Premium
Central hemodynamic responses to an acute sodium load in black and white subjects.
Author(s) -
Delaney Erin Paul,
Wenner Megan M,
Prettyman Allen V,
Stillabower Michael E,
Farquhar William B
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.4.a737-a
Subject(s) - hemodynamics , white (mutation) , cardiology , medicine , chemistry , biochemistry , gene
Chronically high dietary sodium intake has been associated with elevated blood pressure (BP). Studies have shown that black adults demonstrate a higher degree of sodium sensitivity than white adults. PURPOSE To examine the acute effects of sodium on BP, cardiac output (Qc), and peripheral vascular resistance (PVR) in black and white subjects. We hypothesized that a hypertonic saline infusion (3% NaCl; HSI) would increase BP more in black subjects. METHODS 19 black (age: 22.9 ± 1.4 yrs) and 16 white (age: 25.9 ± 1.5 yrs) healthy subjects underwent a 60‐minute HSI. BP (Finometer), Qc (CO 2 rebreathing), serum sodium, and osmolality were assessed throughout the HSI. PVR was calculated. Results are reported as mean ± standard error and a two way repeated measures ANOVA was used to compare the effects of time and race. RESULTS During the HSI there was an increase in serum sodium (135.3 ± 0.4 to 141.1 ± 0.4 mmol/L) and osmolality (287.4 ± 0.7 to 296.6 ± 0.7) that was not different between the races. While the increase in mean BP was not different between the races (black: 10.1 mmHg vs. white: 9.5 mmHg, p = 0.795), the time course for the change in Qc (and hence, PVR) was different (ANOVA race, p < 0.05). CONCLUSION Preliminary analysis suggests that the HSI increased BP in all subjects, but the mechanisms underlying the change in BP were different black and white subjects. Supported by NIH grant RI5 HL074851‐01.