Coincidental relationship of activity in the sympathetic ganglioglomerular nerve innervating the carotid bifurcation with the intracarotid systolic pulses.
The innervation of the carotid bifurcation by the ganglioglomerular nerve originating from the superior cervical ganglion has brought about the idea that the baroreceptor function is under efferent control. Provided that the efferent activity coincides with the systolic pulse, the receptor elements may be influenced at this critical moment. Therefore, the coincidental relationship was investigated between the efferent sympathetic bursts of the ganglioglomerular nerve and the intracarotid systolic pressure rise. It was found that the bursts appear regularly before pressure rises and continue for the ensuing 160-220 msec. The bursts onset varied greatly depending on the R-R interval. On the contrary, the burst cessation occurred with a constant delay following systolic pressure rise. The single burst duration was found to be modulated by the rhythm of respiration and altered by hemorrhage, but the coincidence remained consistent. It is, therefore, concluded that the temporal prerequisite exists which enables the baroreceptor to be influenced by sympathetic control just at the moment when systolic pulse affects the carotid baroreceptor.
D000818:Animals; D001794:Blood Pressure; D002339:Carotid Arteries / Q000294:innervation* / Q000502:physiology; D004285:Dogs; D004525:Efferent Pathways / Q000502:physiology; D004553:Electric Conductivity; D005260:Female; D005727:Ganglia, Spinal / Q000502:physiology*; D006339:Heart Rate; D008297:Male; D012119:Respiration