scholarly journals Distinguishing Low and High Water Consumers—A Paradigm of Disease Risk

Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 858 ◽  
Author(s):  
Lawrence E. Armstrong ◽  
Colleen X. Muñoz ◽  
Elizabeth M. Armstrong
Keyword(s):  
Disease Risk ◽  
Plasma Concentrations ◽  
Urine Volume ◽  
Plasma Osmolality ◽  
High Volume ◽  
High Water ◽  
Plasma Sodium ◽  
Reference Ranges ◽  
Dietary Recommendations ◽  
Tract Infections

A long-standing body of clinical observations associates low 24-h total water intake (TWI = water + beverages + food moisture) with acute renal disorders such as kidney stones and urinary tract infections. These findings prompted observational studies and experimental interventions comparing habitual low volume (LOW) and high volume (HIGH) drinkers. Investigators have learned that the TWI of LOW and HIGH differ by 1–2 L·d−1, their hematological values (e.g., plasma osmolality, plasma sodium) are similar and lie within the laboratory reference ranges of healthy adults and both groups appear to successfully maintain water-electrolyte homeostasis. However, LOW differs from HIGH in urinary biomarkers (e.g., reduced urine volume and increased osmolality or specific gravity), as well as higher plasma concentrations of arginine vasopressin (AVP) and cortisol. Further, evidence suggests that both a low daily TWI and/or elevated plasma AVP influence the development and progression of metabolic syndrome, diabetes, obesity, chronic kidney disease, hypertension and cardiovascular disease. Based on these studies, we propose a theory of increased disease risk in LOW that involves chronic release of fluid-electrolyte (i.e., AVP) and stress (i.e., cortisol) hormones. This narrative review describes small but important differences between LOW and HIGH, advises future investigations and provides practical dietary recommendations for LOW that are intended to decrease their risk of chronic diseases.

Influence of opioid peptides on release from vasopressin and oxytocin neurones of the hypothalamoneurohypophyseal system: effects of naloxone in the conscious rat

1990 ◽  
Vol 68 (5) ◽  
pp. 568-574 ◽  
Author(s):  
Savio W. T. Cheng ◽  
Edward F. O'Connor ◽  
William G. North
Keyword(s):  
Plasma Concentration ◽  
Opioid Peptides ◽  
Plasma Concentrations ◽  
Plasma Osmolality ◽  
Plasma Sodium ◽  
Endogenous Opioid ◽  
Salt Loading ◽  
Conscious Rats ◽  
Basal Plasma ◽  
Acute And Chronic Treatments

We examined the effects of acute and chronic treatments with naloxone on release of vasopressin and oxytocin from the hypothalamoneurohypophyseal system (HNS) in conscious, chronically instrumented Long–Evans rats. Plasma concentrations of vasopressin-associated neurophysin and oxytocin-associated neurophysin were evaluated before and during an intravenous infusion of 18% saline at 100 μL∙kg−1 body weight∙min−1 for 60 min. Acute treatment with naloxone (2.75 μmol/kg, intravenous) did not measurably alter basal plasma osmolality or vasopressin-associated neurophysin concentration, but it caused a three-fold rise in basal plasma oxytocin-associated neurophysin concentration (16 ± 2 to 46 ± 3 fmol/mL, p < 0.005). Chronic treatment with naloxone (13.75 μmol/day, subcutaneous pellets) increased plasma osmolality (292 ± 1 to 300 ± 2 mosmol/kg H2O, p < 0.01) by day 5, but it had no measurable effects on basal vasopressin- or oxytocin-associated neurophysin concentration. There were also no significant differences in plasma sodium concentration (144.8 ± 1.1 vs. 142.2 ± 1.4 mequiv./L) under both conditions. Acute and chronic treatments with naloxone accompanied by salt loading produced a five- and four-fold decrease in the rates that plasma concentration of vasopressin-associated neurophysin changed with plasma osmolality, compared with untreated salt-loaded control rats. For oxytocin secretion from the HNS, both treatments accompanied by salt loading substantially decreased the threshold for changes in relation to plasma osmolality; the rise in plasma concentration of oxytocin-associated neurophysin was similar at all levels of hyperosmotic stimulation. A strongly correlated relationship between plasma oxytocin-associated neurophysin and plasma osmolality (r = 0.739) found for control animals became poorly correlated following treatments (acute, r = 0.173; chronic, r = −0.079). Our results suggest that in conscious rats, endogenous opioid peptides enhance the secretion of vasopressin from neurones of the HNS in response to hyperosmotic stimulation but inhibit both basal and stimulated release of oxytocin.Key words: naloxone, vasopressin, oxytocin, neurophysin, conscious rats.

