[Steroid hormone dynamics in cold adaptation of rats of different inbred strains]

In experiments on WAG, Sprague-Dawley and August rats the significance of genetic differences in the adrenocortical and gonadal response to long-term cold adaptation was demonstrated. The highest blood corticosterone level in WAG rats and the lowest one in August rats were seen following the 4-week exposure to 10 degrees C. A decreased blood testosterone concentration under cold conditions was observed only in August rats. Aldosterone excretion with the urine diminished during the cold exposure in WAG and Sprague-Dawley rats, being enhanced in August rats. The relationship is discussed between hormonal and metabolic changes under prolonged exposure to cold.