Red Blood Cells Of Man Research Articles

Alterations in the Properties of Red Blood Cells in Men with Coronary Artery Diseases after Comprehensive Cardiac Rehabilitation.

Purpose Comprehensive cardiac rehabilitation (CCR) is a complex program aimed at improving the health status of patients with coronary artery disease (CAD), especially those who have been subjected to cardiac interventions (PCI and CABG).The aim of this study was to measure the changes in the properties of red blood cells (RBCs) in men with CAD after cardiac intervention and after participation in CCR program. Methods In this study, we have investigated the influence of the physical training-based CCR program in 12 men with CAD, after PCI or CABG. The characteristics of RBCs including the basic morphology of RBCs, the conformational state of RBC membrane protein and hemoglobin, acetylcholinesterase activity, membrane fluidity, the osmotic fragility, and thiol concentration in membrane and in hemolysate were measured. Ascorbate concentration and reduced glutathione were also determined. The analysis was performed in men, before and after participation in CCR. The properties of RBCs were observed in connection with the exercise test, and parameters were evaluated before, immediately after, and 1 hour after the exercise test. Results After CCR, a decrease in the mobility of erythrocyte membrane proteins was observed, which was accompanied by a decrease in lipid fluidity. In addition, immediately after the exercise test and 1 hour later, we measured a decrease in thiol level in hemolysate, but not in the plasma membrane. Unexpectedly, an increase in reduced glutathione concentration one hour after the exercise test after completing comprehensive cardiac rehabilitation was observed. Conclusion CCR in men with CAD after cardiac intervention is connected with decreased membrane fluidity and decreased membrane protein mobility, which indicates that reduction of oxidative changes in these components occurs.

More on the sodium saga.

The relationship between sodium (salt) intake and blood pressure has been convincingly established by epidemiological, observational, interventional, physiological, and some genetic evidence for some time. Yet the interaction remains the subject of passionate and heated debate. Even among those who are convinced of the salt–blood pressure interaction, some advocate a population-wide attempt to reduce dietary salt intake, arguing on the basis of epidemiological and interventional evidence, and others who suggest that such interventions should be targeted toward those most likely to benefit: the “salt-sensitive” subpopulation. Studies have characterized such subgroups on the basis of higher blood pressure, increased age or African-American ethnicity.1 The issue is rendered even more compelling by the findings that salt sensitivity can be identified among “normotensive” subjects (ie, those with blood pressure <140/90) as well as those with hypertension1 and the designation of those with blood pressure levels between 120 and 139 mm Hg systolic and 80 and 89 diastolic as prehypertensive2 and at increased risk for development of fixed hypertension and for cardiovascular events compared with those with lower blood pressure.3 Observational data have provided a starting point for the quantitative considerations of dietary salt intake. The most recent (1999–2000) NHANES survey provides an estimated dietary sodium intake based on food records, excluding discretionary sodium, of 135 to 204 mmol per day for men and 100 to 135 mmol per day for women in the United States.4 Questionnaires are acknowledged to underestimate actual intake, and urinary sodium excretion has been shown to provide a more accurate index of total sodium intake because it represents ≈93% of intake at steady-state conditions.5 A recent British survey reported that urinary sodium excretion averaged 187 mmol per day for men and 139 mmol per day for women.5 This was very similar to …

Membrane permeability and intracellular disposition of51Cr(VI) in human red blood cells†

Fast uptake kinetics of 51Cr(VI) into red blood cells (RBC) were studied. The uptake was determined as a process composed of two different first order processes with half lives of 23 sec and 10.4 min. Whereas the uptake of Cr(VI) in resuspended RBC (0.9% saline) was almost complete, in blood a portion of approximately 15% of the applied dose remained in plasma and did not penetrate into RBC, even after longer time periods. Over the concentration range studied (10 μM‐50mM), the fast initial uptake followed Michaelis‐Menten‐kinetics. The maximum capacity of this Cr(VI) transport into RBC of man was 3.1 × 108 ions × cell‐1 × min‐1. It is likely that Cr(VI) is transported under participation of “band‐3‐protein”;, a physiological anion carrier system of the RBC membrane. Intracellularly, chromium is almost quantitatively bound to hemoglobin, and thereby trapped for the cell's lifetime.

