P0151SEXUAL DIMORPHISM IN HYPERTENSION ACCORDING TO THE CHANGE OF URINE SODIUM AND VOLUME EXCRETION BY SEX OR MENOPAUSE

Abstract Background and Aims A recent study demonstrated female rats more rapidly excreted urine sodium and water under saline bolus infusion than male rats, and suggested sexual dimorphisms in renal transporters. However, the sexual differences in renal salt and water excretion was not yet investigated with human data. We purposed to clarify whether the sexual difference of natriuretic and diuretic ability exists, and it contributes to decreasing blood pressure (BP) in nondiabetic chronic kidney disease (CKD) patients. Method This is a secondary analysis of an open-label, randomized, controlled study determining the effect of intensive low-salt diet education on BP and albuminuria in nondiabetic CKD patients. A total of 235 patients had stopped all renin-angiotensin blocking agents or diuretics during a run-in period for eight weeks (0w). After the run-in period, they received olmesartan (40mg daily) for eight weeks (8w), and then maintained the same medicine with low-salt diet education for an additional eight weeks (16w). Results Mean age of premenopausal women (n=50), same-aged young men (n=76), postmenopausal women (n=68), and same-aged older men (n=41) was 40.7, 40.2, 59.0, and 69.9 years old, respectively. Their MDRD eGFR was 76.2, 71.6, 59.8, and 58.8 mL/min/1.73m2, respectively. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) was lower in premenopausal women (129/79 mmHg) than in young men (134/83 mmHg). Daily salt intake decreased in 16w in premenopausal women (1839 → 1288mg, p=0.008) and young men (2494 → 1552mg, p=0.001) compared with them in 0w, while there was no significant change in postmenopausal women (2443 → 2171mg, p=0.610) and older men (2870 → 2366mg, p=0.458). Except for the premenopausal women (136 (0w) → 133 (16w) mEq/day, p=0.749), urine sodium excretion for 24 hours significantly decreased in 16w compared with that in 0w or 8w (young men: 154 (8w) → 137 (16w)mEq/day p=0.042, postmenopausal women: 152 (0w) → 128m (16w)Eq/day p=0.016, older men: 181 (0w) → 145 (16w)mEq/day p=0.019). Also, urine volume was significantly larger in the premenopausal women than in young men in 8w and 16w (8w: 1009 vs. 980mL p=0.002, 16w: 1004 vs. 978mL, p=0.006), while it was not different between postmenopausal women and older men (8w: 1002 vs. 990 p=0.347, 16w: 1003 vs. 1001 p=0.895). The urine volume was positively correlated with BP in the premenopausal women, while it was negatively associated with BP in young men in 16w. Conclusion Although sodium intake was similarly decreased in premenopausal women and young men, urine sodium excretion did not fall, and urine volume increased in premenopausal women. This phenomenon disappeared in postmenopausal women. Augmented natriuretic and diuretic potency might contribute to lower BP in premenopausal women with nondiabetic CKD.

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The Effects of Sasang Constitutional Diet for Essential Hypertension on Blood Pressure, Fat, and Serum Lipid: on the subjects with aerobic exercise and low salt diet at the same time

Journal of Korean Academy of Nursing ◽

10.4040/jkan.2002.32.5.673 ◽

2002 ◽

Vol 32 (5) ◽

pp. 673 ◽

Cited By ~ 5

Author(s):

Eun Young Jeon

Keyword(s):

Blood Pressure ◽

Essential Hypertension ◽

Aerobic Exercise ◽

Serum Lipid ◽

Salt Diet ◽

Low Salt

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Long-term low salt diet increases blood pressure by activation of the renin-angiotensin and sympathetic nervous systems

Clinical and Experimental Hypertension ◽

10.1080/10641963.2018.1545850 ◽

2018 ◽

Vol 41 (8) ◽

pp. 739-746

Author(s):

Jialiang Wang ◽

Yi Deng ◽

Xue Zou ◽

Hao Luo ◽

Pedro A. Jose ◽

...

Keyword(s):

Blood Pressure ◽

Salt Diet ◽

Nervous Systems ◽

Renin Angiotensin ◽

Sympathetic Nervous Systems ◽

Low Salt ◽

Sympathetic Nervous

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Abstract 495: A Novel Test for Low Salt Sensitivity: Angiotensin type-II Receptor Recruitment After Dopamine-1 Receptor Stimulation in Urine-Derived Renal Proximal Tubule Cells

Hypertension ◽

10.1161/hyp.60.suppl_1.a495 ◽

2012 ◽

Vol 60 (suppl_1) ◽

Author(s):

John J Gildea ◽

Staci A Keene ◽

Dylan T Lahiff ◽

Robert E Van Sciver ◽

Cynthia D Schoeffel ◽

...

