Abstract: SA-PO346
High Dietary Sodium Increases Urinary Endothelin-1 Excretion in Salt-Resistant Women but Not in Men
Session Information
- Hypertension, CVD, and the Kidneys: Clinical Research
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Hypertension and CVD
- 1602 Hypertension and CVD: Clinical
Authors
- Fetter, Rebecca Caroline, Vanderbilt Department of Medicine, Nashville, Tennessee, United States
- Benjamin, Jazmine I., Vanderbilt Department of Medicine, Nashville, Tennessee, United States
- Nasci, Victoria L., Vanderbilt Department of Medicine, Nashville, Tennessee, United States
- Stock, Joseph M., Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, United States
- Romberger, Nathan T., Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, United States
- Watso, Joseph, Indiana University Bloomington Department of Kinesiology, Bloomington, Indiana, United States
- Babcock, Matthew C., Cardiovascular and Applied Physiology Laboratory, Florida State University, Tallahassee, Florida, United States
- Wenner, Megan, Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, United States
- Robinson, Austin, Division of Geriatric Medicine, University of Colorado Denver, Aurora, Colorado, United States
- Gohar, Eman Y., Vanderbilt Department of Medicine, Nashville, Tennessee, United States
Background
Endothelin-1 (ET-1) is a peptide thought to be implicated in gender differences in hypertension (HTN). In the kidney, ET-1 promotes natriuresis, and urinary ET-1 excretion reflects renal ET-1 production. Prior studies in our laboratory demonstrated that female rats exhibited higher urinary ET-1 than males on a normal salt diet. When switched to a high salt diet, only the male rats exhibited increased urinary ET-1. However, potential gender differences in the effect of dietary sodium on the renal ET-1 system in humans are unclear. Thus, we aimed to test the hypothesis that women would have higher overall ET-1 excretion than men and that increasing dietary sodium would augment ET-1 excretion only in men.
Methods
Salt-resistant participants (7 women; 14 men) with a baseline blood pressure (BP) of less than 140/90 mmHg followed recommended sodium (RS; 2300 mg/day) and high sodium (HS; 7000 mg/day) diets for 10 days, administered in random order with a washout of at least 4 weeks between interventions. At the end of each diet, 24-hour ambulatory BP was measured and 24-hour urine collected. ET-1 excretion was quantified using the QuantiGlo (R&D) ET-1 ELISA. ET-1 excretion on the RS and HS diets in men and women was evaluated using a repeated measures two-way ANOVA with post hoc Sidak’s test.
Results
Systolic, mean, and diastolic BP were not different between the RS and HS diets in either gender. Women exhibited higher urinary ET-1 than men, which was most evident on the HS diet (P=.0228). Only women experienced a significant increase in ET-1 excretion on the HS diet (196.01±18.40 pg/day) as compared to the RS diet (127.24±19.52 pg/day) (P=.0096). There was no significant gender difference or diet difference in urine flow rate (UFR).
Conclusion
Women exhibited higher urinary ET-1 excretion than men. Only women had significantly increased urinary ET-1 during the HS versus the RS diet, which opposes our hypothesis. Understanding gender differences in ET-1-mediated sodium regulation could potentially inform future studies toward developing gender-specific therapeutics for HTN.
Funding
- NIDDK Support