Erythrocyte Water Content Research Articles

Steady-state volumes and metabolism-independent osmotic adaptation in mammalian erythrocytes.

Erythrocytes of various mammalian species -- including human -- maintain osmotic balance with the blood plasma (osmotic activity 270-310 mosmol). However, their intracellular levels of osmotically active ions (potassium, sodium, chloride, and hydrogencarbonate), water content and osmotic resistance deviate significantly. In the present report we study the relationship among intracellular water, potassium and sodium levels of the erythrocytes of various mammalian species and in the developing calf. In addition, the osmotic resistance, K(+) (Rb(+)) uptake and the DPH fluorescence anisotropy of various erythrocytes and erythrocyte ghost membranes were correlated. The results show no statistically significant relationship between erythrocyte water content and [K(+)+Na(+)] levels or K(+)/Na(+) ratios. The reversal of erythrocyte K(+)/Na(+) ratios coincides with the decrease of steady-state ATP levels in the developing calf. The mobility of lipids within the hydrophobic inner layer of the plasma membrane relates closely to passive K(+) (Rb(+)) uptake, and plays a significant role in regulatory volume changes.

Augmented Water Binding and Low Cellular Water Content in Erythrocytes of Camel and Camelids

We investigated a link between hemoglobin primary structure, hemoglobin hydrophobicity-hydrophilicity, and erythrocyte water content in various mammalian species. Some hemoglobin molecules, particularly those of the camel and camelids, contain more charged amino acid residues and are more hydrophilic than the hemoglobins of human and a number of other mammalian species. To test the in vivo significance of these alterations of hemoglobin primary structure, we determined the osmotically unresponsive erythrocyte water fractions in mannit solutions of various osmolarities at 4°C. Among the species investigated, the size of the osmotically unresponsive erythrocyte water fraction relates in a positive linear way to hemoglobin hydrophilicity. The extreme low total erythrocyte water content of camel erythrocytes (1.1–1.3 g water/g dry mass) may be explained by a comparatively high osmotically unresponsive erythrocyte water fraction. It is proposed that alterations of hemoglobin sequences of camel and camelids may be the part of a natural selection process aimed at protecting these animals against osmotic dehydration in arid environments.

Studies on in vitro effect of free fatty acids on water content and osmotic fragility of rabbit (lepus cuniculus) erythrocytes

The effects of free fatty acids in the blood on osmotic fragility and water content of erythrocytes when combined with hyperthermia were investigated. The isotonic buffer, containing the fatty acid, was added to the erythrocyte suspension to a final concentration of 200μM/L. The samples were kept for one hour in an incubator at 37 °C or 42 °C. The osmotic fragility of erythrocytes was determined by coil planet centrifuge system and intracellular water content was measured by gasliquid chromatography. A high concentration of unsaturated fatty acid and hyperthermia caused the increase in intracellular water and the decrease in osmotic resistance of the red blood cells compared to saturated fatty acid and the control. The present experiment demonstrated that unsaturated fatty acid was one of the principal chemical and metabolic factors which caused sports anemia.

Effect of thermal stress on the water content of rabbit ( Lepus cuniculus) erythrocytes in vitro and in vivo

1. 1. The water content of rabbit erythrocytes was measured by gas-liquid chromatography to observe the effects of thermal stress on water content. 2. 2. The water content of erythrocytes was decreased immediately after 45-min whole-body heating at 42°C compared to heating at 37°C. 3. 3. The water content of erythrocytes was increased after heating in vitro at 42°C for 1 h compared with the values after treating at 37°C and the control value.

