsaturated fatty acids, whereas radiant heat increased it. Membrane fluidity measured by EPR differed among sham, microwave, and radiant heat groups, reflecting the fatty acid changes.
Brown DO, Lu ST, Elson EC · 1994
Researchers studied microwave evoked body movements in mice using head and neck exposure to pulsed and gated continuous wave 1.25 GHz microwaves delivered via a resonant cavity. The incidence of body movements increased proportionally with specific absorption dose when the whole-body average specific absorption rate was held constant at 7300 W/kg, reaching a plateau at 0.9 kJ/kg. For doses higher than 0.9 kJ/kg, response incidence was proportional to the specific absorption rate and reached a plateau at 900 W/kg.
Lai H, Carino MA, Horita A, Guy AW, · 1994
Researchers exposed rats to pulsed 2450-MHz microwaves for 45 minutes at a power density of 1 mW/cm2 with a whole body specific absorption rate of 0.6 W/kg. This exposure decreased cholinergic activity in the hippocampus as measured by sodium-dependent high-affinity choline uptake. Microinjection of beta-funaltrexamine (1 microgram) into the septum before exposure blocked the microwave-induced decrease.
Singh N, Rudra N, Bansal P, Mathur R, Behari J, Nayar U · 1994
Researchers exposed Twenty-three days old rats to 2.45 GHz microwaves at 1.0 mW/cm2 for sixty days and measured poly ADPR polymerase activity in various organs. The enzyme activity increased by 20% in liver and 35% in testis, while it decreased by 53% in brain diencephalon and 20% in cortex. No change was observed in spleen and kidney, and the changes were accompanied by alterations in NAD+ levels.
Bergqvist B et al. · 1994
Researchers studied the effect of 2.45 GHz microwave radiation on the permeability of unilamellar phosphatidylcholine liposomes. Leakage of 5(6)-carboxyfluorescein was measured using spectrofluorimetry after exposure to microwaves or thermal heating for 5-20 min intervals. The microwave exposure did not result in any non-thermal increase in permeability above that produced by thermal heating. The study refutes earlier results that reported increased liposome permeability due to microwave exposure.
Krylova IN et al. · 1994
The study aimed to investigate the effect of ultrahigh-frequency electromagnetic radiation on learning and memory processes. Low-intensity electromagnetic field (12.6 cm, 2375 MHz, power density 1 mW/cm2) produced retrograde amnesia in the rat passive avoidance test. No effect was registered of microwave irradiation on the open field behavior and the pain sensitivity.
Yee KC, Chou CK, Guy AW · 1994
Researchers investigated the effect of microwave exposure on conduction velocity of frog ventricular muscle. Thirty-two frog hearts were divided into four groups and placed in temperature-controlled waveguides with Ringer's solution. One group served as control while three groups were exposed for 2 hours to pulsed 2,450 MHz microwave fields at SARs of 0.003, 2, and 6 W/kg. No significant difference in conduction velocity was found between control and exposed groups.
Akoev IG, Mel'nikov VM, Usachev AV, Kozhokaru AF, · 1994
Researchers studied whether exposure to low-intensity radiofrequency radiation after a lethal dose of gamma-radiation could modify the resulting injury in mice. The radiofrequency exposure lasted up to 23 hours at an intensity of 5 plus or minus 1.5 microwatts per square centimeter, covering frequency ranges of 2-8, 8-18, and 19-27 GHz with a swing frequency of 12-14 Hz. A clearly pronounced modification of acute radiation injury was obtained when the radiofrequency exposure was applied immediately after the gamma-radiation.
Somosy Z, Thuroczy G, Koteles GJ, Kovacs J · 1994
Researchers investigated the distribution and activity of Ca(2+)-ATPase in small intestine epithelial cells of mice after total body exposure to 2450 MHz microwave irradiation modulated at 16 Hz and X-ray irradiation. In control animals, enzyme activity was present in the brush border and lateral membranes, and lateral membrane activity was inhibited by quercetin. Microwave irradiation immediately decreased Ca(2+)-ATPase activity on lateral membranes, 1 Gy X-ray caused a similar reversible decrease within 24 hours, and 5 Gy X-ray reduced activity on both apical and lateral membranes persisting up to 24 hours.
Maes A, Verschaeve L, Arroyo A, De Wagter C, Vercruyssen L · 1993
Researchers exposed human peripheral blood lymphocytes to 2450 MHz microwaves for 30 and 120 minutes at constant body temperature. Exposure caused a marked increase in chromosome aberrations, including dicentric chromosomes and acentric fragments, and micronuclei. Microwave exposure did not influence cell kinetics or sister chromatid exchange frequency.
Litovitz TA, Krause D, Penafiel M, Elson EC, Mullins JM, · 1993
The study investigated the role of coherence time in the effect of microwaves on ornithine decarboxylase activity. Amplitude-modulated 915 MHz microwaves at SAR 2.5 W/kg modulated at 55, 60, or 65 Hz approximately doubled ornithine decarboxylase activity after 8 h, and switching modulation frequencies at coherence times of 1.0 s or less abolished the enhancement while times of 10 s or longer provided full enhancement.
