Extremely low frequency electromagnetic fields and heat shock can increase microvesicle motility in astrocytes

• Published in: Bioelectromagnetics 2001-02, Vol.22 (2), p.71-78
• Main Authors: Gölfert, F., Hofer, A., Thümmler, M., Bauer, H., Funk, R.H.W.
• Format: Article
• Language: English
• Subjects: Animals; Astrocytes - physiology; Astrocytes - ultrastructure; Cells, Cultured; Electromagnetic Fields - adverse effects; Heat-Shock Response - physiology; Image Processing, Computer-Assisted; Microscopy, Video; Movement - physiology; Organelles - physiology; Organelles - ultrastructure; Rats; stress; video-enhanced contrast microscopy; vital dyes
• ISSN: 0197-8462; 1521-186X
• DOI: 10.1002/1521-186X(200102)22:2<71::AID-BEM1008>3.0.CO;2-I

The effect of extremely low frequency electromagnetic fields (EMF) on microvesicles was examined in rat astrocytes by video‐enhanced microscopy in combination with a perfusable cell chamber. The EMF effect was compared with the effect of heat shock (HS) and with a combination of them both. The velocity of microvesicles was measured using image processing software (NIH Scion image 1.61). After exposure of astrocytes to EMF (50 Hz, 100μT, 1 h), the velocity of microvesicles in astrocytes increased from 0.32 ± 0.03 μm/s (n = 120, 95% CI) in the untreated control group to 0.41 ± 0.03 μm/s (n = 175, 95% CI). Fifteen minutes after HS (45°C, 10 min) the microvesicles showed a velocity of 0.56 ± 0.03 μm/s (n = 125, 95% CI). Combination of HS and EMF led to an increase in velocity up to 0.54 ± 0.03 μm/s (n = 110, 95% CI). No significant difference between HS and HS+EMF was found. Compared to the untreated control group, the increased microvesicle velocity of the exposed cells might be a stress response of the cell. It is possibly a sign of intensified intracellular traffic required to adjust the metabolic needs. Bioelectromagnetics 22:71–78, 2001. © 2001 Wiley‐Liss, Inc.