Mausset A, de Seze R, Montpeyroux F, Privat A · 2001
Researchers injected rats with gamma-vinyl-GABA to increase GABA levels and then used immunohistochemistry and image analysis to measure cerebellar GABA content. They exposed rats to 900 MHz pulsed radiofrequency at 4 W/kg SAR and continuous waves at 32 W/kg SAR. Pulsed exposure selectively reduced the stained processes area in the Purkinje cell layer, while continuous exposure decreased optical density in all three cell layers. The authors noted that it is unknown whether these effects are partly due to local tissue heating.
Lushnikov et al. · 2001
Researchers exposed healthy male NMRI mice to 42.0 GHz electromagnetic radiation at an energy flux density of 0.15 mW/cm2 under several different exposure regimes. After repeated exposures for 20 days before immunization, thymic cellularity was reduced by 17.5% and spleen cellularity by 14.5%, both statistically significant. The humoral immune response itself did not change significantly under any of the exposure regimes tested.
Finnie JW et al. · 2001
Researchers studied the effect of GSM radiofrequency fields on vascular permeability in the mouse brain using an exposure system operating at 898.4 MHz. Mice were given a single whole-body exposure for 60 minutes at a specific absorption rate of 4 W/kg, while control mice were sham-exposed or permitted free movement in a cage. No significant difference in albumin extravasation was detected between any of the groups.
Simkó M, Droste S, Kriehuber R, Weiss DG · 2001
Researchers examined the effects of 50 Hz electromagnetic fields on phagocytosis and free radical production in mouse bone marrow-derived macrophages exposed in vitro to magnetic field densities of 0.5 to 1.5 mT. Short-time exposure of 45 minutes resulted in a significantly increased phagocytic uptake of 36.3% plus or minus 15.1%, as measured by the internalization rate of latex beads. A significant increase in superoxide production was also detected after exposure to electromagnetic fields. Because co-exposure to electromagnetic fields and TPA showed no additive increase in bead uptake, researchers concluded that the electromagnetic fields-induced stimulation does not involve the protein kinase C signal transduction pathway.
Jajte J, Zmyślony M, Palus J, Dziubałtowska E, Rajkowska E. · 2001
Researchers used the alkaline comet assay to assess DNA damage in rat peripheral blood lymphocytes exposed in vitro to iron ions and a 50 Hz magnetic field. Cell samples were incubated for 3 hours in Helmholtz coils at 7 mT 50 Hz, and some were treated with ferrous chloride at 10 μg/ml during that exposure. A significant increase in cells with DNA damage was found only after simultaneous exposure to ferrous chloride and the 7 mT 50 Hz magnetic field, compared to control samples or those incubated with ferrous chloride alone. When cells were treated with melatonin before that combined exposure, the number of damaged cells was significantly reduced, with the reduction reaching about 50% at 0.5 mM and about 100% at 1.0 mM.
Sykes PJ, McCallum BD, Bangay MJ, Hooker AM, Morley AA. · 2001
Researchers studied the effect of pulsed 900 MHz radiofrequency radiation at 4 W/kg on somatic intrachromosomal recombination in the spleen of pKZ1 mice. Mice were exposed daily for 30 minutes to 900 MHz fields for 1, 5, or 25 days, and spleen sections were screened for DNA inversion events three days after the last exposure. There was no significant difference between control and treated groups in the 1- and 5-day exposure groups, but a significant reduction in inversions was found in the 25-day group.
Unknown authors · 2000
Unknown authors · 2000
Researchers from Löscher's group in Germany exposed Sprague-Dawley rats to 50-Hz magnetic fields at microtesla flux densities for 13 or 27 weeks using a DMBA breast cancer model. The exposure significantly increased mammary tumor development and growth in those experiments. A similar study by Battelle in the United States did not replicate the effect.
Tsurita G, Nagawa H, Ueno S, Watanabe S, Taki M, · 2000
Male Sprague-Dawley rats were exposed to a 1439 MHz TDMA field. Exposure lasted one hour a day for two or four weeks. The study assessed blood-brain barrier permeability, cerebellar morphology, and body mass.
Sienkiewicz ZJ et al. · 2000
Marino C et al. · 2000
Researchers examined possible effects of 900 MHz microwave exposure on the cochlear epithelium of rats. Two experiments used male Sprague-Dawley rats with far-field exposure in a cubic chamber. No statistically significant evidence was obtained at both SAR values. The exposure system and diagnostic apparatus were considered useful for investigating auditory effects, but no evidence was observed with the parameters applied.
Jauchem JR, Ryan KL, Freidagger MR · 2000
Ketamine-anesthetized male Sprague-Dawley rats were exposed to 1 GHz, 10 GHz, or combined 1 and 10 GHz microwaves at a whole-body specific absorption rate of 12 W/kg. Exposures were conducted in E and H orientations under far-field conditions until lethal temperatures were reached. Survival time was shortest at 1 GHz, intermediate for combined frequencies, and longest at 10 GHz, with most differences statistically significant. Temperature values at most sites for combined exposure fell between those of the single-frequency groups. Arterial blood pressure initially increased then decreased until death, heart rate increased throughout, and patterns were similar across all groups.
