Vascular and Cardiac Effects of Stress in Albino Rats of Different Sex and Age Groups

Abstract

Stress exposure induced similar cardiac effects in male and female infantile rats, but vascular reactions to stress in males were more pronounced than in females. In mature male rats (but not in females), both cardiac and vascular responses to stress decreased in comparison with infantile animals. In adult rats, cardiac effects of stress were more pronounced than the vascular response; females demonstrated greater cardiac response and less significant vascular reactions than males. Aging was accompanied by a decrease in the cardiac response and increase in the vascular reaction to stress. These changes were more significant in females than in males. In contrast to infantile and adult animals, old females demonstrated greater vascular response to stress than male rats. The observed sex-dependent changes in the ontogeny of vascular and cardiac response to stress are discussed in light of sex- and age-related peculiarities of hypertension development.