ABSTRACT
Objective To study the combined effect of extremely low frequency electromagnetic fields ( ELF-EMF ) exposure (50 Hz and 3 mT) and high temperature exposure on hsp22 and hsp26 expression in Drosophila melanogaster. Methods Under the conditions of 50 Hz and 3 mT ELF-EMF,the male and female D.melanogaster was separately exposed for 2 h at 25℃, 27.5℃, 30℃, 32.5℃,and 35℃, respectively.The death rate, exercise capacity and the hsp22 and hsp26 expression levels of D.melanogaster were detected after exposure;or at 25℃and 35℃at 2 h, 4 h, 8 h, and 24 h, respectively.The hsp22 and hsp26 expression levels of D.melanogaster were tested after exposure .Results After exposure for 2 h at 25℃, 27.5℃, 30℃, 32.5℃, and 35℃, temperature had a significant effect (P0.05).After exposure for 2 h at 25℃, 27.5℃, 30℃, 32.5℃, and 35℃, the hsp22 and hsp26 expression levels of D.melanogaster were significantly impacted(P<0.01) by gender, temperature, ELF-EMF and exposure time, and tem-perature was the most important factor .Gender, temperature, ELF-EMF and exposure time had some interaction with the results.Conclusion ELF-EMF can influence the expression levels of hsp22 and hsp26.ELF-EMF exposure contributes to heat tolerance in D.melanogaster through accelerated expression of hsp22 and hsp26.
ABSTRACT
Adult rats were subjected to the combined stress of low atmospheric pressure and temperature at a simulated altitude of 7620 metres and at 5°C for 5 hours. A significant increase in the influx of rubidium-86 and the efflux of sodium-22 was observed in erythrocytes of experimental rats in vitro. Blood 2,3-diphosphoglycerate was appreciably enhanced while blood sodium and reduced glutathione contents in the experimental animals remained unchanged.