A juvenile social recognition paradigm was used and memory retention was tested at 30 and 300 min after an adult was exposed to a juvenile (used as social stimuli).
To test the influence of estrogens on cognition, 40 of 80 adult rats were ovariectomized. Three days before the tests 16 of these rats received a daily injection of 17-b estradiol.
|Setup||Coils were spaced apart at a distance of equal radii in upper and lower face of the plastic exposure chamber (30 x 30 x 15 cm) and provided uniform field distribution. Sham exposed animals were kept in the same chamber for the same amount of time but with the coils switched off.|
|magnetic flux density||1 mT||unspecified||measured||-||-|
It was shown that an intact social recognition memory was present at 30 min in both gonadally intact and ovariectomized rats with or without extremely low frequency electromagnetic field. However, whereas gonadally intact control rats failed to show retention of the recognition memory at 300 min, those additionally exposed to extremely low frequency electromagnetic field did. This shows that the enhanced duration effect of extremely low frequency electromagnetic fields on social recognition memory occurs in gonadally intact females as well as in males (see publication 11223).
In addition, the data revealed that the exposure facilitation of memory retention was prevented by ovariectomy but restored by exogenous treatment with estrogen. This suggests that this extremely low frequency electromagnetic field effect on social recognition memory is estrogen-dependent.