Studies on Acute in Vivo Exposure of Rats to 2450-MHz Microwave Radiation: II. Effects on Thyroid and Adrenal Axes Hormones

• Published in: Radiation research 1981-12, Vol.88 (3), p.448-455
• Main Authors: Abhold, Raymond H., Ortner, Mary J., Galvin, Michael J., McRee, Donald I.
• Format: Article
• Language: English
• Subjects: Animals; Corticosterone; Corticosterone - blood; Density; Electric fields; Exposure chambers; Hormones; Hypothalamo-Hypophyseal System - radiation effects; Irradiation; Male; Microwaves; Pituitary-Adrenal System - radiation effects; Plasma density; Radiation Dosage; Rats; Standard error; Thyroid Gland - radiation effects; Thyroxine - blood; Time Factors; Triiodothyronine - blood
• ISSN: 0033-7587; 1938-5404
• DOI: 10.2307/3575634

The effects of 8 hr continuous exposure of rats to 2450-MHz (cw) microwave radiation were studied at incident power densities of 0, 2, and 10 mW/ cm2. Thyroid axis function, as measured by serum thyroxine ( T4) and triiodothyronine ( T3) as well as T3 uptake, free thyroxine index, and $\text{adjusted-}{\rm T}_{4}$ values was not altered by the experimental conditions. Adrenal axis activity was also unaffected in rats exposed to $2\ {\rm mW}/{\rm cm}^{2}$ microwave radiation for 8 hr. In the 10 mW/ cm2 group, the serum corticosterone levels were less than in the 0 or $2\ {\rm mW}/{\rm cm}^{2}$ groups (7.8 versus 9.9 μg/dl). The experimental protocol increased serum corticosterone levels (7.0 versus 9.9 μg/dl for the nonhandled and sham-exposed groups, respectively); however, the corticosterone concentration in the 10 mW/ cm2 group was similar to that in the untreated (nonhandled) controls (7.8 versus 7.0 μg/dl). This modified adrenal axis function gives further support to the concept that microwave radiation affects endocrine function.