Distal Lithium Reabsorption in the Sodium-Restricted Rat is Not Dependent on the Urinary Sodium to Lithium Concentration Ratio

1990 ◽  
Vol 79 (2) ◽  
pp. 109-112 ◽  
Author(s):  
Michael Shalmi ◽  
Jørgen S. Petersen ◽  
Klaus Thomsen ◽  
Sten Christensen
Keyword(s):  
Concentration Ratio ◽  
Sodium Intake ◽  
Lithium Concentration ◽  
Fractional Excretion ◽  
Urinary Sodium ◽  
Control Group ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Restricted Group

1. High fractional reabsorption of lithium occurs when rats and dogs are given a low sodium diet. This has been suggested to be due to the low tubular fluid sodium to lithium concentration ratio which arises during sodium restriction allowing transport mechanisms along the distal nephron segment to accept significant quantities of lithium instead of sodium by simple competition. 2. Clearance experiments in conscious water-loaded Wistar rats maintained on either a low sodium (6 mmol/kg) or a normal sodium (120 mmol/kg) diet were performed. The rats were infused with a solution of 120 mmol/l glucose and 10 mmol/l NaCl at a rate of 6 ml/h. 3. The median fractional excretion of lithium was 19.4% in the group with a normal sodium intake, and 2.5% in the group given a low sodium diet. The urine to plasma concentration ratio of lithium was 2.5 in the normal sodium group and 0.4 in the sodium-restricted group. The urinary sodium to lithium concentration ratio was 13 in the control group and 63 in the sodium-restricted group. 4. It is concluded that the increased fractional reabsorption of lithium initiated by a low sodium intake is not likely to be due to simple competition at distal tubular nephron sites between lithium and sodium.

Abstract 17541: An Education Intervention Focused on Self-monitoring for Symptom and Sodium Intake Improves Adherence to the Low Sodium Diet and Health Outcome in Patients with Heart Failure

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Eun Kyeung Song ◽  
Debra K Moser ◽  
Seok-Min Kang ◽  
Terry A Lennie
Keyword(s):  
Health Outcomes ◽  
Cox Regression ◽  
Sodium Intake ◽  
Control Group ◽  
Education Intervention ◽  
Self Monitoring ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Patients With Heart Failure

Background: Despite the clinical emphasis on recommending a low sodium diet (LSD), adherence to a LSD remains poor in patients with heart failure (HF). Additional research is needed to determine successful interventions to improve adherence to a LSD and health outcomes. Purpose: To determine the effect of an education intervention on adherence to a LSD and health outcomes. Method: A total of 109 HF patients (age 64±9 years, 29% female) who were non-adherent to LSD, indicating > 3g of 24-hour urinary sodium excretion (24hr UNa) at baseline, were randomly assigned to one of 3 groups: 1) symptom monitoring and restricted 3 gram sodium diet (SMART) group, 2) the telephone monitoring (TM) group, or 3) usual care control group. The SMART group received individualized teaching and guidance of self-monitoring for worsening symptom and sodium intake using symptom and food diary for 4 sessions over 8 weeks. Patients assigned to either of the 2 intervention groups (SMART or TM) received phone calls every 2 weeks over 8 weeks. At 6 months follow-up, adherence to a LSD was assessed using 24hr UNa. Patients were followed for 1 year to determine time to first event of hospitalization or death due to cardiac problems. Repeated measures ANOVA and Cox regression were used to determine the effect of intervention. Results: The SMART group (n=37) showed a significant reduction in sodium intake across time compared to the TM group (n=35) and control group (n=37) (p= .022). In the Cox regression, patients in the SMART group had longer cardiac event-free survival compared to the control group after controlling for age, gender, ejection fraction, angiotensin-converting enzyme inhibitor use, and better blocker use (p=.008). Conclusion: An education intervention focused on self-monitoring for symptom and sodium intake improved adherence to LSD and health outcomes in patients with HF. Helping patients engage in self-monitoring for symptom and sodium intake by themselves can promote better health outcome.

