Electromagnetic fields (1.8 GHz) increase the permeability to sucrose of the blood-brain barrier in vitro

We report an investigation on the influence of high frequency electromagnet ic fields (EMF) on the permeability of an in vitro model of the blood-brain barrier (BBB). Our model was a co-culture consisting of rat astrocytes and porcine brain capillary endothelial cells (BCEC). Samples were characteriz ed morphologically by scanning electron microscopy and immunocytochemistry. The BBB phenotype of the BCEC was shown by the presence of zona occludens protein (ZO-1) as a marker for tight junctions and the close contact of the cells together with the absence of intercellular clefts. Permeability meas urements using C-14-sucrose indicated a physiological tightness which corre lated with the morphological findings and verified the usefulness of our in vitro model. Samples were exposed to EMF conforming to the GSM1800-standar d used in mobile telephones (1.8 GHz). The permeability of the samples was monitored over four days and compared with results of samples that were cul tured identically but not exposed to EMF Exposure to EMF increased permeabi lity for C-14-sucrose significantly compared to unexposed samples. The unde rlying pathophysiological mechanism remains to be investigated. (C) 2000 Wi ley-Liss, Inc.