scholarly journals Kidney Aquaporin-2 Expression during Escape from Antidiuresis Is Not Related to Plasma or Tissue Osmolality

1999 ◽  
Vol 10 (10) ◽  
pp. 2067-2075
Author(s):  
TAKASHI MURASE ◽  
CAROLYN A. ECELBARGER ◽  
ERIN A. BAKER ◽  
YING TIAN ◽  
MARK A. KNEPPER ◽  
...  
Keyword(s):  
Urine Volume ◽  
Extracellular Fluid ◽  
Plasma Osmolality ◽  
Northern Blotting ◽  
Plasma Sodium ◽  
Water Restriction ◽  
Water Loading ◽  
Aquaporin 2 ◽  
Daily Water ◽  
Tissue Osmolality

Abstract. Recent results indicate that renal escape from vasopressin-induced antidiuresis is accompanied by a marked downregulation of whole kidney aquaporin-2 (AQP-2) protein and mRNA expression. However, in those studies, the escaped animals were also markedly hypo-osmolar compared to controls as a result of water loading during antidiuresis. The present studies evaluated whether systemic or local osmolality contributes to the downregulation of AQP-2 expression in this model. In the first study, two groups of 1-deamino-[8-D-arginine]-vasopressin (dDAVP)-infused rats were water-loaded; after establishment of escape, one group was then water-restricted for 4 d to reverse the escape, whereas the other group continued daily water loading. Whole kidney AQP-2 protein was measured by Western blotting, and inner medulla AQP-2 mRNA was determined by Northern blotting. Results were compared to dDAVP-infused rats fed solid chow. After 4 d of water restriction, urine volume decreased to the same level as in the rats on solid chow; however, plasma sodium concentrations and plasma osmolality remained low. Despite maintenance of significant hypo-osmolality, rats in which escape was subsequently reversed by water restriction reestablished high dDAVP-stimulated kidney levels of AQP-2 after 4 d of water restriction.In the second study, AQP-2 expression was evaluated in different regions of kidneys from water-loaded rats undergoing escape from antidiuresis. Despite markedly different interstitial osmolalities, significant downregulation of AQP-2 expression compared to dDAVP-infused control rats was seen in the inner medulla, outer medulla, and cortex. Thus, neither systemic nor interstitial osmolality appears to appreciably be correlated with downregulation of kidney AQP-2 expression during escape from antidiuresis. These results therefore suggest that additional vasopressin- and osmolality-independent factors, likely related to the effects of extracellular fluid volume expansion, also regulate kidney AQP-2 expression in rats.

Neuroendocrine factors mediating polydipsia induced by dietary Na, Cl, and K depletion

1986 ◽  
Vol 251 (6) ◽  
pp. R1071-R1077 ◽  
Author(s):  
A. Saikaley ◽  
D. Bichet ◽  
J. Kucharczyk ◽  
L. N. Peterson
Keyword(s):  
Water Intake ◽  
Time Course ◽  
Plasma Concentrations ◽  
Urine Volume ◽  
Plasma Osmolality ◽  
Male Rats ◽  
Angiotensin Receptors ◽  
Salt Diet ◽  
Low Salt ◽  
Electrolytic Lesions

We investigated whether the increased intake of water during dietary electrolyte depletion is related to activation of the renin-angiotensin system. Young adult male rats were fed a low Na-, Cl-, K-free (low-salt) diet for 2 wk during which measurements were made of daily water intake and urine volume, plasma osmolality (Posm) and electrolytes, and plasma renin activity (PRA) and angiotensin I (ANG I) concentration. Water intake and urine output increased on day 3 of the low-salt diet, reached a maximum on day 4, and remained elevated, paralleling the time course of increases in PRA and ANG I plasma concentrations. Posm was normal after 2 days on the low-salt, although it was significantly lower by day 11. Renal concentrating ability was not different from controls after 6 days, but was significantly reduced after 11 days of treatment. Electrolytic lesions of the subfornical organ (SFO) abolished the low-salt diet-induced polydipsia, but had no effect on the diet-induced increases in PRA and plasma ANG I concentration. These data demonstrate that polydipsia induced by feeding a low-salt diet can develop in the presence of a normal or reduced Posm and precedes the development of a renal concentrating defect. The primary polydipsia is associated with elevated PRA and ANG I and appears to be mediated by angiotensin receptors in the SFO.

