Short-term water deprivation does not increase blood pressure variability or impair neurovascular function in healthy young adults

Research output: Contribution to journalArticle

Authors

External Institution(s)

  • University of Delaware

Details

Original languageEnglish (US)
Pages (from-to)R112-R121
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume318
Issue number1
StatusPublished - Jan 2020
Peer-reviewedYes

Abstract

High dietary salt increases arterial blood pressure variability (BPV) in salt-resistant, normotensive rodents and is thought to result from elevated plasma [Na+] sensitizing central sympathetic networks. Our purpose was to test the hypothesis that water deprivation (WD)-induced elevations in serum [Na] augment BPV via changes in baroreflex function and sympathetic vascular transduction in humans. In a randomized crossover fashion, 35 adults [17 female/18 male, age: 25 + 4 yr, systolic/diastolic blood pressure (BP): 107 + 11/60 + 7 mmHg, body mass index: 23 + 3 kg/m2] completed two hydration protocols: a euhydration control condition (CON) and a stepwise reduction in water intake over 3 days, concluding with 16 h of WD. We assessed blood and urine electrolyte concentrations and osmolality, resting muscle sympathetic nerve activity (MSNA; peroneal microneurography; 18 paired recordings), beat-to-beat BP (photoplethysmography), common femoral artery blood flow (Doppler ultrasound), and heart rate (single-lead ECG). A subset of participants (n = 25) underwent ambulatory BP monitoring during day 3 of each protocol. We calculated average real variability as an index of BPV. WD increased serum [Na+] (141.0 + 2.3 vs. 142.1 + 1.7 mmol/L, P < 0.01) and plasma osmolality (288 + 4 vs. 292 + 5 mosmol/kg H2O, P < 0.01). However, WD did not increase beat-to-beat (1.9 + 0.4 vs. 1.8 + 0.4 mmHg, P = 0.24) or ambulatory daytime (9.6 + 2.1 vs. 9.4 + 3.3 mmHg, P = 0.76) systolic BPV. Additionally, sympathetic baroreflex sensitivity (P = 0.20) and sympathetic vascular transduction were not different after WD (P = 0.17 for peak mean BP following spontaneous MSNA bursts). These findings suggest that, despite modestly increasing serum [Na+], WD does not affect BPV, arterial baroreflex function, or sympathetic vascular transduction in healthy young adults.

    Research areas

  • Arterial baroreflex function, Blood pressure variability, Hypohydration, Serum sodium concentrations, Sympathetic vascular transduction

Citation formats

APA

Watso, J. C., Robinson, A. T., Babcock, M. C., Migdal, K. U., Wenner, M. M., Stocker, S. D., & Farquhar, W. B. (2020). Short-term water deprivation does not increase blood pressure variability or impair neurovascular function in healthy young adults. American Journal of Physiology - Regulatory Integrative and Comparative Physiology, 318(1), R112-R121. https://doi.org/10.1152/AJPREGU.00149.2019

Harvard

Watso, JC, Robinson, AT, Babcock, MC, Migdal, KU, Wenner, MM, Stocker, SD & Farquhar, WB 2020, 'Short-term water deprivation does not increase blood pressure variability or impair neurovascular function in healthy young adults', American Journal of Physiology - Regulatory Integrative and Comparative Physiology, vol. 318, no. 1, pp. R112-R121. https://doi.org/10.1152/AJPREGU.00149.2019