Does pulsatile and sustained neck pressure or neck suction produce differential cardiovascular and sympathetic responses in humans?

Shigehiko Ogoh, Paul J. Fadel, Janelle M. Hardisty, Wendy L. Wasmund, David M. Keller, Peter B. Raven, Michael S. Smith

Research output: Contribution to journalArticle

16 Scopus citations

Abstract

Although square-wave sustained and R wave-triggered pulsatile stimuli have been used to assess carotid baroreflex (CBR) function in humans, it remains unclear whether these different stimulus protocols elicit comparable responses and whether CBR responses adapt during prolonged stimulation. Thus, we measured muscle sympathetic nerve activity (MSNA), heart rate (HR) and mean arterial pressure (MAP) in response to +30 Torr neck pressure (NP) and -30 Torr neck suction (NS) delivered for 20 s either as a sustained or pulsatile stimulus. CBR-mediated changes in MSNA, HR and MAP were similar with sustained and pulsatile stimuli. The time course of MSNA and HR responses identified that significant changes occurred during the initial 5 s and were better maintained over 20 s with NP than with NS. Changes in MAP exhibited a slower onset with the peak increase during NP occurring at 10 s (sustained, 7 ± 1 mmHg; pulsatile, 7 ± 1 mmHg; P > 0.05 and the nadir during NS occurring at 20 s (sustained, -7 ± 1 mmHg; pulsatile, -9 ± 2 mmHg, P > 0.05). These data demonstrate that sustained and pulsatile NP and NS produce comparable CBR-mediated responses. Furthermore, despite MSNA and HR returning towards baseline during NS, CBR-mediated changes in MAP are well maintained over 20 s of NS and NP.

Original languageEnglish
Pages (from-to)595-601
Number of pages7
JournalExperimental physiology
Volume88
Issue number5
DOIs
StatePublished - Sep 2003

Fingerprint Dive into the research topics of 'Does pulsatile and sustained neck pressure or neck suction produce differential cardiovascular and sympathetic responses in humans?'. Together they form a unique fingerprint.

  • Cite this