Effects of altered dietary sodium intake on hormonal profiles in salt-sensitive hypertensive rats

1990 ◽  
Vol 127 (2) ◽  
pp. 243-248 ◽  
Author(s):  
N. Hazon ◽  
I. W. Henderson
Keyword(s):  
Blood Pressure ◽  
Sodium Intake ◽  
Control Diet ◽  
Plasma Concentrations ◽  
Plasma Renin ◽  
Dietary Sodium ◽  
Deficient Diet ◽  
Slow Increase ◽  
Group A ◽  
Group B

ABSTRACT Blood pressure and selected putatively influential hormones were measured in Brattleboro rats which were without diabetes insipidus and which were subjected to various manipulations in dietary sodium intake. Rats fed a control diet from weaning to 16 weeks of age showed a slow increase in blood pressure whereas rats fed a sodium-enriched diet for the same period exhibited sustained hypertension (115±3 versus 169±5 (s.e.m.) mmHg). In animals fed a sodium-enriched diet plasma concentrations of antidiuretic hormone (ADH) were significantly increased from 55±8 to 108±5 fmol/l. Rats fed the control diet from weaning (group A) and subsequently maintained on that diet or changed to a sodium-enriched diet or sodium-deficient diet showed no differences in their blood pressure. Plasma hormone concentrations were similar in these groups, with the exception of aldosterone suppression in rats switched from control to a sodium-enriched diet (0·26±0·04 versus 0·08±0·03 nmol/l; P <0·001). Animals fed the sodium-enriched diet from weaning to 16 weeks of age (group b) and either maintained on that diet or changed to a control diet showed little change in their established hypertension. Transfer to the control diet was associated with increased plasma renin concentrations (PRC) (13·8±2·1 to 122·6±6·2 nmol/l) and plasma aldosterone concentrations (0·04±0·01 to 0·08±0·01 nmol/l; P<0·001) but corticosteroids and ADH concentrations were unchanged. Rats maintained on the sodium-enriched diet from weaning to 16 weeks of age and transfered to a sodium-deficient diet exhibited increases in their established hypertensive blood pressures (maximally 205±4 versus 170±4 mmHg) together with significant increases in PRC (13·8 ±2·1 to 297±79 nmol/l; P< 0·001), aldosterone (0·04±0·01 to 0·23±0·07 nmol/l; P <0·001) and ADH (82·9±15·5 to 466±118 fmol/l; P <0·001), although plasma concentrations of corticosteroids were again unaffected. Thus it would appear that there is a critical developmental stage at which exposure to a sodium-enriched diet subsequently leads to hypertension. Abrupt withdrawal of the sodium-enriched diet produces an exaggerated hypertension involving changes in both ADH and the renin-angiotensin-aldosterone system. Journal of Endocrinology (1990) 127, 243–248

Sodium intake and the effects of isoproterenol and exercise on plasma renin in man

1978 ◽  
Vol 45 (6) ◽  
pp. 870-874 ◽  
Author(s):  
F. H. Leenen ◽  
P. Boer ◽  
G. G. Geyskes
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systolic Blood Pressure ◽  
Diastolic Blood Pressure ◽  
Sodium Intake ◽  
Plasma Renin ◽  
Dynamic Exercise ◽  
Dietary Sodium ◽  
Sodium Restriction ◽  
Dietary Sodium Restriction

Changes in heart rate, blood pressure, and plasma renin activity (PRA) were assessed during infusion of increasing doses of isoproterenol and during increasing work loads of dynamic exercise in five normal young men. Studies were performed at three levels of dietary sodium restriction: normal, moderately, and more severely restricted. Isoproterenol induced the expected dose-related increases in heart rate, systolic blood pressure, and PRA and decreases in diastolic blood pressure. Changes in dietary sodium intake affected these changes only to a minor degree. Dynamic exercise also induced the expected work-load-related increases in heart rate, systolic blood pressure, and PRA and decreases in diastolic blood pressure. Also these changes were not significantly affected by changes in dietary sodium intake. Apparently dietary sodium restriction does not sensitize the renin-releasing mechanisms to sympathetic stimulation.