Sodium Pump Parameters of Red Blood Cells in Men, Women and Women Taking Oral Contraceptives

Three parameters of the sodium pump, the sodium efflux rate, the intracellular sodium content (Nai) and the number of sodium, potassium ATPase sites per red blood cell (sites/rbc) were measured simultaneously on erythrocytes from normal men and women and from women taking oral contraceptives. Significant (p less than 0.002) differences were obtained between normal men and women for sodium efflux (1.68 +/- 0.15 vs 1.52 +/- 0.12 mmoles/L rbc/hr). Among the three measured parameters, there was an inverse relationship (r = -0.74) between Nai and sites/rbc and a linear correlation (r = 0.89) between efflux per site and Nai. A positive correlation (r = 0.78) between the sites/rbc and a first-order rate constant for Na efflux/rbc suggests that one component of the rate constant is the number of sites/rbc. Values for a second-order rate constant, calculated from the assumption that efflux/rbc depends on both Nai and the number of sites/rbc, were similar for normal men and women but significantly (p less than 0.001) higher for women taking oral contraceptives.

Fast uptake kinetics in vitro of 51Cr (VI) by red blood cells of man and rat.

Fast transport kinetics of 51Cr (VI) into red blood cells (RBCs) in vitro were studied. No significant species differences were found between RBCs of man and rat. The uptake of 51Cr (VI) by RBCs in whole blood was composed of two different first order processes of different velocities (apparent t 1/2 of 22.7 s and 10.4 min for man and 6.9 s and 10.1 min for rat, respectively). However, even after longer time periods a fixed portion of approximately 15% of the administered dose remained in the plasma and did not penetrate into RBCs Over the entire concentration range studied (10 microM-50 mM), the fast initial uptake followed Michaelis-Menten kinetics. The maximal capacity of this Cr(VI) transport into RBCs of man and rat was 3.1 X 10(8) CrO4(2-) ions X cell-1 X min-1 and 2.5 X 10(8) CrO4(-2) ions X cell-1 X min-1, respectively. It is likely that Cr(VI) is transported into RBCs via a physiological anion carrier ("band-3-protein").

Quantitative local x-ray spectral microanalysis of single erythrocytes

Quantitative x-ray microanalysis was used to study the content of sodium, potassium, phosphorus and chlorine in single peripheral red blood cells of man. The method for sample preparation described permits its successful use under clinical and field conditions.

The activity of sorbitol dehydrogenase in some mammalian erythrocytes.

The activity of sorbitol dehydrogenase was found to be high in the red blood cells of man, dog, guinea-pig and mouse and comparatively lower in those of goat, sheep, rabbit, cat and rat.

Comparative studies on red blood cell glucose phosphorylating activities of mammals

1. 1. ATP- d-hexose-6-phosphotransferase activity was measured in red blood cells of man, rabbit, pig and cow. Mean values ranged from 0.60 to 1.06 units/g haemoglobin and no significant difference was obtained with different glucose concentrations. 2. 2. The characteristics of glucose phosphorylating activities in red blood cells of the species studied were similar. 3. 3. Chromatography on DEAE column revealed two different glucose phosphorylating activities in red cells of man, rabbit and pig, and only one in cow red cells. 4. 4.|The first hexokinase activity is the predominant form and is saturated with low glucose concentrations; the second is noticeably marked at high glucose concentrations.

Identification of plant sterols in plasma and red blood cells of man and experimental animals.

Direct gas liquid chromatography (GLC) of total plasma lipids showed small peaks (0.5-1.5% of total free sterol area) corresponding to free C28 and C29 sterols in ca. 50% of some 3,000 normal subjects and patients with hyperlipemia. Comparable proportions of similar peaks were present in the sterol fraction isolated from the red blood cells of many of these subjects. The maximum levels of these components in the plasma and red blood cells of domestic and laboratory animals were up to 10 times higher than those seen in man. Detailed gas chromatography/mass spectrometry analyses of the plasma lipids from a much more limited number of subjects and animals showed that the GLC peaks corresponding to the free C28 and C29 sterols were largely due to the plant sterols campesterol, stigmasterol, and beta-sitosterol. In all instances, variable amounts (0.05-0.2% of the total free sterol area) of 7-dehydrocholesterol, desmosterol, lanosterol, and cholesterol alpha-oxide were also detected. While the total content and composition of the plasma plant sterols appeared to vary greatly among the subjects, it never exceeded 2% of total sterol in the normal subjects and patients examined. There was no evidence for a significant increase in the plant sterol content of the plasma of patients with hypercholesterolemia or hypertriglyceridemia.

Occurrence and function of a high-Km hexokinase in immature red blood cells.