Interactions Between ion Exchange and Metabolism in Erythrocytes of the Rainbow TroutOncorhynchus Mykiss

ABSTRACTExperiments were carried out to investigate the relationship between ion exchange and energy metabolism in rainbow trout erythrocytes in vitro. Under resting conditions, the sodium/potassium pump accounts for 20% of the cellular energy budget. In the presence of the β-adrenergic agonist isoproterenol, however, this increases to 43%. Inhibition of the sodium/potassium pump with ouabain results in greater increases in erythrocyte water content and sodium and chloride concentrations and a greater decrease in erythrocyte potassium concentration following stimulation by isoproterenol. Moreover, the decrease in erythrocyte NTP levels observed following adrenergic stimulation does not occur when the sodium/potassium pump is inhibited with ouabain. Inhibition of the sodium/ potassium pump also abolishes the increase in oxygen consumption by the cells which normally takes place following adrenergic stimulation. Finally, depletion of erythrocyte NTP levels by the sodium ionophore monensin or by previous incubation with nitrogen does not result in a significant increase in oxygen consumption. Thus, catecholamines appear to be crucial for the metabolic-membrane coupling that occurs following adrenergic stimulation in rainbow trout erythrocytes.

Bepridil protects sickle cells against the adverse rheological effects of cyclical deoxygenation

Calcium influx into sickle cells, with consequential activation of the Ca2(+)-activated K+ efflux (Gardos) channel, is a potential cause of cellular dehydration and loss of deformability. Bepridil, a recently described inhibitor of the Gardos channel, was found at pharmacological concentration (1 mumol/l) to inhibit significantly (P less than 0.01) the loss of deformability when sickle cells were subjected to cycles of oxygenation-deoxygenation for 15 h at 37 degrees C. Bepridil also inhibited significantly (P less than 0.005) the formation of irreversibly sickled cells. Drugs that preserve the K+ and therefore water content of erythrocytes are of potential value for hydrotherapy of sickle cell disease.

Effect of prolonged physical exercise on intra-erythrocyte and plasma potassium.

The intracellular concentrations of sodium [Na+] and potassium [K+] and the water content in human erythrocytes were investigated in 21 male runners before and after a marathon. From 2 to 5 min after the race, the intra-erythrocyte [K+] was significantly decreased (p less than 0.001) by 7% whereas the plasma [K+], intra-erythrocyte [Na+] and the erythrocyte water content were unchanged. The change in the intra-erythrocyte [K+] observed immediately after the marathon, was negatively correlated with the race time (r = -0.44; p less than 0.05). Furthermore, the change in the plasma [K+] (r = -0.64; p less than 0.001) and the amount of K+ excreted in the urine during the race (r = 0.54; p less than 0.05) were also, respectively, negatively and positively correlated with the race time. It is concluded that during prolonged physical exercise the erythrocytes could serve as a kind of K+ reservoir that is drained with increasing magnitude of body K+ loss. This might explain why in the faster marathon runners, in whom the urinary K+ loss is smaller and the K+ intake is greater than in the slower runners during race, the intra-erythrocyte [K+] is unchanged after a marathon whereas in the slower runners it is decreased.

Linear rate of change in the product of erythrocyte water content and potassium concentration during the 0–120-hour postmortem period in the rat

An accurate and reproducible technique was employed for measurement of water content (RBC H 2O ) and potassium concentration (RBC K) in rat erythrocytes post mortem. Coefficients of variation for determination of RBC H 2O and RBC K, as estimated from the results of duplicate analyses ( n = 36), were 1.21% and 1.17%, respectively. Erythrocyte water content and RBC K were directly and linearly related ( r = +0.93( P < 0.001)), while the product of RBC H 2O and RBC K varied linearly and inversely ( r = −0.89 ( P < 0.001)) with postmortem interval (PMI) over the 0–120-h postmortem period. In addition, the standard deviations of the data points for (RBC H 2O × RBC K) remained relatively constant and independent of PMI. Attention is drawn to the possibility of determining time elapsed since death from (sequential) measurements of (RBC H 2O × RBC K) in individual cadavers.

Early fluid and protein shifts in men during water immersion.

