Fig. 1

The influence of sequential baroafferent denervation on the baroreflex bradycardia and sympathoinhibition evoked by the phenylephrine-induced pressor response. a Sequential denervation of the aortic nerves followed by denervation of the carotid sinus nerves (AoN–CSN) in one rat. b Sequential denervation of the carotid sinus nerves followed by denervation of the aortic nerves (CSN–AoN) in another rat. ‘Intact’, 1st, 2nd, 3rd, and ‘all’ mean that the number of the denervated baroafferent nerves was zero, one, two, three, and four, respectively. ‘Averaged RSNA’ shows moving averages of the integrated RSNA. The baroreflex bradycardia was obviously blunted by single denervation of the aortic nerve irrespective of the AoN–CSN or CSN–AoN group, whereas the baroreflex inhibition of RSNA was well preserved as long as a single aortic or carotid sinus nerve remained intact. Arrhythmia was sometimes observed in the intact and 3rd condition of the CSN–AoN. HR heart rate, AP arterial blood pressure, RSNA renal sympathetic nerve activity