Yoshikawa T et al. · 2000
Sidorenko A, Tsaryuk V · 2000
Researchers studied the effects of microwave radiation and strychnine on cerebral biopotentials in narcotized rats. Strychnine and microwave radiation produced changes in spectral parameters of electrocorticogram, correlation dimension, and Kolmogorov entropy opposite to those induced by urethane.
Schirmacher A et al. · 2000
Mezhevikina LM, Khramov RN, Lepikhov KA · 2000
Researchers cultured two-cell mouse embryos in vitro and exposed them to electromagnetic irradiation in the millimeter range. After 30 min of exposure, the embryos acquired the ability to develop on their own and could reach the stage of blastocyst in 150 microliters of Whitten cultural medium without serum or growth factors. The authors proposed that millimeter range electromagnetic waves activate metabolic processes and specifically the synthesis of factors controlling early embryonic development in culture.
Imaida K et al. · 2000
Researchers gave six-week-old male F344 rats a single dose of diethylnitrosamine and then treated them with melatonin at 0, 1, 5, 10, and 20 ppm in drinking water for six weeks. Melatonin was administered only during the night to maintain circadian rhythm. At week 3, rats underwent partial hepatectomy, and at week 8 they were sacrificed and serum hormone levels were measured. Serum melatonin was elevated while luteinizing hormone and testosterone were reduced. The number and area of GST-P-positive liver foci decreased in melatonin-treated groups, significantly for number at 10 ppm.
Wang, BM, Lai, H · 2000
Rats were trained in six sessions to locate a submerged platform in a circular water maze. They were exposed to pulsed 2450-MHz microwaves for 1 hour before each training session. Microwave-exposed rats were slower than sham-exposed and cage control rats in learning to locate the platform. During the probe trial, microwave-exposed animals spent significantly less time in the quadrant that had contained the platform. There was no significant difference in swim speed among the three groups.
Olchowik G, Maj JG · 2000
Researchers investigated the influence of microwave irradiation on gamma-glutamyl transpeptidase activity induced by hydrocortisone in rat liver. Rats received hydrocortisone at 20 mg/kg for 60 days and were exposed to microwave radiation at 53.57 GHz with power densities of 10 mW/cm2 and 1 mW/cm2 during and after treatment. The results indicate that microwave radiation may block the hydrocortisone-induced effect on GGT activity, and this blocking effect depends on the power density of the millimetre microwaves.
Nakamura H, Nagase H, Ogino K, Hatta K, Matsuzaki I · 2000
Researchers exposed rats to continuous-wave microwaves at 2 mW/cm² and 2450 MHz for 90 minutes and measured uteroplacental blood flow and hormone levels. Colonic temperature did not change significantly in either virgin or pregnant rats. Microwave exposure decreased uteroplacental blood flow and increased progesterone and PGF2α in pregnant rats but not in virgin rats. Pretreatment with angiotensin II prevented these changes in pregnant rats. Corticosterone increased and estradiol decreased during exposure regardless of pregnancy status or angiotensin II pretreatment.
Dasdag S; Akdag MZ; Ayy ld z O et al. · 2000
Researchers studied the effects of microwaves emitted by cellular phones on peripheral blood parameters and birth weights of rats. The birth weight of offspring in the experimental group was significantly lower than in the sham-exposed group (p < 0.001). No blood parameters differed following exposure, and rectal temperatures showed no significant differences between groups. All parameters investigated were normal in the next generation of rats.
Cobb BL et al. · 2000
Researchers exposed pregnant rats to UWB electromagnetic fields during gestation days 3-18, with some pups also exposed for 10 days after birth, then evaluated offspring for behavioral, functional, and morphological effects. UWB-exposed pups emitted significantly more stress vocalizations than sham-exposed pups, and the medial-to-lateral length of the hippocampus was significantly longer in UWB-exposed pups than in sham-exposed animals. Researchers noted there does not appear to be a unifying physiological or behavioral relationship among the significant differences observed.
Adey WR et al. · 2000
Researchers exposed Fischer 344 rats to a frequency-modulated signal at 836.55 MHz in a two-year bioassay, testing for effects on spontaneous and chemically induced central nervous system tumors. The study used six groups of offspring totaling 540 rats, with some groups receiving the chemical ENU and others sham or field exposure. No FM field-mediated changes were observed in number, incidence, or histological type of either spontaneous or ENU-induced brain tumors, nor were gender differences detected in tumor numbers.
Noda Y, Mori A, Liburdy RP, Packer L · 2000
Researchers investigated the effect of pulsed magnetic fields on nitric oxide synthase (NOS) activity in the rat brain. A significant increase in NOS activity was observed in the cerebellum at 111.2±2.0% (P<0.05) for a 1 Gauss (0.1 mT) pulsed DC field, across five separate experiments. Neither AC nor static DC field treatment showed any significant change in NOS activity. In the hippocampus, cortex, medulla oblongata, hypothalamus, striatum, and midbrain, only a slight change or no effect was observed.
Unknown authors · 1999
Researchers studied DNA migration using the comet assay in brain cells of CBA mice exposed continuously to 50 Hz, 0.5 mT magnetic fields for 2 hours, 5 days, or 14 days. No differences were observed in mice exposed for 2 hours or 5 days compared with controls. Mice exposed for 14 days showed significantly extended DNA migration (0.02 < p < 0.05).