High precision blood and plasma densitometry was used to measure transvascular fluid shifts during water immersion to the neck. Six men (28-49 years) undertook 30 min of standing immersion in water at 35.0 +/- 0.2 degrees C; immersion was preceded by 30 min control standing in air at 28 +/- 1 degrees C. Blood was sampled from an antecubital catheter for determination of blood density (BD), plasma density (PD), haematocrit (Ht), total plasma protein concentration (PPC), and plasma albumin concentration (PAC). Compared to control, significant decreases (p less than 0.01) in all these measures were observed after 20 min immersion. At 30 min, plasma volume had increased by 11.0 +/- 2.8%; the average density of the fluid shifted from extravascular fluid into the vascular compartment was 1006.3 g.l-1; albumin moved with the fluid and its albumin concentration was about one-third of the plasma protein concentration during early immersion. These calculations are based on the assumption that the F-cell ratio remained unchanged. No changes in erythrocyte water content during immersion were found. Thus, immersion-induced haemodilution is probably accompanied by protein (mainly albumin) augmentation which accompanies the intravascular fluid shift.

The effects of forced activity on circulating catecholamines and pH and water content of erythrocytes in the toad.

In vivo experiments were carried out to determine the effect of forced activity on circulating catecholamine levels, haematocrit, and the pH and water content of erythrocytes in the toad, Bufo marinus. In addition, the effect of the beta-adrenergic agonist isoproterenol on erythrocyte pH and water content was examined in vitro. Forced activity caused a significant decrease in both whole blood and erythrocyte pH, while haematocrit and circulating adrenaline and noradrenaline levels increased. Erythrocyte water content did not change following forced activity. Addition of isoproterenol to toad blood in vitro had no effect on either erythrocyte pH or water content. The apparent absence of beta-adrenergic effects on erythrocyte pH and water content in the toad is in sharp contrast to the response of teleost fish erythrocytes to beta-adrenergic stimulation. The significance of these differences is discussed.

Erythrocyte water content in spontaneously hypertensive rats and DOCA-salt hypertensive rats.

Intra-erythrocyte water, sodium and potassium contents were measured in spontaneously hypertensive rats (SHR) and deoxycorticosterone acetate (DOCA)-salt rats. In 12 week old SHR, the intra-erythrocyte water content was slightly but significantly lower than that in age-matched Wistar-Kyoto (WKY) rats. SHR also exhibited a significantly lower intra-erythrocyte potassium content, but sodium content tended to be elevated. Although sodium content was not correlated with the water content, potassium content was. In DOCA-salt hypertensive rats, the intra-erythrocyte sodium content was higher than that in age-matched normotensive Sprague-Dawley rats by about 33%, but the water and potassium contents were similar. There were no significant correlations between these parameters. These findings provide no evidence of water retention in erythrocytes from DOCA-salt rat or SHR even though intra-erythrocyte sodium content was increased.

Decreased water and potassium content in erythrocytes in essential hypertension.

The water content in erythrocytes of subjects with borderline or established essential hypertension was measured by using gas-liquid chromatography and was found to be lower than that in normotensive controls (p less than 0.01). The water content in erythrocytes of normal controls (n = 14), borderline hypertensive subjects (n = 18), and established essential hypertensive subjects (n = 23) was (mean +/- SE) 71.0 +/- 0.2%, 69.9 +/- 0.2%, and 69.3 +/- 0.1% (vol/vol), respectively. A definite negative correlation was found between water content of erythrocytes and mean arterial pressure in normotensive and hypertensive subjects (n = 60, r = -0.59, p less than 0.001). Although there was no statistically significant between-group difference in the sodium content, the potassium content of erythrocytes from subjects with essential hypertension was significantly lower than that of normotensive controls (0.205 +/- 0.003 vs 0.222 +/- 0.004 mumol/mg dry red blood cells; p less than 0.01). There was no between-group correlation of sodium and water content in erythrocytes, but the potassium content correlated with the water content (n = 46, r = 0.49, p less than 0.001).

