ID Number		1972
Study Type		In Vitro
Model		Studies of membrane permeability in biological samples and models exposed to microwaves including mmwave frequencies.
Details		Cationic unilamellar liposomes loaded with carbonic anhydrase enzyme were exposed to 2450 MHz RF at 6 W/kg and analyzed for diffusion rate of the substrate p-nitrophenyl acetate across the liposome membrane (detected by color change upon CA conversion). The authors report a 2x increase in diffusion rate following 120 minutes of exposure that they state is not due to temperature effects. Subsequent studies showed a reduction in ascorbate oxidase activity at 5.6 W/kg, but no effect below that SAR level. The data suggested oligosaccharide chains of AO were critical to elicit the RF effect. Recently, the authors reported on single channel currents from rat neurons using ELF (50Hz) exposure. The authors report firing rate is modified by 50 Hz ELF exposure (biphasic) but not by 900 MHz RF. In related studies, the authors reported 130 GHz (PW at 7 Hz) decreased carbonic anhydrase enzymatic activity in loaded liposomes, but not when pulsed at either 5 or 10 Hz. Further, 53 GHz exposure to giant vesicles lead to permeability changes that the authors concluded were not due to temperature. AUTHORS' ABSTRACT: DAgostina, Ramundo-Orlando et al., 2018 (IEEE#6976): Among the many biological effects caused by low intensity extremely high frequency electromagnetic fields (EHF-EMF) reported in the literature, those on the nervous system are a promising area for further research. The mechanisms by which these fields alter neural activity are still unclear and thus far there appears to be no frequency dependence regarding neuronal responses. Therefore, proper in vitro models for preliminary screening studies of the interaction between neural cells with EMF are needed. We designed an artificial axon model consisting of a series of parallel RC networks. Each RC network contained an aqueous solution of lipid vesicles with a gradient of potassium (K+) concentration as the functional element. We investigated the effects of EHF-EMF (53.37 GHz39 mW) on the propagation of the electric impulse. We report that exposure to the EHF-EMF increases the amplitude of electrical signal by inducing a potassium efflux from lipid vesicles. Further, exposure to the EHF-EMF potentiates the action of valinomycin  a K+ carrier  increasing the extent of K+ transport across the lipid membrane. We conclude that exposure to the EHF-EMF facilitates the electrical signal propagation by increasing transmembrane potassium efflux, and that the model presented is promising for future screening studies of different EMF frequency spectrum bands.
Findings		Effects
Status		Completed With Publication
Principal Investigator		CNR, Rome Italy
Funding Agency		Agency Tech, Energy, Environ, Italy
Country		ITALY
References		Ramundo-Orlando, A et al. Biochim Biophys Acta, (2009) 1788:1497-1507 Ramundo-Orlando, A et al. Bioelectromagnetics, (2007) 28:587-598 Ramundo-Orlando, A et al. Bioelectromagnetics, (2004) 25:338-345 Bernardi, P et al. IEEE Trans. Biomed. Eng., (1994) 42:125-133 Orlando, AR et al. Bioelectromagnetics, (1994) 15:303-313 D'Agostino, S et al. Scientific Reports., (2018) 8:9299-
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