Abstract
Introduction: Premenopausal women are protected from cardiovascular disease compared to age-matched men. Estrogen (E2) plays important roles in these protective mechanisms.
Purpose: Our goal was to determine if E2 reduces angiotensin II (AngII)-induced elevation in blood pressure in ovariectomized (OVX) mice. We also hypothesized that E2 affects renal excretion of water and sodium.
Methods: Four-week-old CD-1 OVX mice were placed in metabolic cages for a five-day baseline period followed by implantation of an Alzet osmotic pump containing either vehicle or AngII (1µg/kg/min) and either a placebo or 0.7mg E2 pellet. Measurements of water intake (WI, ml/day), urine volume (UV, ml/day), and urine sodium excretion (UNaE, µEq/day) were recorded daily in the baseline and ten-day post-implantation periods in three groups of mice: vehicle-placebo (V-P), AngII-placebo (AngII-P), and AngII-E2 (n=4/group). Systolic blood pressure (SBP, mmHg) was determined via the tail-cuff technique.
Results: Delta SBP (baseline vs AngII period) was higher in AngII-P but not significantly different from AngII-E2 mice, (33.1±3.5 vs 24.5±4.0, respectively). AngII-E2 mice compared to AngII-P mice had lower WI (4.2±0.02 vs 6.9±0.05, respectively, p<0.001), lower UV (1.3±0.02 vs 2.6±0.03, respectively, p<0.03), and lower UNaE (110.5±20.7 vs 199.7±10.8, respectively, p<0.003).
Conclusion: E2 administration reduces WI, UV, and UNaE during a ten-day AngII-infusion in OVX mice. E2 did not significantly reduce SBP. Studies of longer duration are underway to investigate the important E2-induced mechanisms on blood pressure regulation.
Purpose: Our goal was to determine if E2 reduces angiotensin II (AngII)-induced elevation in blood pressure in ovariectomized (OVX) mice. We also hypothesized that E2 affects renal excretion of water and sodium.
Methods: Four-week-old CD-1 OVX mice were placed in metabolic cages for a five-day baseline period followed by implantation of an Alzet osmotic pump containing either vehicle or AngII (1µg/kg/min) and either a placebo or 0.7mg E2 pellet. Measurements of water intake (WI, ml/day), urine volume (UV, ml/day), and urine sodium excretion (UNaE, µEq/day) were recorded daily in the baseline and ten-day post-implantation periods in three groups of mice: vehicle-placebo (V-P), AngII-placebo (AngII-P), and AngII-E2 (n=4/group). Systolic blood pressure (SBP, mmHg) was determined via the tail-cuff technique.
Results: Delta SBP (baseline vs AngII period) was higher in AngII-P but not significantly different from AngII-E2 mice, (33.1±3.5 vs 24.5±4.0, respectively). AngII-E2 mice compared to AngII-P mice had lower WI (4.2±0.02 vs 6.9±0.05, respectively, p<0.001), lower UV (1.3±0.02 vs 2.6±0.03, respectively, p<0.03), and lower UNaE (110.5±20.7 vs 199.7±10.8, respectively, p<0.003).
Conclusion: E2 administration reduces WI, UV, and UNaE during a ten-day AngII-infusion in OVX mice. E2 did not significantly reduce SBP. Studies of longer duration are underway to investigate the important E2-induced mechanisms on blood pressure regulation.
| Original language | American English |
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| State | Published - 22 Aug 2020 |
| Event | Oklahoma State University Center for Health Sciences Research Day 2019 - Oklahoma State University Center for Health Sciences, TULSA, United States Duration: 21 Feb 2019 → 22 Feb 2019 https://openresearch.okstate.edu/handle/20.500.14446/323834 (Open Research Oklahoma - OSU Center for Health Sciences - Research Day 2019) |
Conference
| Conference | Oklahoma State University Center for Health Sciences Research Day 2019 |
|---|---|
| Abbreviated title | Research Day 2019 |
| Country/Territory | United States |
| City | TULSA |
| Period | 21/02/19 → 22/02/19 |
| Internet address |
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