[Sex differences in the dynamic response reactions to emotional stress exposures in white rats]

The changes of adrenal and plasma corticosterone and adrenal catecholamines were studied in male and female rats during and after short-term (10 min) emotional stress (the sight and squeals of immobilised partners) and emotional-pain stress (immobilisation). Obvious sexual differences in the stress reactions were revealed: females developed the greatest increase in corticosterone levels which returned to initial values within 40-60 min after cessation of the stress. Concentrations of adrenaline decreased in the first 5 min of stress and became normal by the 10th min. Males developed the greatest increase in the corticosterone levels not during stress but 20-40 min after termination of the stressful stimulus. The adrenaline level increased by the 10th min of stress and became normal within 20 min of poststress period. The advantage of "female's" strategy in stress reactions is discussed.