Role of renal nerves in maintaining sodium balance in unrestrained conscious rats

1985 ◽  
Vol 249 (6) ◽  
pp. F819-F826 ◽  
Author(s):  
E. Fernandez-Repollet ◽  
C. R. Silva-Netto ◽  
R. E. Colindres ◽  
C. W. Gottschalk
Keyword(s):  
Blood Pressure ◽  
Renal Denervation ◽  
Sodium Intake ◽  
Plasma Renin ◽  
Dietary Sodium ◽  
Sodium Balance ◽  
Renal Nerves ◽  
Sodium Restriction ◽  
Low Sodium ◽  
Dietary Sodium Restriction

This study was designed to investigate the effects of bilateral renal denervation on sodium and water balance, the renin-angiotensin system, and systemic blood pressure in unrestrained conscious rats maintained on a normal- or low-sodium diet. Renal denervation was proven by chemical and functional tests. Both bilaterally denervated rats (n = 18) and sham-denervated rats (n = 15) maintained positive sodium balance while on a normal sodium intake. Both groups were in negative sodium balance for 1 day after dietary sodium restriction was instituted but were in positive sodium balance for the following 9 days. Systolic blood pressure was higher in sham-denervated (115 +/- 3 mmHg) than in denervated rats (102 +/- 3 mmHg) while on a normal diet (P less than 0.05) and remained so during sodium restriction. Plasma renin concentration (PRC) and plasma aldosterone concentration (PAC) were significantly diminished in the denervated rats during normal sodium intake (P less than 0.05). After dietary sodium restriction, PRC increased in both groups but remained significantly lower in the denervated rats (P less than 0.05). Following dietary sodium restriction, PAC also increased significantly to levels that were similar in both groups of rats. These results demonstrate that awake unrestrained growing rats can maintain positive sodium balance on a low sodium intake even in the absence of the renal nerves. However, efferent renal nerve activity influenced plasma renin activity in these animals.

The relative importance of glucocorticoids and mineralocorticoids in the development of adrenal regeneration hypertension in rats

1986 ◽  
Vol 112 (3) ◽  
pp. 389-395 ◽  
Author(s):  
C.J. Kenyon ◽  
S. A. Clark ◽  
J. A. M. Hannah ◽  
C. D. Holloway ◽  
M. C. Ingram ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Sodium Intake ◽  
Plasma Concentrations ◽  
Pressure Rise ◽  
Plasma Renin ◽  
Zona Fasciculata ◽  
Body Sodium ◽  
Lower Blood ◽  
Induced Hypertension ◽  
Pressure Changes

Abstract. The adrenocortical tissue which regenerates after adrenal enucleation, and contralateral uninephrectomy and adrenalectomy, resembles histologically zona fasciculata tissue which normally synthesises glucocorticoids. However, increases in blood pressure after enucleation (adrenal regeneration hypertension – ARH) were preceded by a rise in exchangeable body sodium similar to that found with mineralocorticoid-induced hypertension (e.g. DOC/salt rat model). Glucocorticoid involvement in ARH rats was tested, firstly by infusing dexamethasone into control and ARH rats to see whether ACTH suppression would lower blood pressure by reducing adrenocortical activity and, secondly, by infusing dexamethasone into rats with intact adrenals to see whether conditions for ARH (i.e. uninephrectomy and/or saline consumption) pre-disposed rats to the hypertensinogenic properties of glucocorticoids. Low-dose dexamethasone infusions (10 μg/day for 5 days) in ARH rats did not affect blood pressure but in control animals caused a significant (P < 0.01) increase from 128 ± 3 to 151 ± 5 mmHg. Corticosterone, 18-hydroxycorticosterone and deoxycorticosterone plasma concentrations were suppressed in both groups by dexamethasone treatment; plasma renin concentrations were lower in ARH rats than in controls. Uninephrectomy or 1% NaCl as drinking fluid did not affect the blood pressure rise induced by sc infusion of 10 μg dexamethasone/day for 14 days in rats with intact adrenals. The temporal relationship between blood pressure changes and exchangeable body sodium in ARH rats resembles that in mineralocorticoid-induced hypertension. Glucocorticoid, unlike mineralocorticoid, induced hypertension is not affected by a reduction in renal mass or increased sodium intake.

Some Aspects of the Dietary Sodium Intake on the Regulation of Aldosterone Biosynthesis in Rat Adrenals

1974 ◽  
Vol 52 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Jean-Guy Lehoux ◽  
Thomas Sandor ◽  
I. W. Henderson ◽  
I. Chester Jones
Keyword(s):  
Sodium Intake ◽  
Control Diet ◽  
Dietary Sodium ◽  
Deficient Diet ◽  
Sodium Deficiency ◽  
Rat Adrenals ◽  
In Vitro Biosynthesis ◽  
Association Time ◽  
Cytochrome P 450

Experiments were performed to study the effect of dietary sodium deficiency on the in vitro biosynthesis of corticosteroids from tritiated cholesterol by homogenates of whole adrenal glands and on the properties of rat adrenocortical cytochrome P-450. Adrenal homogenates of rats kept on a sodium deficient diet for 17 days converted 3 times more tritiated cholesterol to corticosterone, 15 times more to 18-hydroxycorticosterone, and 6 times more to aldosterone than did homogenates from rats kept on the control diet. While adrenocortical cytochrome P-450 content did not differ significantly in the glands of experimental animals from that of control animals, changes could be observed in the cytochrome P-450 – carbon monoxide association time constants (KCO).

