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1.
The loss of deformability observed in erythrocytes stored as whole blood for 36 days (ACD-AG) or as buffy-coat free erythrocyte concentrate (EK) was characterized by measuring their filterability. During the first 3 weeks the index of filterability for ACD-AG erythrocytes increased only slightly and rose to about 140% of its initial value on the 36th day. In contrast, a heavy loss of deformability (increase of the filterability index to more than 600%) was detected for erythrocytes from EK, which, from a rheological point of view, is apt to raise doubts of using this stored blood. An incubation of 1 hour at 37 degrees C in fresh plasma did not result in improving the deformability. A cell volume loss of more than 20% connected with an increase of the inner viscosity to more than 400% was found to be the cause of this decrease of deformability. These rheological differences are also reflected in the 24 hours in vivo survival rate (SR), if the "early loss" of damaged erythrocytes immediately after transfusion is taken into account. Whereas the SR values of 80% for whole blood erythrocytes do not change significantly, the SR values for EK values can be found to reach 54% approximately.  相似文献   

2.
The deformability changes of erythrocytes during 35 days of storage in different resuspension media were characterized by a filtration procedure. The filterability of erythrocytes stored in CDS-AG medium decreased drastically, whereas the filterability of erythrocytes stored in SAGM and SAGS medium decreased only slightly. The MCHC change of stored erythrocytes were discussed in relation to filterability effects.  相似文献   

3.
Red blood cell deformability has been studied by the initial filtration flow rate as a function of temperature. The well-known transition at 49-50 degrees C (probably due to spectrin denaturation) is shown. Another transition is demonstrated around 18 degrees C (the cell becomes stiffer below this temperature range). The erythrocyte membranes prepared by a mild dialysis technique have the same deformability as intact erythrocytes at room temperature; they also show the same low-temperature transition. No such transition has been found for hemoglobin solutions of viscosity 30 g X dl-1. It is interesting to compare these results with those obtained by other methods which measure the properties of natural or artificial lipid membranes and which also demonstrate a thermal transition at 15-20 degrees C. Therefore, the deformability of intact normal erythrocytes seems to depend mainly on the rheological properties of the membrane.  相似文献   

4.
Although many diseases of the heart and circulatory system have been linked with insufficient deformability and increased aggregability of red blood cells, there are only a few drugs which can modulate these biological functions of erythrocytes. Here, we show evidences that iloprost, stable prostacyclin analogue and SIN-1, active metabolite of molsidomine which spontaneously releases NO, may be sufficient pharmacological tools for modulating red blood cell deformability and aggregability. Deformability of red blood cells was measured by shear stress laser diffractometer (Rheodyn SSD) and expressed in percent of red blood cell deformability index (DI). MA-1 (Myrenne) erythrocyte aggregometer was used for photometric measurements of aggregability in arbitrary units (MEA) of mean extent of aggregation. Experiments were carried out on rats ex vivo and in vitro using whole rat blood or isolated erythrocytes. Ex vivo SIN-1 (infusion 2 mg/kg/min i.v.) and iloprost (bolus injection 10 microg/kg i.v.) significantly improved erythrocyte deformability and aggregability at 5-15 min after administration. L-NAME (10 mg/kg i.v.)- inhibitor of nitric oxide synthase, and aspirin (1 mg/kg i.v.) caused worsening of deformability of erythrocytes in experiments ex vivo. Studies in vitro also revealed improvement of red blood cell deformability and aggregability by SIN-1 (3 microM, 15 min incubation at 22 degrees C) or iloprost (1 microM, 15 min incubation at 22 degrees C) and this phenomenon appeared not only in whole blood but also in isolated red cells. It is concluded that NO- and prostacyclin-induced improvement of red blood cell deformability and aggregability results from direct action of these compounds on erythrocytes. NO-donors and iloprost could be useful in the treatment of disorders of blood fluidity.  相似文献   

5.
ACD blood with additions of adenine (A, 0.5 mM in blood), ademine + guanosine ((AG, 0.5 mM each) and adenine + guanosine + inosine (IAG, 0.5: 0.5: 18 mM) was stored for 6 weeks at 4 degrees C and the morphological changes in connection with the ATP content were observed. After a storage of 6 weeks 2--3% of the cells were present as diskocytes, 60% as echinocytes, and 40% as spherocytes. The delayed morphological alterations in the ACD-AG blood in comparison with ACD-A blood were also reflected by a higher ATP content of the ACD-AG blood during its storage. The alterations in the form of erythrocytes recorded in the morphological index Im (a subdivision was made according to 6 different stages of form) correlated with the ATP content. The coefficient of correlation amounted to r = 0.85. Thus, Im is a reliable criterium for evaluating possible storage damages of stored erythrocytes.  相似文献   

6.
In Plasmodium falciparum-parasitized erythrocytes, hemozoin (HZ) formation was accompanied by enhanced formation of 4-hydroxynonenal (HNE)-protein adducts on the cell surface, reaching in the HZ-rich schizont forms the 16.8-fold amount of control non-parasitized cells. The addition of 1-100 microM exogenous HNE to control non-parasitized cells generated HNE-adducts on surface proteins in amounts similar to those found in schizonts. Parasitized as well as HNE-treated non-parasitized erythrocytes showed decreased cell deformability (measured as decreased filterability through cylindrical-pore filters) related to the amount of HNE adducts. In vivo, the HZ-containing trophozoites and schizonts are phagocytic targets for monocytes/macrophages. The reduced deformability of circulating erythrocytes carrying HNE-adducts may increase their phagocytic elimination. Uncontrolled HNE production by parasitized erythrocytes may additionally modify non-parasitized bystander erythrocytes, induce their phagocytosis, and contribute to malarial anemia, which is predominantly due to the removal of large numbers of indirectly damaged non-parasitized erythrocytes.  相似文献   

