Rats were exposed in vivo, and possible endocrine changes were investigated by determination of several endocrine hormones in blood samples. Investigations were carried out concerning the hormones thyroxine (T4), triiodothyronine (T3), and corticosterone. T4 and T3 are formed and secreted by the thyroid gland, whereas corticosterone is a adrenal cortex product.
|Exposure duration||continuous for 8 h|
|Distance between exposed object and exposure source||1.55 m|
|Exposure room||chamber 2,5 m x 3,0 m x 2,5 m lined with HPY-18 microwave absorber( -45dB)|
|Setup||animals placed in 2.5 cm thick Styrofoam cages (10 cm x 20 cm) positioned inside the chamber|
|Sham exposure||A sham exposure was conducted.|
The microwave exposure had no effects on the serum concentrations of thyroxine (T4), triiodothyronine (T3) and the uptake of T3. These unaltered hormone concentrations could be interpreted in that way that the thyroid gland was not affected by exposure. The serum concentrations of corticosterone, which is adrenal cortex made, were nonuniform. Low level exposure leads to increased concentration, whereas at high level exposure the corticosterone concentration was similar to the unexposed controles.
These results suggest that the experimental procedure effects the adrenal cortex, and that this effect could be counteracted by high level exposure.