Effect of adaptation to not damaging stress influences on resistance to acute stress in rats August line and Wistar population

Abstract

There were compared the effects of stress adaptation of August and Wistar rats on their tolerance to acute stress exposure. The role of stress-system (catecholamines maintenance in blood) and stress-limiting systems: blood NO-systems (the rate of stable NO metabolites nitrates/nitrites in blood), and serotonin system in stomach (the rate of 5-hydroxytriptamine – 5-OT). It was shown that the rats initially more tolerant to acute stress (August rats) can poorly adapt to recurrent stress exposures, and their stomach stress-tolerance is reduced as compared with the control. The Wistar rats with lower initial stress tolerance can more vigorously resist the recurrent stress exposures and they were tolerant to stress stomach damages, as compared to the control. It was also shown that these changes were due to the effects of adaptation on the activation of the stress-limiting systems: the stress-adaptation reduced the activity of the stress-limiting systems in August rats and enhanced them in the Wistar rats.