Exposure to extremely low frequency electromagnetic fields alters the behaviour, physiology and stress protein levels of desert locusts.
Electromagnetic fields (EMFs) are present throughout the modern world and are derived from many man-made sources including overhead transmission lines. The risks of extremely-low frequency (ELF) electromagnetic fields are particularly poorly understood especially at high field strengths as they are rarely encountered at ground level. Flying insects, however, can approach close to high field strength transmission lines prompting the question as to how these high levels of exposure affect behaviour and physiology. Here we utilise the accessible nervous system of the locust to ask how exposure to high levels of ELF EMF impact at multiple levels. We show that exposure to ELF EMFs above 4 mT leads to reduced walking. Moreover, intracellular recordings from an identified motor neuron, the fast extensor tibiae motor neuron, show increased spike latency and a broadening of its spike in exposed animals. In addition, hind leg kick force, produced by stimulating the extensor tibiae muscle, was reduced following exposure, while stress-protein levels (Hsp70) increased. Together these results suggest that ELF EMF exposure has the capacity to cause dramatic effects from behaviour to physiology and protein expression, and this study lays the foundation to explore the ecological significance of these effects in other flying insects.
Department of Biophysics, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland.
Joanna
J
Wyszkowska
Centre for Biological Sciences, University of Southampton, Southampton.
Sebastian
S
Shepherd
Engineering Sciences, University of Southampton, Southampton, UK.
Suleiman
S
Sharkh
Centre for Biological Sciences, University of Southampton, Southampton.
Christopher W
CW
Jackson
Centre for Biological Sciences, University of Southampton, Southampton.
Philip L
PL
Newland
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects*; D004574:Electromagnetic Fields; D006110:Grasshoppers / Q000378:metabolism* / Q000528:radiation effects; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D019476:Insect Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000502:physiology / Q000528:radiation effects; D009474:Neurons / Q000502:physiology / Q000528:radiation effects; D013696:Temperature; D015854:Up-Regulation / Q000187:drug effects
D018840:HSP70 Heat-Shock Proteins; D019476:Insect Proteins