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Electromagnetic Fields in Biological Systems
in regeneration for both heads and tails, especially tails. The first appearance of eyes
occurred at day 7 posttransection in the tail portions exposed to the ELF-EMF. In
the sham control tail samples, the initial appearance of eyes occurred 48 hours later.
Concurrently, ELF-EMF-exposed heads and tails exhibited an elevation in the levels of
heat shock protein 70 (HSP70) protein, activation of an extracellular signal-regulated
kinase (ERK) cascade, and increase in the serum response factor (SRF)–serum response
element (SRE) binding. The authors concluded that this is accompanied by an increase
in HSP70 protein levels, activation of specific kinases, and upregulation of transcription
factors that are generally associated with repair processes.
Blackman (2006) raised the question of whether early exposure to EMFs can leave an
imprint on an organism that alters further development of the organism and results in
negative health consequences. This possibility deserves further experimental scrutiny.
3.3.1.5 Circulatory System Effects
Effects of magnetic fields including SMFs, ELF-EMFs, and PEMFs on the circulatory
system have been reviewed in experimental animals (Tenforde 2005; Saunders 2005;
McKay, Prato, and Thomas 2007; Ohkubo et al. 2007; Robertson et al. 2007; McNamee
et al. 2009; Ohkubo and Okano 2010) and in humans (Chakeres and de Vocht 2005;
Crozier and Liu 2005; van Rongen 2005; McKay, Prato, and Thomas 2007; Robertson
et al. 2007; McNamee et al. 2009). There are many therapeutic applications for locally
increased blood flow. It is suggested that magnetic fields have the potential to modify
microcirculatory perfusion. A recent review regarding the effects of magnetic fields on
microcirculation and microvasculature by McKay, Prato, and Thomas (2007) reported
that nearly half of the cited experiments (10/27) are related to vasodilatory effect,
increased blood flow, or increased blood pressure. Conversely, three of the total 27 studies reported a decrease in blood perfusion or pressure. Four studies reported no effect.
The remaining 10 studies found that magnetic fields could trigger either vasodilation or
vasoconstriction depending on the initial tone of the vessel. In terms of cellular effects
of magnetic fields related to perfusion, four of a total of 19 studies reported an increase
in NO activity from magnetic field exposures (one of these studies used a model with an
altered vessel state prior to exposure), one study found a biphasic effect, and five found
no effect. Nine studies reported vascular development effects (seven reported increased
angiogenesis, and two reported decreased angiogenesis). Other cellular effects were
reported in three studies.
For a human study with MRI, Gupta, Weeks, and Richie (2008) presented a mathematical approach of computing the elevation of the T-wave of an electrocardiography
(ECG) signal in an MRI bore caused by the flow of blood in the aorta. The elevation
was computed mathematically using the equations of magnetofluid dynamics (MFD).
A method was developed to measure MFD-induced voltage based on discretization of
the aortic arch and measurement of the blood flow profile in the aorta. The results were
compared to the ECG signals measured in humans in the bore of a 1.5-T imaging magnet (1.5-T SMF alone). The computed ECG signals at the 12 leads were very similar to
the measured values.
McNamee et al. (2010, 2011) suggested that ELF-EMFs (60 Hz, 0.2 and 1.8 mT) did
not affect perfusion, heart rate, or mean arterial pressure. The decrease in perfusion and
Electromagnetic Fields in Biological Systems
in regeneration for both heads and tails, especially tails. The first appearance of eyes
occurred at day 7 posttransection in the tail portions exposed to the ELF-EMF. In
the sham control tail samples, the initial appearance of eyes occurred 48 hours later.
Concurrently, ELF-EMF-exposed heads and tails exhibited an elevation in the levels of
heat shock protein 70 (HSP70) protein, activation of an extracellular signal-regulated
kinase (ERK) cascade, and increase in the serum response factor (SRF)–serum response
element (SRE) binding. The authors concluded that this is accompanied by an increase
in HSP70 protein levels, activation of specific kinases, and upregulation of transcription
factors that are generally associated with repair processes.
Blackman (2006) raised the question of whether early exposure to EMFs can leave an
imprint on an organism that alters further development of the organism and results in
negative health consequences. This possibility deserves further experimental scrutiny.
3.3.1.5 Circulatory System Effects
Effects of magnetic fields including SMFs, ELF-EMFs, and PEMFs on the circulatory
system have been reviewed in experimental animals (Tenforde 2005; Saunders 2005;
McKay, Prato, and Thomas 2007; Ohkubo et al. 2007; Robertson et al. 2007; McNamee
et al. 2009; Ohkubo and Okano 2010) and in humans (Chakeres and de Vocht 2005;
Crozier and Liu 2005; van Rongen 2005; McKay, Prato, and Thomas 2007; Robertson
et al. 2007; McNamee et al. 2009). There are many therapeutic applications for locally
increased blood flow. It is suggested that magnetic fields have the potential to modify
microcirculatory perfusion. A recent review regarding the effects of magnetic fields on
microcirculation and microvasculature by McKay, Prato, and Thomas (2007) reported
that nearly half of the cited experiments (10/27) are related to vasodilatory effect,
increased blood flow, or increased blood pressure. Conversely, three of the total 27 studies reported a decrease in blood perfusion or pressure. Four studies reported no effect.
The remaining 10 studies found that magnetic fields could trigger either vasodilation or
vasoconstriction depending on the initial tone of the vessel. In terms of cellular effects
of magnetic fields related to perfusion, four of a total of 19 studies reported an increase
in NO activity from magnetic field exposures (one of these studies used a model with an
altered vessel state prior to exposure), one study found a biphasic effect, and five found
no effect. Nine studies reported vascular development effects (seven reported increased
angiogenesis, and two reported decreased angiogenesis). Other cellular effects were
reported in three studies.
For a human study with MRI, Gupta, Weeks, and Richie (2008) presented a mathematical approach of computing the elevation of the T-wave of an electrocardiography
(ECG) signal in an MRI bore caused by the flow of blood in the aorta. The elevation
was computed mathematically using the equations of magnetofluid dynamics (MFD).
A method was developed to measure MFD-induced voltage based on discretization of
the aortic arch and measurement of the blood flow profile in the aorta. The results were
compared to the ECG signals measured in humans in the bore of a 1.5-T imaging magnet (1.5-T SMF alone). The computed ECG signals at the 12 leads were very similar to
the measured values.
McNamee et al. (2010, 2011) suggested that ELF-EMFs (60 Hz, 0.2 and 1.8 mT) did
not affect perfusion, heart rate, or mean arterial pressure. The decrease in perfusion and