[Reaction of the endocrine system and peripheral blood of rats to a single and chronic exposure to pulsed low-frequency electromagnetic field].

Wistar male rats underwent a single exposure for 20 min, 1 and 2.5 hour to a pulsed electromagnetic field of 20 mT or a single exposure for 2.5 hour and a chronic exposure for 6 hours a day during 30 days to a pulsed electromagnetic field of 0.1 mT, the pulse time and an interval between pulses being 10(-2) sec. As a result, the experimental animals showed changes in the activity of the adrenals, thyroid and sex glands as well as eosinopenia and lymphopenia. The concentration of thyroid hormones and lymphocytes remained lowered during 2 months after a single exposure to 20 mT. In some cases the exposure modified the physiological responses of rats to an acute stress-5-hour immobilization.