Dialysis Induced Alteration in Erythrocyte Water Content Arid Volume

Dialysis Induced Alteration in Erythrocyte Water Content Arid Volume

Intraerythrocyte and plasma osmolality during graded exercise in humans.

The purpose of this study was to measure intraerythrocyte and plasma osmolality during graded exercise in humans. Eight volunteers performed a maximal exercise test on a cycle ergometer. Mean corpuscular volume, mean corpuscular hemoglobin concentration, and erythrocyte water content were not significantly (P less than 0.05) affected by the exercise bout in spite of a significant mean increase of 6.7% in plasma osmolality. Interestingly, intraerythrocyte osmolality also increased significantly during the exercise bout, paralleling the response seen in the plasma. In fact, plasma osmolality and intraerythrocyte osmolality demonstrated a significant linear relationship (r = 0.91). These data suggest that during exercise the human erythrocyte has the ability to increase its osmolality in vivo to match that of the plasma. Therefore, this mechanism allows for erythrocyte volume to remain relatively unchanged during exercise despite a significant increase in plasma osmolality.

Microwave dielectric properties of normal and homozygous beta-thalassemic erythrocytes

Recently, the dielectric properties of haemoglobin's suspending medium inside human erythrocytes have been studied in the frequency range from 0.1 to 250 MHz (Jenin and Schwan Biophys. J., vol.30, p.235, 1980). It was found that in this frequency range, the erythrocyte water content exhibits rotational mobilities similar to those in pure liquid and the interior of erythrocytes has electrical properties consistent with those of a standard haemoglobin solution. In particular, dielectric and conductometric measurements have shown no evidence of an interaction between the cell membrane and the adjacent water. To verify these conclusions by direct observations, the authors present measurements on the dielectric properties of erythrocyte suspensions, carried out at a frequency of 10.0 GHz in the temperature interval from 5 to 45 degrees C. They also present a comparative analysis between the dielectric properties of homozygous beta -thalassemic red blood cells and normal cells.

Hydration of sickle cells using the sodium ionophore Monensin. A model for therapy.

Mean cell hemoglobin concentration (MCHC) is thought to have an important influence in sickle cell disease, both through the strong dependence of sickling rates on hemoglobin S concentration, and through the profoundly limiting effect of high MCHC on the rheologic competence of oxygenated, irreversibly sickled cells (ISC). Recent studies have tested the ability of antidiuretic hormone to reduce sickle cell MCHC by reducing plasma sodium (Na) and osmolality. An alternative means of reducing MCHC is to elevate intracellular cation content, rather than to depress extracellular cation concentration. In an effort to do this, we have treated sickle cells with Monensin, an antibiotic that selectively enhances membrane Na permeability. At submicromolar concentrations, Monensin substantially reduced the MCHC of whole sickle blood and isolated ISC, causing an improvement in cell deformability. Monensin's effectiveness in producing a controlled increase in erythrocyte water content suggests that agents that selectively increase membrane Na permeability could be therapeutically useful.

Effect of lead in vitro on water metabolism and osmotic fragility of human erythrocytes.

The addition of lead to normal human blood was previously found to cause a decrease in erythrocyte osmotic fragility in vitro. The mechanism of the decreased osmotic fragility caused by lead has not been completely clarified, but the following hypothesis has been proposed. Lead causes a leakage of water from erythrocytes, thus more water can enter the cell before haemolysis occurs. There has been no report, however, of the direct measurement of the intracellular water content of erythrocytes treated with lead. This study has tried to clarify the relation between intracellular water and the osmotic fragility of lead-treated erythrocytes in vitro. The results showed that 0.05 microM/ml of lead decreased the osmotic fragility, the intracellular water content, and intracellular potassium and mean corpuscular volume, increased the plasma water content and trapped water content, and contracted the erythrocyte shape. These changes corresponded well with each other, and close coincidence of the osmotic fragility and the intracellular water content was also observed.