RE-EVALUATION OF THE CORRECTION FACTOR FOR ETHANOL IN THE CALCULATION OF THE OSMOLAL GAP

2009 ◽  
Vol 32 (6S) ◽  
pp. 5
Author(s):  
V Fung ◽  
M Pudek ◽  
F Rosenberg ◽  
D Holmes
Keyword(s):  
Correction Factor ◽  
Freezing Point ◽  
Laboratory Data ◽  
Plasma Osmolality ◽  
High Volume ◽  
Plasma Sodium ◽  
Correction Factors ◽  
Empirical Correction ◽  
Empirical Correction Factor ◽  
Osmolal Gap

Background/objectives: It is well-known that ethanol (EtOH) demonstrates non-ideal solute behaviour in plasma. This is reflected by its larger than expected contribution to the plasma osmolality. Published multiplicative correction factors for the EtOH contribution range from 1.20 to 1.25. The objective of this study is to determine an optimal correction factor specific to the instrumentation at Vancouver General (VGH) and St. Paul's (SPH) Hospitals. Methods: Laboratory data from patients presenting to the two respective emergency department between August 01, 2007 and November 30, 2008 were extracted from the Sunset database. Plasma sodium, urea, glucose, and EtOH were measured using the two high-volume chemistry analyzers employed at the sites: the Siemens (previously Dade) RXL (VGH) and the Siemens (previously Bayer) Advia 1650 (SPH). Plasma osmolality was measured by freezing-point depression and calculated (excluding the EtOH contribution) using the following standard formula (in SI units): 2 [Na] + [Urea] + [Glucose]. Patients without EtOH data or who had undetectable EtOH were excluded as were patients with methanol or ethylene glycol present. Standard regression statistics were employed. Results: Twelve hundred and fifty-three patient samples (n=823 from SPH and n=430 from VGH) were included. Empirical correction factor m, satisfying, Osmol gap (mmol/kg) =m[EtOH] (mmol/L) was consistently found to be 1.15 for VGH, SPH and both combined. Conclusions: The correction factor of 1.15 for ethanol from the current study appears to be more representative and reliable. Further studies to evaluate its validity in other hospital sites as well as its utility in screening patients with known toxic alcohol ingestion will be warranted.

Osmotic control of vasopressin with chronically altered volume states in anephric dogs

1984 ◽  
Vol 247 (3) ◽  
pp. E355-E361 ◽  
Author(s):  
E. W. Quillen ◽  
M. M. Skelton ◽  
J. Rubin ◽  
A. W. Cowley
Keyword(s):  
Plasma Osmolality ◽  
High Volume ◽  
Conscious State ◽  
Plasma Sodium ◽  
Volume State ◽  
Continuous Peritoneal Dialysis ◽  
The Relationship ◽  
Sodium And Potassium ◽  
Osmotic Stimuli

Continuous peritoneal dialysis has been used to maintain anephric dogs at chronically sustained low, normal, and high volume states in order to study the long-term interaction of volume and osmotic stimuli in the control of plasma vasopressin (PAVP). Bilaterally nephrectomized dogs were maintained for 1–3 mo with normal plasma sodium and potassium levels and blood urea nitrogen of 70.1 +/- 10.8 mg/dl. During the first month, the dogs were dialysized to each of the three volume states. After each volume state had been maintained for 7 days, an osmotic forcing with intravenous distilled H2O and hypertonic NaCl was performed in the conscious state to quantitate the relationship between plasma osmolality (Posm) and PAVP. During the osmotic forcings left atrial pressure (LAP) averaged -2.4 +/- 0.5, 2.6 +/- 0.8, and 11.9 +/- 1.1 cmH2O; mean arterial pressure averaged 113 +/- 11, 125 +/- 10, and 148 +/- 8 mmHg, both respective for the low, normal, and high volume states. The slope of the normovolemic Posm-PAVP relationship was determined to be 0.047 pg X ml-1 X mosmol-1 X kg-1, and neither the hypovolemic or hypervolemic relationships were significantly different. The results demonstrate two additional points that must be considered in the control of PAVP. First, the severely depressed sensitivity of osmotic PAVP control suggests that either the dialysis procedures or the absence of the kidneys suppressed or eliminated some factor normally important to the secretion of vasopressin.(ABSTRACT TRUNCATED AT 250 WORDS)

Osmoregulatory and Hematological Responses of Rainbow Trout (Salmo gairdneri) to Extended Environmental Acidification

