Influence of exposure to electromagnetic field on the cardiovascular system

Abstract

1 We examined whether extremely low frequency electromagnetic fields (ELF-EMF) affect the basal level of cardiovascular parameters and influence of drugs acting on the sympathetic nervous system. 2 Male rats were exposed to sham control and EMF (60 Hz, 20 G) for 1 (MF-1) or 5 days (MF-5). We evaluated the alterations of blood pressure (BP), pulse pressure (PP), heart rate (HR), and the PR interval, QRS interval and QT interval on the electrocardiogram and dysrhythmic ratio in basal level and dysrhythmia induced by beta-adrenoceptor agonists. 3 In terms of the basal levels, there were no statistically significant differences among control, MF-1 and MF-5 in PR interval, QRS interval, mean BP, HR and PP. However, the QT interval, representing ventricular repolarization, was significantly reduced by MF-1 (P < 0.05). 4 (-)-Dobutamine (beta1-adrenoceptor-selective agonist)-induced tachycardia was significantly suppressed by ELF-EMF exposure in MF-1 for the increase in HR (DeltaHR), the decrease in QRS interval (DeltaQRS) and the decrease in QT (DeltaQT) interval. Adrenaline (nonselective beta-receptor agonist)-induced dysrhythmia was also significantly suppressed by ELF-EMF in MF-1 for the number of missing beats, the dysrhythmic ratio, and the increase in BP and PP. 5 These results indicated that 1-day exposure to ELF-EMF (60 Hz, 20 G) could suppress the increase in HR by affecting ventricular repolarization and may have a down-regulatory effect on responses of the cardiovascular system induced by sympathetic agonists.

Radical Scavengers Suppress Low Frequency EMF Enhanced Proliferation in Cultured Cells and Stress Effects in Higher Plants

“…One of the most controversial issues regarding the effects of weak magnetic fields at low frequencies on biological systems is the lack of any widely accepted physico-chemical mechanism to account for the observed phenomena: increased cell proliferation, DNA mutation, altered lipid-protein interactions, biochemical reactions involving free radicals, tumor promotion, Ca 2+ signaling, ornithine decarboxylase activity, gene expression, src kinase activity, the involvement of melatonin and Na + /K + -ATPase, peroxidase activity, fluid-phase endocytosis, connexin32 hemi channels, effects on the cardiovascular system, as well as interaction at the level of the signaling manifold in general and NO radicals in particular (Antov et al, 2004;Portaccio et al, 2005;Ramundo-Orlando et al, 2005;Mahrour et al, 2005;Jeong et al, 2005;Kleinerman et al, 2005) & see the literature survey in .…”

A literature review: the cardiovascular effects of exposure to extremely low frequency electromagnetic fields

“…Despite reporting changes in EEG activity (alpha 8-13 Hz) in the 80 T group and of pain threshold changes in the 40 T group, no eVect of exposure could be determined for HR or blood pressure in any of the exposure groups (Ghione et al 2005). Jeong et al (2005) examined the eVects of exposure to a 60 Hz, 2 mT Weld using rats maintained in an experimental chamber for either 1 or 5 days. They found no eVect of exposure on blood pressure in either of the exposure duration groups, although a 1 day exposure was associated with the suppression of pharmacologically induced tachycardia and dysrhythmia.…”

ANTI-HYPERCHOLESTEROLEMIA ACTIVITY OF ETHANOL EXTRACT Peperomia pellucid

“…Atherosclerosis is a progressive disease characterized by the accumulation cholesterol, low density lipoprotein (LDL), and fibrous elements in the large arteries that contribute to the severity of cardiovascular disease (Farias, 1996;Jeong, 2005). Increased total cholesterol and triglycerides are the factors causing the development of atherosclerosis and coronary heart disease (Farias, 1996;Jeong, 2005;Chobanian, 1991).…”

“…Increased total cholesterol and triglycerides are the factors causing the development of atherosclerosis and coronary heart disease (Farias, 1996;Jeong, 2005;Chobanian, 1991).…”