[Effects of whole-body microwave exposure on the plasma corticosterone, glucose, uric acid and allantoin levels in rats].

To investigate the effects of whole-body microwave exposure on plasma corticosterone, glucose, uric acid and allantoin levels, rats weighing 245-300 g (light group) and 440-510 g (heavy group) were exposed to microwaves with a frequency of 2,450 MHz at the power density of 10 mW/cm2 under an ambient temperature of 21 to 23 degrees C for one hour. Rectal temperatures were increased by 3.4 degrees C in the light group and 1.4 degrees C in the heavy group after microwave exposure. Plasma levels of corticosterone, glucose and uric acid did not change in both groups after microwave exposure. Plasma levels of allantoin increased significantly only in the heavy group after microwave exposure. These results suggest that the plasma levels of allantoin, a metabolite of uric acid, may be useful as a biological variable for assessment of the effects of whole-body microwave exposure in rats. The increase of plasma allantoin level after microwave exposure could not be explained only by the degree of increased rectal temperature caused by hyperthermic effects of microwaves.