Adrenergic control of renin during dietary sodium deprivation in conscious dogs

1989 ◽  
Vol 256 (6) ◽  
pp. E863-E871 ◽  
Author(s):  
H. Hisa ◽  
Y. H. Chen ◽  
K. J. Radke ◽  
J. L. Izzo ◽  
C. D. Sladek ◽  
...  
Keyword(s):  
Sodium Intake ◽  
Conscious Dogs ◽  
Dietary Sodium ◽  
Sodium Restriction ◽  
Adrenergic Stimulation ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Dietary Sodium Restriction

These experiments evaluated the contribution of alpha- and beta-adrenergic stimulation to plasma renin activity (PRA) during early and long-term dietary sodium restriction, compared with normal sodium intake. Uninephrectomized conscious dogs with catheters in the aorta, vena cava, and remaining renal artery were studied during normal sodium diet (approximately 70 meq/day), after 2-3 days of low-sodium diet (5-7 meq/day), and after greater than or equal to 2 wk of low-sodium diet. Direct renal arterial (ira) infusion of phenoxybenzamine plus propranolol decreased PRA by similar proportions (39-48%) during all three states of dietary sodium intake. The PRA achieved after adrenergic blockade remained higher (P less than 0.05) during early and long-term sodium restriction than during normal sodium intake. The effect on PRA of ira infusion of propranolol alone was not different from that of phenoxybenzamine plus propranolol during normal or low-sodium diet, and the magnitude of decrease in PRA during low-sodium diet was the same whether propranolol (1 microgram.kg-1.min-1) was infused ira or intravenously. In summary, beta-adrenergic stimulation accounts for similar proportions of PRA during early and long-term dietary sodium restriction and during normal sodium intake. Renal alpha-adrenoceptors appear to play little or no role in control of PRA under these conditions.

Alterations in Cerebrospinal Fluid Angiotensin II by Sodium Intake in Patients with Essential Hypertension

1989 ◽  
Vol 77 (4) ◽  
pp. 389-394 ◽  
Author(s):  
Minoru Kawamura ◽  
Yuhei Kawano ◽  
Kaoru Yoshida ◽  
Masahito Imanishi ◽  
Satoshi Akabane ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Essential Hypertension ◽  
Sodium Intake ◽  
Ang Ii ◽  
Sodium Depletion ◽  
High Sodium ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium

1. Angiotensin (ANG) levels were measured in the cerebrospinal fluid of 15 patients with essential hypertension on a high sodium diet for 1 week and on a low sodium diet for a further week. ANGs were determined using a system of extraction by Sep-Pak cartridges followed by h.p.l.c. combined with radioimmunoassay. 2. Sodium depletion resulted in increases of ANG II in the cerebrospinal fluid from 1.16 ± 0.38 (sem) to 1.83 ± 0.43 fmol/ml (P < 0.01) and of ANG III from 0.65 ± 0.11 to 0.86 ± 0.15 fmol/ml (P < 0.01). 3. The ANG II level in the cerebrospinal fluid was found to be unchanged and recovery of added ANG II was approximately 90%, even after incubation for 3 h, on both diets. Thus, it is unlikely that ANG II is produced or degraded in the cerebrospinal fluid in vitro. 4. There was no significant correlation between the cerebrospinal fluid and the plasma ANG II concentration on the low sodium diet. 5. These results suggest that the cerebrospinal fluid ANG II level increases with sodium depletion, and that the effect of the level of ANG II on the activity of the angiotensin-forming system in the central nervous system may be assessed by determination of ANG II in the cerebrospinal fluid in patients with essential hypertension.

Effect of Captopril on Renal Vascular Tone in Patients with Essential Hypertension

1979 ◽  
Vol 57 (s5) ◽  
pp. 421s-423s ◽  
Author(s):  
A. Mimran ◽  
H. R. Brunner ◽  
G. A. Turini ◽  
B. Waeber ◽  
D. Brunner
Keyword(s):  
Essential Hypertension ◽  
Vascular Tone ◽  
Sodium Intake ◽  
Renal Plasma Flow ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Urinary Potassium ◽  
Renal Vascular ◽  
Renal Vascular Tone

1. The effect of acute inhibition of angiotensin-converting enzyme by captopril (50 mg) on renal haemodynamics and function was assessed in nine patients with essential hypertension on unrestricted sodium intake (n = 8) or low sodium diet (n = 1). 2. Captopril induced a rapid and significant decrease in arterial pressure, which was maximal within 60 min. 3. Effective renal plasma flow (ERPF) increased, glomerular filtration rate (GFR) did not change and filtration fraction (FF) decreased after captopril. No change in sodium excretion and a decrease in urinary potassium occurred. 4. In the patient on low sodium diet, captopril induced striking increases in GFR and ERPF (64 and 106% respectively). 5. The logarithm of baseline plasma renin activity was positively correlated with the change in ERPF and negatively correlated with changes in FF and renal resistance. 6. The results indicate that in patients with essential hypertension angiotensin participates actvely in the maintenance of renal vascular tone at the efferent arteriolar level. A possible influence of kinins remains to be defined.

