Beat-to-Beat Regulation of Heart Rate by Afferent Stimulation of the Aortic Nerve.

摘要

Repeated electrical stimulation of the aortic nerve, when confined to one cardiac cycle, caused heart rate reduction in the anesthetized rabbit. The average fall in heart rate due to supramaximal stimulation was 8.4 + or - 0.3 beats/min (+ or - SEM). Extent of bradycardia was more closely related to total number of impulses within the stimulus burst than to either burst duration or impulse frequency. The latency to onset of the response could not be altered by changes in any of the stimulus parameters, nor could it be related to the position of the stimulus burst within the cardiac cycle. These results indicate that beat-to-beat regulation of heart rate can be accomplished when afferent aortic nerve activity is altered. (Author)