Electromagnetic fields and the blood-brain barrier.
نویسنده
چکیده
The mammalian blood-brain barrier (BBB) consists of endothelial cells, linked by tight junctions, and the adjoining pericytes and extracellular matrix. It helps maintain a highly stable extracellular environment necessary for accurate synaptic transmission and protects nervous tissue from injury. An increase in its normally low permeability for hydrophilic and charged molecules could potentially be detrimental. Methods to assess the permeability of the BBB include histological staining for marker molecules in brain sections and measurement of the concentration of marker molecules in blood and brain tissue. Their advantages and disadvantages are discussed. Exposure to levels of radiofrequency electromagnetic fields (EMF) that increase brain temperature by more than 1°C can reversibly increase the permeability of the BBB for macromolecules. The balance of experimental evidence does not support an effect of 'non-thermal' radiofrequency fields with microwave and mobile phone frequencies on BBB permeability. Evidence for an effect of the EMF generated by magnetic resonance imaging on permeability is conflicting and conclusions are hampered by potential confounders and simultaneous exposure to different types and frequencies of EMF. The literature on effects of low frequency EMF, which do not cause tissue heating, is sparse and does not yet permit any conclusions on permeability changes. Studies on the potential effect of EMF exposure on permeability of the BBB in humans are virtually absent. Future permeability studies should focus on low frequency effects and effects in humans. Care should be taken to avoid the methodological limitations of earlier studies and to determine the pathophysiological relevance of any changes found.
منابع مشابه
Radiofrequency and extremely low-frequency electromagnetic field effects on the blood-brain barrier.
During the last century, mankind has introduced electricity and during the very last decades, the microwaves of the modern communication society have spread a totally new entity--the radiofrequency fields--around the world. How does this affect biology on Earth? The mammalian brain is protected by the blood-brain barrier, which prevents harmful substances from reaching the brain tissue. There i...
متن کاملCancers of the Brain and CNS: Global Patterns and Trends in Incidence
Miranda-Filho et al. in their recently published paper entitled “Cancers of the brain and CNS: global patterns and trends in incidence†provided a global status report of the geographic and temporal variations in the incidence of brain and CNS cancers in different countries across continents worldwide. While the authors confirm the role of genetic risk factors and ionizing radiation exposur...
متن کاملNerve cell damage in mammalian brain after exposure to microwaves from GSM mobile phones.
The possible risks of radio-frequency electromagnetic fields for the human body is a growing concern for our society. We have previously shown that weak pulsed microwaves give rise to a significant leakage of albumin through the blood-brain barrier. In this study we investigated whether a pathologic leakage across the blood-brain barrier might be combined with damage to the neurons. Three group...
متن کاملElectromagnetic Fields of Mobile Phone Jammer Exposure on Blood Factors in Rats
Background: The increasing demand for using mobile phones has led to increasing mobile phone jammers as well. On the other hand, reports show that exposure to electromagnetic field causes an increase in the incidence of diseases such as leukemia, cancer, depression and failure in pregnancy outcomes; therefore, the aim of this study is to investigate the effects of exposure to electromagnetic fi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Brain research reviews
دوره 65 1 شماره
صفحات -
تاریخ انتشار 2010