The Effect of a Reduced Sodium Intake on Post-Renal Transplantation Hypertension in Rats

1984 ◽  
Vol 66 (3) ◽  
pp. 269-276 ◽  
Author(s):  
M. H. De Keijzer ◽  
A. P. Provoost ◽  
E. D. Wolff ◽  
W. J. Kort ◽  
I. M. Weijma ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Sodium Intake ◽  
Plasma Renin ◽  
Normal Diet ◽  
Transplant Recipients ◽  
Plasma Renin Concentration ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium

1. In an experimental model of post-renal transplantation hypertension in rats, we studied the effect of a reduction of sodium intake on the development of this type of hypertension. 2. Systolic blood pressure, plasma- renin concentration and renal function were measured regularly in recipients of an allogeneic kidney transplant that had previously undergone active immunological enhancement. 3. Transplant recipients on a normal diet showed a rise in systolic blood pressure during the second week after transplantation. The systolic blood pressure of recipients on a low sodium diet remained normotensive throughout the 15 weeks follow-up period. 4. The plasma renin concentration was low in the hypertensive recipients on a normal diet, as compared with unilaterally nephrectomized controls. Although the plasma renin concentration of recipients on a low sodium diet fell below that of unilaterally nephrectomized controls on a low sodium diet, it was higher than that of recipients on a normal diet. 5. The renal function of transplant recipients was greatly reduced compared with that of control rats. The glomerular filtration rate was reduced to a greater extent than the effective renal plasma flow. 6. In a separate experiment it was revealed that a similar reduction in the glomerular filtration rate of kidneys permanently damaged by temporary ischaemia did not result in an increase in the systolic blood pressure. 7. Survival up to 6 weeks after transplantation was the same for both groups of recipients. Recipients on a low sodium diet, however, showed a better 15 weeks survival, probably owing to the absence of hypertension in this group. 8. The prevention of the development of hypertension by means of a reduction of sodium intake, points to an involvement of sodium retention in this post-transplantation hypertension model.

scholarly journals The Feasibility of Using Computrition Software for Nutrition Research

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1177-1177
Author(s):  
Courtney Millar ◽  
Alegria Cohen ◽  
Stephen Juraschek ◽  
Abby Foley ◽  
Misha Shtivelman ◽  
...  
Keyword(s):  
Pilot Study ◽  
Small Sample ◽  
Urinary Sodium ◽  
Nutrition Intervention ◽  
Calorie Intake ◽  
Double Blind ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Nutrition Research

Abstract Objectives Computrition is a food service software utilized by dieticians in clinical settings to create recipes, design menus, and scale the menus to larger quantities, yet it is underutilized in the research setting. The objective was to determine the practicality of administering two meal plans (low sodium vs typical sodium) designed with Computrition in a double-blind, randomized pilot study in older adult residents of a congregate housing facility. Methods This pilot study included 19 females and 1 male aged ≥65y residing at Jack Satter House, Revere, MA. Participants were randomized to low sodium or typical sodium meals (&lt;0.95 or &gt;2 mg/kcal), designed with Computrition. A base 7-day meal plan (with breakfast, lunch, dinner, and two snacks) was generated. Recipes entered in Computrition were modified to reach three calorie levels (1750, 2000, 2250 kcal/d) and two sodium densities, while keeping potassium levels constant at ∼3500 mg/d. Finally, Computrition labels were generated to execute meals while maintaining blinding. To determine efficacy of these meal plans, compliance was evaluated by comparing change in urinary sodium (mmol/L) over 2-weeks between low sodium vs. typical sodium groups. These comparisons were also assessed in sub-groups by calorie intake (≤1750 kcal/d, n = 12 and ≥2000 kcal/d, n = 8). Results Mean age was 77 ± 6y and calorie intake was 1849 kcal (low sodium group, n = 11) and 80 ± 9y and 1785 kcal (typical sodium group, n = 9). Over 2-weeks, urinary sodium decreased by −30.6 mmol/L in the low sodium diet, compared to 2.4 mmol/L in the typical sodium diet (P = 0.003). In those consuming ≤ 1750 kcal/d on the low sodium diet, urinary sodium decreased non-significantly by −18.3 mmol/L, compared to −2.3 mmol/L in the typical sodium diet (P = 0.16). In those consuming ≥2000 kcal/d on the low sodium diet, urinary sodium decreased non-significantly by −22.0 mmol/L, compared to no change in the typical sodium diet (P = 0.26). Conclusions In this study, two sodium meal plans designed using Computrition altered urinary sodium over 2 weeks. Similar trends in reduction were seen in the sub-groups by calorie intake, although results were not significant due to small sample sizes. Future work should evaluate testing and standardization of this software for a multi-site nutrition intervention study. Funding Sources ISAC, Marcus Institute, Hebrew SeniorLife.