Schwartz JL, Mealing GA · 1993
Researchers investigated the effects of AM or CW modulated 1 GHz exposure on calcium efflux and contractile force of isolated atrial muscle stripes of frog heart in vitro. Calcium efflux from electrically stimulated, 45Ca(2+)-preloaded atrial strips of the frog heart was measured from perfusate samples collected at 2-min intervals for 32 min while contractile force was simultaneously monitored. The atrial strips were exposed for 32 min to constant or amplitude-modulated 1 GHz fields at SAR ranging from 3.2 microW/kg to 1.6 W/kg with modulation at 0.5 Hz or 16 Hz. Neither unmodulated nor 0.5 Hz or 16 Hz modulated 1 GHz waves affected the movement of calcium ions or the contractile force in isolated atrial strips of the frog heart.
Field AS, Ginsburg K, Lin JC · 1993
Researchers studied the effects of pulsed microwaves on membrane input resistance and action potential interval statistics in spontaneously active ganglion neurons of land snails (Helix aspersa). Experiments were conducted at strictly constant temperature, so macroscopic heating was not responsible for any observed effects. Exposure significantly increased mean input resistance, while mean firing rate and mean input current were not affected. The net input current was found to be more variable in exposed neurons, though changes in interspike interval standard deviation and input current autocorrelation were not consistent across neurons.
Seaman RL, DeHaan RL · 1993
Researchers studied inter-beat intervals of aggregated cardiac cells from chicken embryos during 190-second exposures to 2.45 GHz microwaves. The inter-beat interval decreased during exposures at 42.0 W/kg and higher with continuous-wave or square-wave modulation, consistent with thermal effects. Increases occurred during continuous-wave exposures at 1.2-12.2 W/kg and decreases after pulse-modulated exposures at 8.4-12.2 W/kg, which were not consistent with simple thermal effects.
Krylov IN, Iasnetsov VV, Dukhanin AS, Pal'tsev IuP · 1993
Researchers exposed rats to microwaves at 2375 MHz with a power density of 1 mW/cm2 and found that this induced retrograde amnesia. The study found roles for opioidergic, benzodiazepine, GABAergic, and cholinergic components in the memory-impairing effects of microwaves. Piracetam and oxiracetam each prevented the negative effects of microwaves on memory processes in the rats.
Somosy Z, Thuroczy G, Kovacs J · 1993
Researchers investigated pyroantimonate-precipitable calcium in mouse intestinal epithelial cells after whole-body exposure to 2450 MHz continuous and 16 Hz square-modulated microwaves. Immediately after modulated irradiation at 0.5 and 1 mW/cm², calcium deposits rapidly appeared on the cytoplasmic side of lateral membranes and in the junctional complex including tight junctions. These changes were reversible, with calcium distribution returning to control-like patterns after 24 hours. Continuous-wave exposure at the same energy did not alter calcium distribution.
Verma M, Dutta SK. · 1993
The study aimed to investigate microwave induced alteration in neuron specific enolase gene expression. Researchers exposed pNGE7 cells containing the neuron specific enolase gene to 915 MHz, 16 Hz AM radiation at SAR 0.05 mW/kg. Exposure resulted in elevation of neuron specific enolase, a diagnostic marker for neuron and lung cancer. Ion-exchange chromatography separated neuron specific enolase activity from non-neuronal enolase activity and showed altered expression of both.
Rotkovska D, Bartonickova A, Kautska J · 1993
Lange DG, D'Antuono ME, Timm RR, Ishii TK, Fujimoto JM. · 1993
Pakhomov AG · 1993
Researchers investigated effects of 915 MHz pulsed microwave radiation with peak SAR 20-30 W/g on isolated frog nerve cords. Nerve heating did not exceed 2.2°C due to intense Ringer's solution perfusion. Irradiation during stimulation significantly decreased action potential amplitude and peak latency, while conventional heating increased amplitude, supporting a non-thermal mechanism.
Chou CK, Guy AW, Kunz LL, Johnson RB, Crowley JJ, Krupp JH · 1992
Two hundred male Sprague-Dawley rats were assigned in equal numbers to radiation-exposure and sham-exposure conditions, with exposure beginning at 8 weeks of age and continuing daily for 25 months. The experimental rats were exposed to 2,450-MHz pulsed microwaves at 800 pps with a 10-microseconds pulse width, square-wave modulated at 8-Hz. Blood samples were analyzed at regular intervals for serum chemistries, hematological values, protein electrophoretic patterns, thyroxine, and plasma corticosterone levels.
Lai H, Carino MA, Horita A, Guy AW, · 1992
Researchers investigated which opioid receptor subtypes mediate a microwave-induced decrease in central cholinergic activity in rats. Rats were pretreated with specific antagonists of mu, delta, and kappa opioid receptors before exposure to microwaves. All three receptor subtypes were involved in the decrease in cholinergic activity in the hippocampus.