Keyword(s):

Blood Pressure ◽

Flow Cytometry ◽

Clinical Study ◽

Salt Sensitivity ◽

High Salt ◽

Salt Diet ◽

Independent Events ◽

Angiotensin Type 2 Receptor ◽

Low Salt ◽

Angiotensin Type

Salt-sensitivity of blood pressure is an inappropriate increase in blood pressure following high salt intake. Subjects in our clinical study were typed according to their salt-sensitivity status into 3 categories: High-Salt-Sensitive (HSS; ≥ 7 mmHg increase in mean arterial pressure (MAP) on a high salt diet of 300 mEq of sodium, 17% prevalence), Low-Salt-Sensitive (LSS:, who paradoxically showed a ≥ 7 mmHg increase in MAP on a low salt diet of 10 mEq of sodium, 11% prevalence), and Salt-Resistant (SR, individuals who showed no significant increase in blood pressure on either diet, 72% prevalence). We previously demonstrated that LSS subjects show increased recruitment of the natriuretic dopamine-1 receptor (D1R) to the plasma membrane following a salt stimulation as compared to HSS subjects. Stimulation of the D1R in RPTC with fenoldopam (dopaminergic agonist) results in recruitment of the natriuretic angiotensin type-2 receptor (AT2R) to the cell surface. We hypothesized that LSS individuals may also demonstrate an enhanced AT2R RPTC membrane recruitment compared to HSS individuals when challenged with fenoldopam. In order to gain access to fresh RPTC from each subject, we isolated exfoliated RPTC from randomly voided urine from SR, LSS, and HSS subjects from our clinical study. We measured three subjects from each category with a minimum of three voids for each subject. We counted individual cells as independent events using both the confocal microscope (n=245) and the flow cytometer (n=5344). We found an inverse correlation between AT2R recruitment and the degree of salt-sensitivity of blood pressure. Fenoldopam stimulated AT2R recruitment as measured by confocal microscopy (y = -0.0047x + 0.4966, R2 = 0.2488, P<0.0001) and flow cytometry (y =-0.057x + 1.5645, R2=0.2912, P=0.0185). Flow cytometry provided a more sensitive diagnostic for LSS than HSS subjects. AT2R recruitment was more predictive of LSS than HSS. AT2R recruitment may be used as a rapid method to test for LSS individuals who need to be identified and encouraged to increase their sodium intake in order to avoid paradoxical hypertension.

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Abstract P201: Exposure to Stress and Low Salt Diet Increases Blood Pressure in Mice Lacking the Brain-Specific Renin Isoform Renin-b

Hypertension ◽

10.1161/hyp.72.suppl_1.p201 ◽

2018 ◽

Vol 72 (Suppl_1) ◽

Author(s):

Pablo Nakagawa ◽

Javier A Gomez ◽

Fernando De Azevedo Cruz Seara ◽

Curt D Sigmund

Keyword(s):

Blood Pressure ◽

Salt Diet ◽

Low Salt ◽

The Brain

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‘Low-Salt’ Bread as an Important Component of a Pragmatic Reduced-Salt Diet for Lowering Blood Pressure in Adults with Elevated Blood Pressure

Nutrients ◽

10.3390/nu11081725 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1725 ◽

Cited By ~ 5

Author(s):

Kevin D. Cashman ◽

Sorcha Kenny ◽

Joseph P. Kerry ◽

Fanny Leenhardt ◽

Elke K. Arendt

Keyword(s):

Blood Pressure ◽

Bone Metabolism ◽

Plasma Lipids ◽

Salt Intake ◽

Elevated Blood Pressure ◽

Elevated Blood ◽

Salt Diet ◽

Low Salt ◽

Dietary Period ◽

Reduced Salt

Reformulation of bread in terms of salt content remains an important measure to help achieve a reduction in salt intake in the population and for the prevention of hypertension and elevated blood pressure (BP). Our fundamental studies on the reduction of salt on dough and bread characteristics showed that wheat breads produced with 0.3 g salt/100 g (“low-salt”) were found to be comparable quality to that produced with the typical level of salt (1.2%). This food-based intervention trial examined, using a 5 week cross-over design, the potential for inclusion of “low-salt” bread as part of a pragmatic reduced-salt diet on BP, markers of bone metabolism, and plasma lipids in 97 adults with slightly to moderately elevated BP. Assuming all sodium from dietary intake was excreted through the urine, the intake of salt decreased by 1.7 g/day, on average, during the reduced-salt dietary period. Systolic BP was significantly lower (by 3.3 mmHg on average; p < 0.0001) during the reduced-salt dietary period compared to the usual-salt dietary period, but there was no significant difference (p = 0.81) in diastolic BP. There were no significant differences (p > 0.12, in all cases) in any of the urinary- or serum-based biochemical indices of calcium or bone metabolism or in plasma lipids between the two periods. In conclusion, a modest reduction in dietary salt intake, in which the use of “low-salt” (i.e., 0.3 g/100g) bread played a key role along with dietary advice, and led to a significant, and clinically meaningful, decrease in systolic, but not diastolic, BP in adults with mildly to moderately elevated BP.

