Journal
BIOELECTROCHEMISTRY
Volume 52, Issue 1, Pages 9-16Publisher
ELSEVIER SCIENCE SA
DOI: 10.1016/S0302-4598(00)00076-3
Keywords
electromagnetic; threshold; embryo; hypoxia; heat shock protein; sigmoid
Funding
- NIEHS NIH HHS [5 R01 ES06872-02] Funding Source: Medline
Ask authors/readers for more resources
We have recently reported that weak electromagnetic (EM) field exposure of chick embryos induces a response that can be used to protect against subsequent hypoxic insult. This work is continued here with an exposure response study using 20-min exposure to 60 Hz magnetic fields over a range of 2-10 muT. Once again, the biomarker used was induction of hypoxia protection. A sigmoidal response curve was found, with exposures to magnetic field strengths greater than or equal to 4 muT inducing maximum hypoxia protection (68% survival). We also attempted to determine whether the magnetic or induced electric component of the EM field was responsible for the observed protection. This was accomplished by making measurements with two different orientations of the magnetic fields (perpendicular and parallel to the major axis of the egg). Owing to the configuration of the embryo in the egg, the induced electric field at the embryo was lower when the magnetic field was parallel to the major axis even though the magnetic field strength was the same for each orientation. Exposure of the embryos to the parallel orientation resulted in a reduced protective response. An exposure-response curve generated for this orientation of the field also showed a more drawn-out appearance, consistent with the observed distribution of embryo positions within the egg. Our results suggest, that the induced electric, not the applied magnetic field, plays a primary role in the protective effect observed in this chick embryo model. (C) 2000 Elsevier Science S.A. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available