Pregnant rats were divided into four groups: 1) prenatal exposure to the electric field and postnatal sham exposure, 2) prenatal sham exposure and postnatal exposure, 3) prenatal and postnatal exposure and 4) only sham exposure (control group). After 22 days, young animals were separated from their mothers and after further 68 days, they were killed and investigated. Each group included 10 female rats which were taken from 10 mothers.
Exposure duration: daily for 1 hour/day every during pregnancy
Exposure duration: daily for 1 hour/day for 90 days after birth
Exposure duration: daily for 1 hour/day during pregnancy and for 90 days after birth
|Chamber||plastic cage (42.5 cm x 26.5 cm x 18.5 cm)|
|Setup||plate capacitor consisted of parallel copper plates (50 x 80 cm) plated with zinc (2 mm thickness); in order to produce uniform field, the comers of parallel plates were rounded; plates were placed upright on wooden stands and positioned parallel to each other at 50 cm distance; cables were connected to the center of the plates on their outer surfaces to preserve field homogeneity; the plastic cage was placed in the center between the two plates at equal distance; four animals in one cage were exposed at one time and could move freely|
|Sham exposure||A sham exposure was conducted.|
The latencies of all visual evoked potential components in all exposure groups (groups 1-3) were significantly prolonged compared to the control group. No differences in amplitudes were found between the groups.
For somatosensory evoked potentials, all potential components of group 3 (prenatal and postnatal exposure), 3 components of group 2 (postnatal exposure) and 2 components of group 1 (prenatal exposure) were significantly delayed compared to the control group. Moreover, group 3 showed significantly increased amplitude peak-to-peak values of potential components compared to the control group.
Lipid peroxidation in the brain was significantly increased in groups 1 and 2 compared to the control group. In the retina, lipid peroxidation was significantly increased in all exposure groups compared to the control group.
No differences in general health and body weight were found between animals of all groups.
The authors conclude that prenatal and/or postnatal exposure of rats to a 50 Hz electric field might influence evoked potentials. Lipid peroxidation in the brain and retina might be associated with this effect.