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Resveratrol Supplementation Prevents Hypertension in Hypertensive Pregnant Rats by Increasing Sodium Excretion and Serum Nitric Oxide Level

International Journal of Hypertension ◽

10.1155/2020/4154010 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Xiaowen Jia ◽

Rong Zhang ◽

Jinzhu Guo ◽

Hua Yue ◽

Qiuxia Liu ◽

...

Keyword(s):

Nitric Oxide ◽

Blood Pressure ◽

Rat Model ◽

Sodium Excretion ◽

Urine Volume ◽

Noninvasive Blood Pressure ◽

Blood Pressure Lowering Effect ◽

Pregnant Rat ◽

Salt Diet ◽

Nitric Oxide Level

Background. Pregnancy-induced hypertension (PIH) remains a major cause of morbidity and mortality in pregnancy worldwide. This study was designed to study the blood pressure-lowering effect of resveratrol (RES) in a salt-induced hypertensive pregnant rat model. Methods. Forty female Sprague Dawley (SD) rats were randomized into 4 groups: Normal Preg (0.9% salt diet), Normal Preg + RES (0.9% salt diet plus daily oral RES for 4 weeks), Salt Preg (8% salt diet), and Salt Preg + RES (8% salt diet plus daily oral RES for 4 weeks). Noninvasive blood pressure was recorded on gestational days 7 and 14. On the gestational day 19, foetuses were weighed, and blood and urine samples were harvested for electrolytes and biochemical assays. Results. RES significantly reduced SBP, DBP, and MAP on gestational days 7 and 14 in the Salt Preg + RES group compared to the Salt Preg group (all P<0.05). Compared to the Salt Preg group, the foetal weight, serum NO level, urinary sodium, and 24 hour urine volume were significantly increased in the Salt Preg + RES group (all P<0.05). On the contrary, the levels of serum urea, serum creatinine, and urinary protein were significantly decreased in the Salt Preg + RES group compared to the Salt Preg group (all P<0.05). Conclusions. RES decreases blood pressure in a hypertensive pregnant rat model. Increasing sodium excretion and serum nitric oxide level might be, at least part of, the underlying mechanisms.

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Prolonged NOS inhibition in the brain elevates blood pressure in normotensive rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.275.2.r410 ◽

1998 ◽

Vol 275 (2) ◽

pp. R410-R417 ◽

Cited By ~ 4

Author(s):

Atsushi Sakima ◽

Hiroshi Teruya ◽

Masanobu Yamazato ◽

Rijiko Matayoshi ◽

Hiromi Muratani ◽

...

Keyword(s):

Blood Pressure ◽

Salt Intake ◽

High Salt ◽

Salt Loading ◽

Salt Diet ◽

Intracerebroventricular Infusion ◽

Air Jet ◽

Sd Rats ◽

Low Salt ◽

The Brain

Systemic inhibition of nitric oxide synthase (NOS) evokes hypertension, which is enhanced by salt loading, partly via augmented sympathetic activity. We investigated whether inhibition of brain NOS elevates blood pressure (BP) in normotensive rats and, if so, whether the BP elevation is enhanced by salt loading. After a 2-wk low-salt (0.3%) diet, male Sprague-Dawley (SD) rats were divided into four groups. Groups 1 and 2 received a chronic intracerebroventricular infusion of 0.5 mg ⋅ kg−1 ⋅ day−1of N G-monomethyl-l-arginine (l-NMMA), and groups 3 and 4 were given artificial cerebrospinal fluid (aCSF). Groups 1 and 3 were placed on a high-salt (8%) diet, whereas groups 2 and 4 were on a low-salt diet. On day 9or 10, group 1 showed significantly higher mean arterial pressure (MAP) in a conscious unrestrained state (129 ± 3 mmHg vs. 114 ± 3, 113 ± 1, and 108 ± 3 mmHg in groups 2, 3, and 4, respectively, P < 0.05). On a high-salt diet, response of renal sympathetic nerve activity but not of BP to air-jet stress was significantly larger in rats givenl-NMMA than in rats given aCSF (29 ± 4% vs. 19 ± 3%, P < 0.05). When the intracerebroventricular infusions were continued for 3 wk, MAP was significantly higher in rats givenl-NMMA than in rats given aCSF irrespective of salt intake, although the difference was ∼7 mmHg. Thus chronic inhibition of NOS in the brain only slightly elevates BP in SD rats. Salt loading causes a more rapid rise in BP. The mechanisms of the BP elevation and its acceleration by salt loading remain to be elucidated.

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