Pharmacokinetics and Safety Assessment of Anti-HIV Dapivirine Vaginal Microbicide Rings with Multiple Dosing

2020 ◽  
Author(s):  
Lungwani Muungo
Keyword(s):  
Ex Vivo ◽  
Oral Treatment ◽  
Plasma Concentrations ◽  
Vaginal Ring ◽  
Vaginal Fluid ◽  
Cervical Tissue ◽  
Double Blind ◽  
Group A ◽  
Group B ◽  
Anti Hiv

Objectives: Self-administered vaginal rings are a promising method for delivery of topical anti-HIV microbicidesand might offer an adherence advantage over daily or coitally-dependent dosage forms such as gels. This trialassessed the safety and pharmacokinetic aspects of the Dapivirine Vaginal Ring-004 when worn as multiple rings oversequential periods of ring use by healthy, sexually-active, HIV-negative women.Methods: This double-blind trial was conducted among 48 women (18-40 years). Participants were randomlyassigned to two groups (A or B) and received (3:1) either the dapivirine or a placebo vaginal ring. Group A used tworings over a 56-day period and Group B used three rings over a 57-day period. Safety evaluations were conductedthroughout the trial. Dapivirine concentrations were measured in plasma, vaginal fluid and cervical tissue samplescollected during and after the 56 days (Group A) or 57 days (Group B) of vaginal ring use.Results: Ring-004 was safe and well tolerated in all participants. The pharmacokinetic profile demonstrated arapid increase in plasma and vaginal fluid concentrations and achieved concentrations in vaginal fluids and cervicaltissue well above the in vitro IC99 in cervical tissue (3.3 ng/mL) that were sustained for a 28 to 35-day ring use period(approximately 3000 times higher in vaginal fluids and 14 -1000 times higher in cervical tissue). Drug levels wereassociated with significant inhibitory activity of genital secretions against HIV ex vivo, a biomarker of pharmacodynamics.Individual plasma dapivirine concentrations did not exceed 553 pg/mL and were well below plasma concentrations atthe maximum tolerated dose for oral treatment (mean Cmax 2286 ng/mL).Conclusions: The consecutive use of several rings over a period of up to 57 days was safe and well tolerated, andPK data indicate that a single Ring-004 is likely to be protective for at least 35 days.

Bioinformatics Study on Serum Triglyceride Levels for Analysis of a Potential Risk Factor Affecting Blood Pressure Variability

2019 ◽  
Vol 14 (5) ◽  
pp. 376-385 ◽  
Author(s):  
Lin Xu ◽  
Jiangming Huang ◽  
Zhe Zhang ◽  
Jian Qiu ◽  
Yan Guo ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Blood Pressure Variability ◽  
Partial Correlation ◽  
Pearson Correlation ◽  
Target Organ Damage ◽  
Serum Triglyceride ◽  
Hypertensive Patients ◽  
Group A ◽  
Group B

Objective: The purpose of this study was to establish whether Triglycerides (TGs) are related to Blood Pressure (BP) variability and whether controlling TG levels leads to better BP variability management and prevents Cardiovascular Disease (CVD). Methods: In this study, we enrolled 106 hypertensive patients and 80 non-hypertensive patients. Pearson correlation and partial correlation analyses were used to define the relationships between TG levels and BP variability in all subjects. Patients with hypertension were divided into two subgroups according to TG level: Group A (TG<1.7 mmol/L) and Group B (TG>=1.7 mmol/L). The heterogeneity between the two subgroups was compared using t tests and covariance analysis. Results: TG levels and BP variability were significantly different between the hypertensive and non-hypertensive patients. Two-tailed Pearson correlation tests showed that TG levels are positively associated with many BP variability measures in all subjects. After reducing other confounding factors, the partial correlation analysis revealed that TG levels are still related to the Standard Deviation (SD), Coefficient of Variation (CV) of nighttime systolic blood pressure and CV of nighttime diastolic blood pressure, respectively (each p<0.05). In the subgroups, group A had a lower SD of nighttime Systolic Blood Pressure (SBP_night_SD; 11.39±3.80 and 13.39±4.16, p=0.011), CV of nighttime systolic blood pressure (SBP_night_CV; 0.09±0.03 and 0.11±0.03, p=0.014) and average real variability of nighttime systolic blood pressure (SBP_night_ARV; 10.99±3.98 and 12.6±3.95, p=0.024) compared with group B, even after adjusting for age and other lipid indicators. Conclusion: TG levels are significantly associated with BP variability and hypertriglyceridemia, which affects blood pressure variability before causing target organ damage.