1984 ◽  
Vol 41 (11) ◽  
pp. 1686-1694 ◽  
Author(s):  
M. A. Giles ◽  
H. S. Majewski ◽  
B. Hobden
Keyword(s):  
Rainbow Trout ◽  
Osmotic Pressure ◽  
Plasma Concentrations ◽  
Acid Stress ◽  
Plasma Osmolality ◽  
Hemoglobin Concentration ◽  
Ion Concentration ◽  
Salmo Gairdneri ◽  
Plasma Sodium ◽  
Hydrogen Ion Concentration

The dose-dependent relationships of several physiological responses to acid were examined in rainbow trout (Salmo gairdneri) exposed for 22 d to water at pH 4.2–6.0. Significant increases in ventilatory and cardiac rates occurred at pHw < 4.9. Hematocrit and hemoglobin concentration increased progressively with acid stress at pHw < 5.5. Plasma calcium, magnesium, sodium, and chloride concentrations were reduced and plasma phosphate elevated in acid-exposed fish. Seasonal differences were observed in the quantitative responses to acid exposure in the relationship between hematocrit and hemoglobin concentration and in the plasma concentrations of calcium and magnesium. The fractional contribution of sodium and chloride to plasma osmolality decreased linearly with increasing hydrogen ion concentration, and the change in plasma sodium, chloride, and osmolality per unit change in pHw was 35.2 mmol/L, 39.7 mmol/L, and 47.4 mosmol/kg, respectively, in the pH range of 4.5–5.2. We concluded that the discrepancy between the reduction in plasma osmotic pressure and the combined reduction in the major plasma electrolytes is a result of the elevation in concentration of an unidentified plasma solute which offsets 40–45% of the expected reduction in osmotic pressure.

Urinary Indices during Dehydration, Exercise, and Rehydration

1998 ◽  
Vol 8 (4) ◽  
pp. 345-355 ◽  
Author(s):  
Lawrence E. Armstrong ◽  
Jorge A. Herrera Soto ◽  
Frank T. Hacker ◽  
Douglas J. Casa ◽  
Stavros A. Kavouras ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Body Mass ◽  
Urine Volume ◽  
Plasma Osmolality ◽  
Body Water ◽  
Hydration Status ◽  
Plasma Sodium ◽  
Oral Rehydration ◽  
Urine Color ◽  
Better Than

This investigation evaluated the validity and sensitivity of urine color (Ucol), specific gravity (Usg), and osmolality (Uosm) as indices of hydration status, by comparing them to changes in body water. Nine highly trained males underwent a 42-hr protocol involving dehydration to 3.7% of body mass (Day 1, −2.64 kg), cycling to exhaustion (Day 2, −5.2% of body mass, −3.68 kg), and oral rehydration for 21 hr. The ranges of mean (across time) blood and urine values were Ucol, 1-7; Usg, 1.004-1.029; U08m, 117-1,081 mOsm • kg−1; and plasma osmolality (Posm), 280-298 mOsm ⋅ kg−1. Urine color tracked changes in body water as effectively as (or better than) Uosm, Usg, urine volume, Posm, plasma sodium, and plasma total protein. We concluded that (a) Ucol, Uosm, and Usg are valid indices of hydration status, and (b) marked dehydration, exercise, and rehydration had little effect on the validity and sensitivity of these indices.

Sodium Status of Collapsed Marathon Runners

2005 ◽  
Vol 129 (2) ◽  
pp. 227-230 ◽  
Author(s):  
Alexander Kratz ◽  
Arthur J. Siegel ◽  
Joseph G. Verbalis ◽  
Marvin M. Adner ◽  
Terry Shirey ◽  
...  
Keyword(s):  
Plasma Osmolality ◽  
Fluid Replacement ◽  
Hydration Status ◽  
Plasma Sodium ◽  
Reference Ranges ◽  
Finish Line ◽  
Marathon Runners ◽  
Adequate Hydration ◽  
Boston Marathon ◽  
New Guidelines

