The latency of baroreflex cardiac and vascular resistance response in addition to baroreflex sensitivity index contribute to the stability of arterial blood pressure control. The objective of our study was to examine the effect of 3-month moderate exercise training on carotid - cardiac and carotid-vascular resistance response in 20 mild hypertensive young men (HTS), (23 0.9 years) and matched 20 normotensive men (NTS), (23 0.5 years) We recorded continously: arterial blood pressure (BP) by Finapres method, heart rate by ECG, stroke volume and arm blood flow by impedance reography. Carotid baroreceptors were stimulated by applying negative pressure bilaterally on the carotid areas in the neck in 10 mmHg steps from -10 to -60 mmHg. The latencies of the response were measured from onset of neck suction to the maximal R-R interval or to the minimal value of total peripheral resistance during the suction time. 3-month moderate exercise training increased signifcantly the carotid - cardiac responsiveness in both groups. After training in hypertensive subjects we observed significant shortening: of carotid baroreflex vascular resistance latency by 202 percent and of carotid - cardiac latency by 18 3 percent. In trained normotensives the shortening of carotid-cardiac latency was significant. The percentage decrease in carotid-vascular resistance latency after training was greater in hypertensive subjects.We conclude that decrease of carotid -vascular resistance and carotid - cardiac latency augments the effectiveness and stability of inhibitory baroreflex in mild hypertensive trained man.

The study was supported by KBN Grant 4P05D6018