The formation of 14C02 from [1‐14C]glucose and [6‐14C]glucose by reticulocytes of rabbit and rat is dependent on the concentration of glucose over a wide range, indicating reactions preceding the formation of glucose‐6‐phosphate to be dependent on glucose concentration.In haemolysates of rabbit reticulocytes a high‐Km hexokinase was demonstrated by its kinetic properties. It corresponds to the glucokinase of liver. This enzyme does not occur in mature red blood cells of man and rabbit, nor in reticulocytes of newlyborns with erythro‐blastosis fetalis. The presence of glucokinase in reticulocytes introduces a metabolic path of glucose utilization which is not subject to regulation by the phosphofructokinase.

A comparative study on the phosphoglyceric acid cycle in mammalian erythrocytes

1. 1. The activities of the enzymes and intracellular concentrations of substrates and cofactors associated with phosphoglyceric acid metabolism in erythrocytes of nine mammals are reported. 2. 2. In every case 2,3-DPG phosphatase activity was lower than that of the other enzymes measured: glyceraldehyde phosphate dehydrogenase, diphosphoglycerate mutase, phosphoglycerate kinase and phosphoglycerate mutase. 3. 3. The red blood cells of man, rabbit, dolphin and pig contain high concentrations of 2,3-DPG and ATP whereas bovine, caprine and feline erythrocytes contain little of either compound. Equine erythrocytes contain large amounts of 2,3-DPG but little ATP. 4. 4. No 2,3-DPG and only very small amounts of diphosphoglyceric acid mutase was detected in the erythrocytes of the goat.

THE EFFECT OF DIET ON THE PHOSPHOLIPID COMPOSITION OF THE RED BLOOD CELLS OF MAN.

AbstractShort term (16 day) controlled fat (formula type diet) feeding to 10 healthy adult males led to no detectable change in the total amt or the relative proportions of the individual phospholipids of the red blood cells, although limited changes did occur in the fatty acids of certain of the phospholipids.The total phospholipid content of the red blood cells was 315ŷ10 mg/100 ml (average of 20 samples). Lecithin accounted for 34% of the total, with sphingomyelin, phosphatidyl ethanolamine and phosphatidyl serine representing 25, 25 and 16%, respectively. Approx 36% of the phosphatidyl ethanolamine, 4% of the phosphatidyl serine and 6% of the lecithin was present in the plasmalogen form.Each phospholipid class was found to have a distinctive fatty acid spectrum. The M ratio of saturated to unsaturated fatty acids in all three phosphoglycerides was nearly 1:1. Behenic, lignoceric and nervonic acids made up almost half of the sphingomyelin fatty acids, and the M ratio of saturated to unsaturated fatty acids in this lipid was 3:1.When compared with red cells from subjects consuming a diet with a high butter fat content, red cells from subjects on a diet rich in corn oil were found to contain higher levels of linoleic acid in the lecithin and phosphatidyl serine fractions, and lower levels of oleic acid in the lecithin fraction. No changes were observed in the fatty acids of the phosphatidyl ethanolamine and sphingomyelin fractions. It is probable that these alterations represent the result of highly specific exchanges with plasma fatty acids, and it is suggested that three levels of specificity are involved: class of phospholipid, type of fatty acid, and specific fatty acid.

The ribonucleic acid content of some mammalian erythrocytes.

RNA was determined in red blood cells of man and other mammals. Our report is based on 41 determinations. Red blood cells of rat showed the highest values in comparison with the blood cells of guinea pig, rabbit, horse and sheep which showed the lowest values, and man with intermediate ones. The method used was a combination of Schimidt and Thanhauser and Schneider extractions with the final reactions of pentose with the orcinol reagent colorimetrically measured.

Studies on hemagglutination and hemolysis by escherichia coli antisera.

