Sympathetic activation decreases medium-sized arterial compliance in humans

A noninvasive method, which combines the new high-resolution echo-tracking system for determining systolic/diastolic arterial diameter changes and the Finapres system for measuring instantaneous systolic/ diastolic pressure-diameter in human heart, indicates that sympathetic activation reduces radial arterial compliance in the human heart. Mental stress and cold pressor tests during sympathetic activation increase the mean arterial pressure and pulse pressure and decrease the stroke change in diameter, while radial arterial mean diameter remains constant. The variations in radial arterial smooth muscle tone and those in distending blood pressure interact to mediate the decrease in arterial compliance.