Changes in Leucocyte and Erythrocyte Water Content in Diabetic Coma

Conference Abstract| February 01 1982 Changes in Leucocyte and Erythrocyte Water Content in Diabetic Coma G. E. Levin; G. E. Levin 1St. George's Hospital, London Search for other works by this author on: This Site PubMed Google Scholar H. M. Mather; H. M. Mather 1St. George's Hospital, London Search for other works by this author on: This Site PubMed Google Scholar J.P. Monson; J.P. Monson 1St. George's Hospital, London Search for other works by this author on: This Site PubMed Google Scholar N. Finer; N. Finer 1St. George's Hospital, London Search for other works by this author on: This Site PubMed Google Scholar Susan Ell; Susan Ell 1St. George's Hospital, London Search for other works by this author on: This Site PubMed Google Scholar T.R.E. Pilkington T.R.E. Pilkington 1St. George's Hospital, London Search for other works by this author on: This Site PubMed Google Scholar Clin Sci (Lond) (1982) 62 (2): 35P. https://doi.org/10.1042/cs062035Pa Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Cite Icon Cite Get Permissions Citation G. E. Levin, H. M. Mather, J.P. Monson, N. Finer, Susan Ell, T.R.E. Pilkington; Changes in Leucocyte and Erythrocyte Water Content in Diabetic Coma. Clin Sci (Lond) 1 February 1982; 62 (2): 35P. doi: https://doi.org/10.1042/cs062035Pa Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentAll JournalsClinical Science Search Advanced Search This content is only available as a PDF. © 1982 The Biochemical Society and the Medical Research Society1982 Article PDF first page preview Close Modal You do not currently have access to this content.

The effect of lead on intracellular water content of human red blood cells. Part 1. An experiment in vitro (author's transl)

We observed in vitro experiment that lead increased osmotic resistance of normal human erythrocytes and decreased mean corpuscular volume and intracellular potassium. Though the mechanism of the increased osmotic resistance of erythrocytes caused by lead has not yet been completely clarified, the following hypothesis could be accepted. Lead causes leakage of water from erythrocytes, which means that more water can enter the cell before hemolysis occurs. But there has been no report of direct measurement of the intracellular water content of erythrocytes treated with lead. This paper tried to clarify the relationship between intracellular water and osmotic resistance of lead treated erythrocytes in vitro experiment. The results were: 0.05 mumol/ml of lead increases osmotic resistance, trapped water content and plasma water content of normal human blood and decreases intracellular water content after incubation for 2 hours at 37 degrees C.

Membrane defect affecting water permeability in human epilepsy.

McQUARRIE wrote that a disturbance in water balance perhaps affecting the central nervous system more specifically seems to be closely identified with the aetiology of epilepsy1. McQuarrie and Teglbjaerg2 studied water balance in relation to seizure frequency, establishing the ictogenic effect of excessive water ingestion, and the therapeutic value of dehydration. Schneider3 has reported that exacerbation of petit mal in children and adults is associated with reduction in urinary volume, and that clinical remission coincidences with an increase in water excretion. Reynolds4 has demonstrated disturbances in the whole body distribution of water in epilepsy, with a magnitude proportional to the frequency of attacks, concluding that the changes in body water and sodium are linked in some way to the aetiology of the disease. Wender and Strzyzewski5 have shown that water loading in epileptics produces seizures only in cases where there is also a marked increase in the water content of erythrocytes. There is thus abundant evidence linking epilepsy with water metabolism. Furthermore, diuretics, such as acetazolamid, are used in the therapy of epilepsies6. But the mechanism of the disturbance of water metabolism at the subcellular and molecular level has not been considered. We report here an investigation of water diffusion through erythrocyte membranes in epileptic children, made using a nuclear magnetic resonance (NMR) technique7. We found an abnormally low permeability in membranes from epileptics and suggest that a generalised membrane defect affecting water permeability is responsible for the disturbances of water metabolism in human epilepsy.