The Effect of Prophylactic Ephedrine on Systemic Hypotension Caused by Induction of Anaesthesia with Propofol and Sufentanil in Elderly Hypertensive Patients: A Prospective Randomized, Double-blind Placebo-controlled Clinical Trial

2020 ◽  
Keyword(s):  
Blood Pressure ◽  
General Anesthesia ◽  
Normal Saline ◽  
Saline Group ◽  
Normal Saline Group ◽  
Hypertensive Patients ◽  
Group A ◽  
Elderly Hypertensive ◽  
Elderly Hypertensive Patients ◽  
Group B

Objective: To study the effectiveness of prophylactic ephedrine to prevent hypotension caused by induction of anesthesia with propofol and sufentanil in elderly hypertensive patients. Methodology: 70 elderly ASA grade II-III hypertensive patients undergoing elective general anesthesia were randomized into two groups to receive either intravenous ephedrine,100 ug/kg in 5ml normal saline (Group B), or an equal volume of normal saline (Group A) before induction. Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP) and Heart Rate (HR) were recorded at T0 (after entry to the operating room), T1 (1 min after induction), T2 (2 min after induction), T3 ( 3 min after induction), T4 (4 min after induction), T5 (when intubated), T6 (2 min after intubation), and T7 (at the start of the procedure), as well as the incidence of hypotension and bradycardia. Results: SBP, DBP and HR were not significantly different at T0 and were significantly different at T1 to T7 after anesthesia induction. There were statistically significant effect on hypotension and bradycardia between the two groups and group B have a lower risk of hypotension and bradycardia relative to group A. SBP and DBP decreased significantly after induction in both groups. HR decreased significantly in group A while increased in group B. Conclusion: Ephedrine pretreatment can minimize hypotension and bradycardia caused by propofol and sufentanil during the induction of general anesthesia in elderly patients with hypertension.

scholarly journals The Effects of Short-Term Changes in Sodium Intake on Plasma Marinobufagenin Levels in Patients with Primary Salt-Sensitive and Salt-Insensitive Hypertension

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1502
Author(s):  
Katarzyna Łabno-Kirszniok ◽  
Agata Kujawa-Szewieczek ◽  
Andrzej Wiecek ◽  
Grzegorz Piecha
Keyword(s):  
Blood Pressure ◽  
Diastolic Blood Pressure ◽  
Sodium Intake ◽  
Left Ventricular ◽  
Primary Hypertension ◽  
Dietary Sodium ◽  
Sodium Restriction ◽  
Short Term ◽  
Salt Loading ◽  
Dietary Sodium Restriction

Increased marinobufagenin (MBG) synthesis has been suggested in response to high dietary salt intake. The aim of this study was to determine the effects of short-term changes in sodium intake on plasma MBG levels in patients with primary salt-sensitive and salt-insensitive hypertension. In total, 51 patients with primary hypertension were evaluated during acute sodium restriction and sodium loading. Plasma or serum concentrations of MBG, natriuretic pro-peptides, aldosterone, sodium, potassium, as well as hematocrit (Hct) value, plasma renin activity (PRA) and urinary sodium and potassium excretion were measured. Ambulatory blood pressure monitoring (ABPM) and echocardiography were performed at baseline. In salt-sensitive patients with primary hypertension plasma MBG correlated positively with diastolic blood pressure (ABPM) and serum NT-proANP concentration at baseline and with serum NT-proANP concentration after dietary sodium restriction. In this subgroup plasma MBG concentration decreased during sodium restriction, and a parallel increase of PRA was observed. Acute salt loading further decreased plasma MBG concentration in salt-sensitive subjects in contrast to salt insensitive patients. No correlation was found between plasma MBG concentration and left ventricular mass index. In conclusion, in salt-sensitive hypertensive patients plasma MBG concentration correlates with 24-h diastolic blood pressure and dietary sodium restriction reduces plasma MBG levels. Decreased MBG secretion in response to acute salt loading may play an important role in the pathogenesis of salt sensitivity.

