DAILY EXERCISE IMPROVED BLOOD-PRESSURE HOMEOSTASIS OF RATS SUBJECTED TO SURGICAL STRESS

The effect of daily spontaneous running on blood pressure homeostasis (BPH) was evaluated in 19 male and 13 female control rats and 7 male a nd 13 female daily spontaneous running rats subjected to surgery and s ubsequent repetitive hemodynamic disturbances. BPH was operationally d efined as the ability to maintain mean arterial pressure above 60 mmHg during the experimental protocol. The length of time the rats maintai ned BPH was compared across males and females and trained and control groups. Significant sex (P = 0.01) and training (P = 0.05) effects wer e found. Females maintained ho meostasis longer than males and trained longer than controls. Sex effects were not due to differences in the body mass. The mechanisms responsible for the higher resistance to det erioration of homeostasis merit further investigation.