Differences between August and Wistar rats in stress reactions and in the development of adaptation to stress

Abstract

Control and acutely stressed August rats have corticosterone levels 62% and 15% higher, respectively, than their Wistar counterparts, indicating that the activity of stress-mediating hypothalamic-pituitary-adrenal system in August rats is higher. On the other hand, the intensity of stress reactions and, consequently, the degree of activation of this system in August rats are 40–50% lower, as is the blood level of creatine phosphokinase. During adaptation to stress, August and Wistar rats show a similar decrease in the stress reaction and in its damaging effects. However, judging from the blood corticosterone/insulin ratio, adaptation to stress in August rats coincides with intensification of catabolic processes and a reduction in the efficiency of energy production.