Vascular and cardiac effects of stress in albino rats of different sex and age groups.

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.

Effect of age and sex on blood pressure, development of renal hypertension, and concentration of nitric oxide in the blood of albino rats.

The mean blood pressure did not depend on the sex of animals and was characterized by the same ontogenetic changes in males and females. The mean blood pressure in infantile and, particularly, in old rats was higher than in adult animals. The increase in blood pressure in old rats was accompanied by a decrease in NO production.

Sex-specific peculiarities of cholinergic regulation of the cardiovascular system in normal and hypertensive rats.

Cardiovascular sensitivity to atropine and acetylcholine is reduced in renal hypertension. Hypertension in females is more benign and the hypotensive effects of acetylcholine in them are less attenuated than in males. Cardiovascular sensitivity to cholinergic effects in females is higher in health and hypertension, which improves their resistance to cardiovascular pathology.

Sex-related differences in cardiovascular stress reactivity in healthy and hypertensive rats.

In healthy females the chronotropic effects of stress are more pronounced, while the hypertensive effects are weakened compared to males. Hemodynamic parameters in females returned to normal more rapidly than in males. Renovascular hypertension in males is more pronounced than in females and is associated with increased cardiovascular stress reactivity (in females it is associated with decreased cardiovascular stress reactivity), which increase the risk of cardiovascular complications in males.

Sex-related differences in nitric oxide content in healthy and hypertensive rats at rest and under stress conditions.

Immobilization was followed by an increase in blood NO concentration in male and female rats. After renovascular hypertension modeling blood pressure was higher and the decrease in nitric oxide concentration was more pronounced in males than in females. The levels of nitric oxide in healthy and hypertensive females at rest and during stress were higher than in males.