title: Baroreflex sensitivity is higher during acute psychological stress in healthy subjects under β-adrenergic blockade.
abstract: Acute psychological stress challenges the cardiovascular system with an increase in BP (blood pressure), HR (heart rate) and reduced BRS (baroreflex sensitivity). β-adrenergic blockade enhances BRS during rest, but its effect on BRS during acute psychological stress is unknown. This study tested the hypothesis that BRS is higher during acute psychological stress in healthy subjects under β-adrenergic blockade. Twenty healthy novice male bungee jumpers were randomized and studied with (PROP, n=10) or without (CTRL, n=10) propranolol. BP and HR responses and BRS [cross-correlation time-domain (BRSTD) and cross-spectral frequency-domain (BRSFD) analysis] were evaluated from 30 min prior up to 2 h after the jump. HR, cardiac output and pulse pressure were lower in the PROP group throughout the study. Prior to the bungee jump, BRS was higher in the PROP group compared with the CTRL group [BRSTD: 28 (24-42) compared with 17 (16-28) ms·mmHg-1, P<0.05; BRSFD: 27 (20-34) compared with 14 (9-19) ms·mmHg-1, P<0.05; values are medians (interquartile range)]. BP declined after the jump in both groups, and post-jump BRS did not differ between the groups. In conclusion, during acute psychological stress, BRS is higher in healthy subjects treated with non-selective β-adrenergic blockade with significantly lower HR but comparable BP.
authors.affiliation: Department of Internal Medicine, Academic Medical Center, University of Amsterdam, The Netherlands.
authors.forename: Jasper
authors.initials: J
authors.lastname: Truijen
authors.forename: Shyrin C A T
authors.initials: SC
authors.lastname: Davis
authors.forename: Wim J
authors.initials: WJ
authors.lastname: Stok
authors.forename: Yu-Sok
authors.initials: YS
authors.lastname: Kim
authors.forename: David J
authors.initials: DJ
authors.lastname: van Westerloo
authors.forename: Marcel
authors.initials: M
authors.lastname: Levi
authors.forename: Tom
authors.initials: T
authors.lastname: van der Poll
authors.forename: Berend E
authors.initials: BE
authors.lastname: Westerhof
authors.forename: John M
authors.initials: JM
authors.lastname: Karemaker
authors.forename: Johannes J
authors.initials: JJ
authors.lastname: van Lieshout
mesh_terms: D000208:Acute Disease; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000328:Adult; D017704:Baroreflex / Q000187:drug effects* / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D011433:Propranolol / Q000494:pharmacology; D013315:Stress, Psychological / Q000503:physiopathology*; D055815:Young Adult
chemical_list: D000319:Adrenergic beta-Antagonists; D011433:Propranolol