Effect of Chronic Hemorrhage on Urinary Aldosterone-Like Activity and Sodium Excretion in Dogs

1957 ◽  
Vol 189 (1) ◽  
pp. 181-184 ◽  
Author(s):  
M. Jay Goodkind ◽  
Wilmot C. Ball ◽  
James O. Davis
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Sodium Excretion ◽  
Filtration Rate ◽  
Sodium Intake ◽  
Sodium Content ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Renal Sodium Excretion

Chronic hemorrhage in normal dogs resulted in increased urinary aldosterone-like activity and a reduction in renal sodium excretion which was approximately equivalent to the sodium content of the blood removed. Glomerular filtration rate either increased or did not change. A comparable increase in aldosterone-like activity was observed in urine from normal dogs fed a low sodium diet equivalent to the net sodium intake of dogs subjected to hemorrhage.

Dietary sodium intake modulates renal excretory responses to intrarenal angiotensin (1–7) administration in anesthetized rats

2013 ◽  
Vol 304 (3) ◽  
pp. R260-R266 ◽  
Author(s):  
Julie O'Neill ◽  
Alan Corbett ◽  
Edward J. Johns
Keyword(s):  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Sodium Intake ◽  
Dietary Sodium ◽  
High Sodium ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Renal Hemodynamic

Angiotensin II at the kidney regulates renal hemodynamic and excretory function, but the actions of an alternative metabolite, angiotensin (1–7), are less clear. This study investigated how manipulation of dietary sodium intake influenced the renal hemodynamic and excretory responses to intrarenal administration of angiotensin (1–7). Renal interstitial infusion of angiotensin (1–7) in anesthetized rats fed a normal salt intake had minimal effects on glomerular filtration rate but caused dose-related increases in urine flow and absolute and fractional sodium excretions ranging from 150 to 200%. In rats maintained for 2 wk on a low-sodium diet angiotensin (1–7) increased glomerular filtration rate by some 45%, but the diuretic and natriuretic responses were enhanced compared with those in rats on a normal sodium intake. By contrast, renal interstitial infusion of angiotensin (1–7) in rats maintained on a high-sodium intake had no effect on glomerular filtration rate, whereas the diuresis and natriuresis was markedly attenuated compared with those in rats fed either a normal or low-sodium diet. Plasma renin and angiotensin (1–7) were highest in the rats on the low-sodium diet and depressed in the rats on a high-sodium diet. These findings demonstrate that the renal hemodynamic and excretory responses to locally administered angiotensin (1–7) is dependent on the level of sodium intake and indirectly on the degree of activation of the renin-angiotensin system. The exact way in which angiotensin (1–7) exerts its effects may be dependent on the prevailing levels of angiotensin II and its receptor expression.

Long-Term Adherence to Low-Sodium Diet in Patients With Heart Failure

2017 ◽  
Vol 39 (4) ◽  
pp. 553-567 ◽  
Author(s):  
Misook L. Chung ◽  
Linda Park ◽  
Susan K. Frazier ◽  
Terry A. Lennie
Keyword(s):  
Heart Failure ◽  
Patient Adherence ◽  
Sodium Intake ◽  
Dietary Sodium ◽  
Factors Affecting ◽  
Sodium Diet ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Positive Attitudes

Although following a low-sodium diet (LSD) for heart failure (HF) has been recommended for decades, little is known about factors related to long-term patient adherence. The purposes of this study were to (a) compare sodium intake and factors affecting adherence in a long-term adherent group and in a non-adherent group and (b) examine predictors of membership in the long-term adherent group. Patients with HF ( N = 74) collected 24-hr urine samples and completed the Dietary Sodium Restriction Questionnaire and the Patient Health Questionnaire-9. Long-term adherence was determined using the Stage of Dietary Behavior Change Scale. The long-term adherent group had lower sodium intake (3,086 mg vs. 4,135 mg, p = .01) and perceived more benefits from LSD than the non-adherent group. Only positive attitudes toward LSD predicted membership in the long-term adherence group (odds ratio [OR] = 1.18, p = .005). Interventions focused on enhancing positive perceptions of the benefits of an LSD may improve long-term dietary adherence in patients with HF.

Sign in / Sign up

Export Citation Format

Share Document