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.
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.
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.
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.
Rotkovska D, Bartonickova A, Kautska J · 1993
Lange DG, D'Antuono ME, Timm RR, Ishii TK, Fujimoto JM. · 1993
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.
Lai H, Carino MA, Horita A, Guy AW · 1992
Researchers exposed rats to single 45-minute and repeated daily 45-minute microwave sessions at 2450 MHz, 1 mW/cm², with a whole-body SAR of 0.6 W/kg. After a single exposure, receptor concentration increased in the cerebral cortex but not in the hippocampus or cerebellum. No significant change in binding affinity of the receptors was observed in any of the brain regions studied. After repeated exposures, no significant change in receptor concentration was found in the cerebral cortex. Handling and exposure procedures did not significantly affect benzodiazepine receptors.
Kues HA et al. · 1992
Researchers exposed anesthetized monkeys to pulsed 2.45 GHz microwaves after topical treatment with timolol maleate or pilocarpine. Drug pretreatment lowered the power-density threshold for corneal endothelial lesions and increased iris vascular permeability from 10 to 1 mW/cm². Effects occurred at an average SAR of 0.26 W/kg and were confirmed with specular microscopy, fluorescein angiography, and horseradish peroxidase tracer techniques.
Czerska EM, Elson EC, Davis CC, Swicord ML, Czerski P · 1992
Researchers exposed human lymphocytes in vitro for 5 days to continuous-wave (CW) or pulsed-wave (PW) 2450-MHz radiation at non-heating and heating levels, with actual average SARs ranging to 12.3 W/kg. At non-heating levels, CW exposure did not affect spontaneous lymphoblastoid transformation, but PW exposure enhanced it significantly (P less than .002). At heating levels, PW exposure enhanced transformation to a greater extent than either conventional heating or CW heating, a finding significant at the .02 level.
Phelan AM, Lange DG, Kues HA, Lutty GA · 1992
Researchers exposed B16 melanoma cells to 2.45-GHz pulsed microwaves at 10 mW/cm² for 1 hour and measured membrane ordering using electron paramagnetic resonance. The exposure shifted the cell membrane from a more fluid-like phase to a more solid, ordered state. Similar membrane ordering occurred in melanin-reconstituted liposomes, but not in amelanotic cells or liposomes without melanin. Superoxide dismutase inhibited the microwave-induced ordering, implicating oxygen radicals as a cause.
Inaba R, Shishido K, Okada A, Moroji T. · 1992
Maillefer RH, Quock RM · 1992
Male Swiss Webster mice were exposed to 10, 15, and 20 mW/cm2 RFR at 2450 MHz for 10 minutes at SARs of 23.7, 34.6, and 45.5 W/kg, then tested in the abdominal constriction paradigm. Confinement alone did not appreciably alter body temperature but appeared to induce stress-associated analgesia that was not blocked by naltrexone. RFR exposure raised body temperature and further increased analgesia in an SAR-dependent manner. The high SAR-induced analgesia was blocked by naltrexone, but the hyperthermia was not.
Fukui Y, Hoshino K, Inouye M, Kameyama Y · 1992
Researchers exposed pregnant mice to 2.45 GHz microwave radiation for 15 or 20 minutes on day 13 of gestation. Pyknotic cell incidence in the ventricular zone was 1.83% after 15 minutes and 3.06% after 20 minutes of microwave exposure. Microwave radiation for 20 minutes produced effects comparable to immersion in 42°C hot water for 15 minutes. Brain weight was significantly lower and neuron density higher in the 20-minute exposure group compared to controls. The researchers concluded that microwave radiation at the tested dose mainly has a thermal effect.
Veyret B et al. · 1991
French researchers exposed mice to low-power pulsed microwaves (similar to radar frequencies) for 10 hours daily over five days to test effects on immune system function. They found that simple pulsed signals had little effect, but when the signals included additional amplitude modulation, the mice showed significant changes in antibody production - some frequencies strengthened immune responses while others weakened them.
Ciaravino V, Meltz ML, Erwin DN · 1991
Researchers exposed Chinese hamster ovary cells to adriamycin and pulsed RFR at 2,450 MHz and 33.8 W/Kg for 2 h. The maximal temperature in the tissue-culture medium was 39.7 +/- 0.2 degrees C. The experiments were controlled for chemical and RFR exposures as well as for temperature. Verified statistically, the data indicate that the RFR did not affect changes in cell progression caused by adriamycin and did not change the number of sister chromatid exchanges induced by adriamycin.
Garson OM, McRobert TL, Campbell LJ, Hocking BA, Gordon I. · 1991
Researchers studied chromosome damage in 38 radio-linemen exposed to radio-frequency radiation and 38 matched controls. They analyzed Two hundred metaphases per person, scored blind, and found the rate of aberrant cells was the same in both groups. There were no statistically significant differences in the types of chromosome aberrations.
Lai H, Carino MA, Wen YF, Horita A, Guy AW · 1991
Rats were repeatedly exposed to pulsed, circularly polarized microwaves at 2,450 MHz with 2-microsecond pulses at 500 pps, a power density of 1 mW/cm², and a whole-body SAR of 0.6 W/kg. Ten 45-minute sessions increased muscarinic cholinergic receptor concentration in the hippocampus, while ten 20-minute sessions decreased concentration in the frontal cortex and hippocampus. Pretreatment with naltrexone at 1 mg/kg IP before each exposure session blocked these microwave-induced changes in cholinergic receptors.
Lange DG, Sedmak J · 1991
Microwave exposure produced a dose-dependent increase in JEV-induced lethality. Hypercarbia at 5, 10, and 20% CO2 also produced a dose-dependent increase in JEV-induced lethality.