A study on hemagglutination and hemolysis by Escherichia coli O111 and O55 (rabbit) antisera and on hemagglutination and hemolysis inhibition by E. coli O111 and O55 antigens revealed the following facts. 1. Red blood cells of man, dog, rabbit, guinea pig, sheep, rat, and chicken adsorb E. coli O111 and O55 antigens and thus become specifically agglutinable by the homologous E. coli antisera. 2. The adsorption of these E. coli antigens is a function of the concentration of the antigen, the time (from 5 minutes to 2 hours) of treatment of the red blood cells with the antigen, and the concentration of the red blood cells used. 3. Red blood cells of man and sheep adsorb simultaneously both antigens, as indicated by the fact that both antisera give agglutination of all red blood cells. Complete agglutination does not occur when a mixture of red blood cells treated separately with the two antigens is added to one or the other of the two antisera. 4. Treatment of red blood cells of man with one of the antigens does not block the adsorption of the second antigen. Human cells treated with either or both antigens are still agglutinated by the homologous blood group (A, B, and Rh)-specific antibodies. 5. In the presence of guinea pig complement, E. coli O111 and O55 antisera produce hemolysis of modified human red blood cells in titers of the same order of magnitude as those giving hemagglutination and bacterial agglutination. The same antisera produce hemolysis of sheep cells treated with the identical antigens in titers exceeding by far those giving agglutination of modified human or sheep red blood cells. 6. Both sediment and supernate of a boiled E. coli suspension are capable of modifying red blood cells for E. coli hemagglutination; in contrast, the supernate obtained from an unboiled suspension and then heated does not modify red blood cells for hemagglutination, although it contains the antigen which can specifically adsorb E. coli antibodies, as shown by means of the hemagglutination and hemolysis inhibition tests. 7. Both the unheated and the boiled suspensions of E. coli O111 and O55 inhibit hemagglutination and hemolysis specifically. 8. Rabbit red blood cells modified by either E. coli O111 or 055 antigens, upon intravenous injection into rabbits, engender specific E. coli antibodies. The significance of the results is discussed.

Demonstration of Escherichia coli 055 and 0111 antigens by means of hemagglutination test.

Summary(1) Boiled broth cultures and sterile Seitz filtrates thereof of Escherichia coli serogroups 055 and 0111 render red blood cells of man and rabbit specifically agglutinable by the homologous group-specific antisera. Unheated cultures, and nitrates are only slightly effective. Trypsinized red blood cells are somewhat better agglutinated than non-tryp-sinized cells. (2) The significance of the findings regarding the indirect bacterial hemagglutination test is discussed with particular reference to the phenomenon of bacterial inagglutinability.

The Plasma Potassium Level during Malaria Infection in Monkeys and Man

It is generally agreed that during malaria infections the rupture of the merozoites from the red cells releases into the blood a toxic substance, as yet unidentified, which is believed to be responsible for the pyrexia occurring at this period. Since the red blood cells of man, monkeys, and birds (the species known to be subject to malaria infections) contain twenty or more times as much potassium as their plasma, it is possible that this potassium might be released from the parasitized erythrocytes at sporulation in sufficient amounts to serve as the toxic substance. Pinelli (1) determined the serum potassium values in twenty cases of vivax malaria and reported values ranging from 27.0 to 40.6 mgm. per cent during fever, with a subsequent return to the values (about 20 mgm. per cent) found at the beginning of the chill. No explanation was offered for this potassium rise.

A Quantitative Analysis of Hemagglutination and Hemolysis

Summary and Conclusions The agglutination of red blood cells of man or dog with agglutinating serum on a hemacytometer slide permits fairly accurate quantitative studies of hemagglutination and hemolysis. Under the conditions of the experiments, the maximum agglutination of the red blood cells of dogs with agglutinating serum is reached in two to four hours, in man in about twenty-four hours at 18° to 20°C. In preparations with too few corpuscles in proportion to the serum, hemolysis is well under way before the maximum agglutination is reached, unless the temperature is very low. The same was true when too many corpuscles were present. This is at least one factor in the occurrence of “inhibition zones.” The higher the temperature, the more rapid the agglutination, and the more rapid hemolysis. The secondary separation of cells at the higher temperatures accounts for the impression of greater agglutination at lower temperatures. There is very little difference in the rate of agglutination when the corpuscles are suspended in saline-citrate solution or in serum. The latter delays hemolysis somewhat. There is practically no difference in the rate and completeness of agglutination if the corpuscle suspension is acid or alkaline. Hemolysis is more rapid in the former. With an acid serum the rate of agglutination was slightly slower than with the alkaline serum, but the maximum agglutination is the same. The processes of defibrination or of washing corpuscles until they are serum-free changes the composition of the red blood cells so that a greater proportion of cells do not agglutinate. Crenation delays agglutination, but the maximum amount is the same as in control preparations. The red cells which are most resistant to the serum hemolysis are those containing nuclei, reticulum, stippling or intracellular refractive granules (including Heintz bodies, Howell-Jolly bodies and others). Cup-shaped red blood corpuscles in the preparations studied are formed by the hemolysis of one of two red cells in apposition.