Pharmacist Impact on Physician Practices Related to Diabetes Management

2021 ◽  
Vol 8 (4) ◽  
pp. 560-575
Author(s):  
Amina Ammar ◽  
Lindsay M. Darghali ◽  
Wassim Tarraf ◽  
Helen D. Berlie ◽  
Linda A. Jaber
Keyword(s):  
Blood Pressure ◽  
Diabetes Management ◽  
Individual Treatment ◽  
Diabetic Patients ◽  
Composite Target ◽  
Physician Practices ◽  
Physical Presence ◽  
Group A ◽  
Group B ◽  
The Impact

To examine the impact of a pharmacist’s physical presence on (1) the achievement of individual and combined targets for hemoglobin A1c (A1C), blood pressure (BP), and low-density lipoprotein cholesterol (LDL-C) (composite target), and (2) physician practices in relation to the American Diabetes Association (ADA) standards of medical care.   Methods A retrospective, comparative study of randomly selected diabetic patients seen within an underserved primary care setting at least twice annually between June 1, 2018- December 31, 2019. Patients were allocated by whether they had received care in one of the physician-pharmacist clinics (Group A) or the physician-only clinic (Group B). Study outcomes included the proportion of patients achieving the composite and individual treatment targets for A1C, BP, and LDL-C.   Results A total of 394 patients were included; Majority were underserved African Americans. The composite target was attained by 20% of participants in Group A and 13% in Group B (p=0.09). There were no statistically significant differences in achievement of individual targets between groups. A significantly higher proportion of participants in Group A achieved better control of diastolic blood pressure control (85% vs. 74%), had microalbuminuria tested (50% vs. 12%), were prescribed aspirin (43% vs. 32%), and had lower utilization of non-insulin glucose-lowering agents relative to those in Group B.   Conclusion The impact of a pharmacist’s physical presence on physician practice demonstrated a general trend towards improvement in clinical outcomes related to diabetes management. Future studies are needed to further characterize the impact provided by the physician-pharmacist relationship.

Abstract P276: A High Sodium Diet Reduces Cutaneous Microvascular Function In Normotensive Individuals With Salt Sensitive Blood Pressure

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Jordan C Patik ◽  
Joseph M Stock ◽  
Nathan T Romberger ◽  
Shannon L Lennon ◽  
William B Farquhar ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Vascular Function ◽  
Sodium Intake ◽  
Local Heating ◽  
Urinary Sodium Excretion ◽  
Microvascular Function ◽  
Dietary Sodium ◽  
Heating Unit ◽  
Doppler Flowmetry ◽  
High Sodium

Impaired vascular function likely contributes to the association between dietary sodium intake and the development of cardiovascular disease. Using the cutaneous microvasculature as a model, we have previously shown that a high sodium (HS) diet blunts local heating-induced vasodilation in normotensive individuals with salt resistant (SR) blood pressure (BP). However, the effect of a HS diet on the cutaneous microvasculature in normotensive salt sensitive (SS) individuals remains unclear. Therefore, we tested the hypothesis that cutaneous microvascular function is reduced by a HS diet to a greater degree in SS compared to SR individuals. After each 7-day controlled feeding diet (low sodium (LS) = 20 mmol/day; HS = 300 mmol/day), an intradermal microdialysis fiber was inserted in the ventral forearm and perfused with Ringer’s solution. Skin blood flow (SkBF) was continuously monitored via laser Doppler flowmetry and a local heating unit was placed over the fiber and heated to 42°C until SkBF reached a stable plateau. Site-specific maximal SkBF was determined by perfusing 28mM sodium nitroprusside and heating to 43°C. Mean arterial pressure (MAP) was assessed at regular intervals on the contralateral arm and was used to calculate cutaneous vascular conductance (CVC = SkBF / MAP). Subjects wore a 24-hr ambulatory BP monitor and collected their urine on the final day of each diet. Fourteen subjects (9W / 5M, 42 ± 14 yr) whose MAP increased >5 mmHg (Δ8 ± 1 mmHg) on the HS diet were defined as SS and were compared to 14 age- (43± 14 yr) and sex-matched SR subjects (Δ1 ± 3 mmHg). SS and SR had similar MAP at baseline (88 ± 9 vs. 90 ± 8 mmHg, P = 0.88) and urinary sodium excretion was increased similarly across groups by the HS diet (Δ239 ± 104 vs. Δ220 ± 66 mmol / 24 hr, P = 0.20). Cutaneous vasodilation in response to local heating was decreased on the HS diet relative to the LS diet in both SS (Δ-9 ± 9 %CVCmax, P = 0.005) and SR (Δ-9 ± 9 %CVCmax, P=0.005); however, there was not a group x diet interaction (P = 0.99). In contrast to our hypothesis, these results suggest that the deleterious effects of high sodium diets on cutaneous microvascular function are similar in normotensive salt sensitive and salt resistant individuals.

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