8.8 SYMPATHETIC VASOCONSTRICTOR RESPONSE TO LOWER BODY NEGATIVE PRESSURE IN YOUNG OBESE ADULTS: THE PRELIMINARY FINDING

DOI

10.1016/j.artres.2016.10.064How to use a DOI?

Abstract

Background: Elevations in muscle sympathetic nerve activity (MSNA) and sympathetic vasoconstrictor responsiveness to sympathoexcitation are associated with increased cardiovascular risks, which affect hemodynamics, and have been reported in obese adults with metabolic syndrome (1–3). It remains unclear whether this observation may also be present in young metabolically healthy obese adults.

Purpose: To compare sympathetic vasoconstrictor and hemodynamic responsiveness to lower body negative pressure (LBNP, −20 mmHg) in young normal-weight (NW) vs. obese (OB) adults.

Method: Eleven NW (female=6; 25±2 yrs; 22.4±0.6 kg/m2) and 13 OB adults (female=6; 27±1 yrs; 32.7±0.6 kg/m2) underwent 2-min of LBNP in the supine position. Ultrasonography [brachial diameter, forearm blood flow (FBF), forearm vascular conductance (FVC)], MSNA [burst frequency, total MSNA, sympathetic vascular transduction], and beat-to-beat hemodynamics [heart rate (HR), mean arterial pressure (MAP), total peripheral resistance (TPR), cardiac output (CO), stroke volume (SV), systemic compliance (SC)] were reported. FBF and FVC were normalized to lean forearm mass, and TPR, CO, SV, and SC to body surface area.

Results: Baseline MAP was lower in OB (P<0.05). In response to LBNP, normalized FBF, FVC, SV, CO, and SC decreased whereas TPR increased similarly in both groups (P<0.05). Brachial diameter and HR did not change in both groups. MAP decreased similarly by ∼2–4 mmHg, but the values were lower in the OB group (P<0.05). Burst frequency, total MSNA, and sympathetic vascular transduction increased similarly in both groups (P<0.05).

Conclusion: Young metabolically healthy obese adults did not exhibit altered sympathetic vasoconstrictor responsiveness under resting condition.

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TY  - JOUR
AU  - Kanokwan Bunsawat
AU  - Georgios Grigoriadis
AU  - Bo Fernhall
AU  - Tracy Baynard
PY  - 2016
DA  - 2016/11/24
TI  - 8.8 SYMPATHETIC VASOCONSTRICTOR RESPONSE TO LOWER BODY NEGATIVE PRESSURE IN YOUNG OBESE ADULTS: THE PRELIMINARY FINDING
JO  - Artery Research
SP  - 67
EP  - 67
VL  - 16
IS  - C
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2016.10.064
DO  - 10.1016/j.artres.2016.10.064
ID  - Bunsawat2016
ER  -