Abstract Context.—Recommendations for prevention and treatment of medical emergencies in participants in marathon races center on maintenance of adequate hydration status and administration of fluids. Recently, new recommendations for fluid replacement for marathon runners were promulgated by medical and athletic societies. These new guidelines encourage runners to drink ad libitum between 400 and 800 mL/h as opposed to the previous “as much as possible” advice. Objective.—To assess the sodium and hydration (plasma osmolality) status of collapsed marathon runners after the promulgation of new hydration guidelines. Design.—Plasma sodium and osmolality values of runners who presented to the medical tent at the finish line of the 2003 Boston Marathon were measured. Results.—Using reference ranges derived from the general population, of 140 collapsed runners, 35 (25%) were hypernatremic (sodium, &gt;146 mEq/L) and 6 (12%) were hyperosmolar (osmolality, &gt;296 mOsm/kg H2O), whereas 9 (6%) were hyponatremic (sodium, &lt;135 mEq/L) and 8 (16%) were hypo-osmolar (osmolality, &lt;280 mOsm/kg H2O). Compared with a population of marathon runners who had experienced no medical difficulties, 9% of the runners were hypernatremic, 5% were hyponatremic, 8% were hypo-osmolar, and none were hyperosmolar. Conclusions.—Our findings indicate a significant incidence of hypernatremia with hyperosmolality and hyponatremia with hypo-osmolality among collapsed runners despite the new fluid intake recommendations, suggesting that either further educational measures are required or that the new guidelines are not entirely adequate to prevent abnormalities in fluid balance. Furthermore, the immediate medical management of hypernatremia and hyponatremia is different. Administration of fluids to severely hyponatremic patients may result in fatal cerebral edema. Our findings caution against institution of treatment until laboratory tests determine the patient's sodium status.

scholarly journals Development of Fatty Acid Reference Ranges and Relationship with Lipid Biomarkers in Middle-Aged Healthy Singaporean Men and Women

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 435
Author(s):  
Cody A. C. Lust ◽  
Xinyan Bi ◽  
Christiani Jeyakumar Henry ◽  
David W. L. Ma
Keyword(s):  
Disease Risk ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Multiple Regression Model ◽  
Dietary Fatty Acids ◽  
Lipid Biomarkers ◽  
Reference Ranges ◽  
Middle Aged ◽  
Serum Samples ◽  
Biologically Relevant

Dietary fatty acids (FA) are essential for overall human health, yet individual FA reference ranges have yet to be established. Developing individual FA reference ranges can provide context to reported concentrations and whether an individual displays deficient, or excess amounts of FA. Reference ranges of sixty-seven individual FA (μmol/L) were profiled and analyzed using gas chromatography with a flame ionization detector from serum samples collected from 476 middle-aged Singaporean males (BMI:23.3 ± 2.9) and females (BMI:21.8 ± 3.6). Measures of triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol (TC) (mmol/L) were also collected. The mean FA concentration seen in this cohort (11,458 ± 2478 was similar to that of overweight North American cohorts assessed in past studies. Ten biologically relevant FA were compared between sexes, with females exhibiting significantly higher concentrations in four FA (p < 0.05). A multiple regression model revealed the ten FA contributed significantly to nearly all lipid biomarkers (p < 0.05). A majority of participants who had FA concentrations in the ≥95th percentile also exhibited TG, HDL, LDL, and TC levels in the “high” risk classification of developing cardiovascular disease. Future studies profiling individual FA reference ranges in many unique, global cohorts are necessary to develop cut-off values of individual FA concentrations highly related to disease-risk.

Is high-intensity interval training a time-efficient exercise strategy to improve health and fitness?

2014 ◽  
Vol 39 (3) ◽  
pp. 409-412 ◽  
Author(s):  
Jenna B. Gillen ◽  
Martin J. Gibala
Keyword(s):  
High Intensity ◽  
Disease Risk ◽  
Interval Training ◽  
High Volume ◽  
Oxidative Capacity ◽  
High Intensity Interval Training ◽  
Exercise Participation ◽  
Cardiometabolic Disorders ◽  
Low Volume ◽  
High Intensity Interval

Growing research suggests that high-intensity interval training (HIIT) is a time-efficient exercise strategy to improve cardiorespiratory and metabolic health. “All out” HIIT models such as Wingate-type exercise are particularly effective, but this type of training may not be safe, tolerable or practical for many individuals. Recent studies, however, have revealed the potential for other models of HIIT, which may be more feasible but are still time-efficient, to stimulate adaptations similar to more demanding low-volume HIIT models and high-volume endurance-type training. As little as 3 HIIT sessions per week, involving ≤10 min of intense exercise within a time commitment of ≤30 min per session, including warm-up, recovery between intervals and cool down, has been shown to improve aerobic capacity, skeletal muscle oxidative capacity, exercise tolerance and markers of disease risk after only a few weeks in both healthy individuals and people with cardiometabolic disorders. Additional research is warranted, as studies conducted have been relatively short-term, with a limited number of measurements performed on small groups of subjects. However, given that “lack of time” remains one of the most commonly cited barriers to regular exercise participation, low-volume HIIT is a time-efficient exercise strategy that warrants consideration by health practitioners and fitness professionals.

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