7.
Deformability of bovine erythrocytes separated according to density (and age) was estimated by a modified Teitel's filterability test, the centrifugational test of Sirs, and viscosity measurements of cell suspensions. Both youngest and oldest erythrocytes were found to be less deformable than middle-aged cells, a result speaking against any chief role for deformability in the recognition of senescent erythrocytes and their removal from the circulation.  相似文献   

8.
Organic phosphates in human erythrocytes were selectively varied by incubating fresh human erythrocytes in phosphate-buffered saline containing inosine, pyruvate, adenine, and/or adenosine in various concentrations. The deformability of erythrocytes was measured at 24 degrees C with a rheoscope under shear stress of 8-82 dyn/cm2. (1) With increasing 2, 3-DPG (5 approximately 15 mM/l cells), undeformable erythrocytes increased due to the increased mean corpuscular hemoglobin concentration (MCHC). However, these cells became deformable, when the MCHC was reduced by suspending in hypotonic medium. (2) At the same MCHC, the deformability of 2, 3-DPG-enriched erythrocytes was still reduced, compared with that of control erythrocytes, probably due to altered membrane viscoelastic properties. (3) 2, 3-DPG-reduced erythrocytes (2.2 mM/l cells) was not altered in their deformability. (4) Deformability of 2, 3-DPG-enriched erythrocytes was not changed by lowering oxygen tension. (5) Deformability of erythrocytes was not affected by varying intracellular ATP in the range of 0.5 approximately 2.2 mM/l cells (ATP in control cells was 1 mM/l cells). (6) Increment of IMP (approximately 0.9 mM/l cells) and ITP (approximately 0.5 mM/l cells) did not alter the deformability of erythrocytes. (7) Interaction of intracellular organic phosphates with membrane proteins was discussed.  相似文献   

9.
T Koyama  T Araiso  J Nitta 《Biorheology》1987,24(3):311-317
The dynamics of membrane microstructure was studied as molecular motions of phospholipids for bullfrog erythrocyte ghosts by the DPH fluorescence depolarization technique with a nanosecond fluorometer. The bullfrog erythrocyte ghosts were obtained by hypotonic lysis and collagenase treatment. The constituents of membrane proteins were confirmed by the disk gel electrophoresis. The viscosity of erythrocyte membrane ghosts was estimated to be 3.3 +/- 1.0 at 10 degrees C, and 2.1 +/- 0.1 at 20 degrees C and 1.3 +/- 0.2 at 30 degrees C in the unit of poise and the wobbling angle of lipid molecule was 35 +/- 1, 41 +/- 1 and 43 +/- 1 degree at the respective temperatures on an average and +/- S.D. The viscosity is lower than that of human erythrocytes. The relatively low viscous phospholipid bilayer may be one of the factors for the deformability of bullfrog erythrocytes.  相似文献   

10.
Survival of Botrytis cinerea conidia was studied after storage without pretreatments at different temperatures (-80 degrees C, -20 degrees C, 4 degrees C and 21 degrees C). Germination tests performed during 3 years showed that viability at 21 degrees C was completely lost after 1 month. Conidia stored for 30 months at -80 degrees C, -20 degrees C and 4 degrees C were able to germinate, respectively, at 79%, 8% and 0.2%. Changes in adenylate level, energy charge and respiration (O(2) consumption) made on each set of conidia were correlated to the germination rate. The 30-month-old stored conidia showed differences in pathogenicity tests on apples. While the pathogenic aggressiveness of conidia stored at -80 degrees C was almost the same as for fresh conidia, it decreased with increasing temperature of storage. An ultrastructural study made on conidia stored for 30 months at -80 degrees C has shown the emergence of a new wall layer in a retraction zone of the cytoplasm by comparison to fresh conidia. However, the integrity of the cytoplasmic content was maintained. The effects of low temperature storage, maintenance of cell integrity and pathogenicity of conidia of B. cinerea are discussed.  相似文献   

11.
T Dobashi  H Goto  A Sakanishi  S Oka 《Biorheology》1987,24(2):153-162
We have measured volume fraction dependence of the sedimentation curve of swine erythrocytes in a physiological saline solution at 10 degrees C, 20 degrees C, 30 degrees C and 40 degrees C. The sedimentation curves were found to consist of initial constant velocity region and final plateau region at the lower temperatures of 10 degrees C and 20 degrees C, while modified S-shaped curves were observed at the higher temperatures of 30 degrees C and 40 degrees C. The volume fraction dependence of the initial slope v of the sedimentation curve was fitted well to the following exponential type equation at all the temperatures: v = vs,exp (1 - H)exp[-(BH + CH2)] where vs,exp is the velocity in infinite dilution corresponding to the Stokes velocity and H is the volume fraction of erythrocytes. The volume fraction dependence of the relative velocity v/vs,exp was in close agreement with a semi-empirical equation derived for slurrys in the field of chemical engineering at the lower temperatures, while a small deviation between the observed and calculated curves was found at the higher temperatures. The volume fraction dependence of v at 20 degrees C was also analyzed on a theory recently developed by Oka. The explicit functional form of the medium up-flow factor phi (H) and the deformability factor f in the theory were determined using the experimental data.  相似文献   

12.
When human erythrocytes were preincubated at 37-52 degrees C under atmospheric pressure before exposure to a pressure of 200 MPa at 37 degrees C, the value of hemolysis was constant (about 43%) up to 45 degrees C but became minimal at 49 degrees C. The results from anti-spectrin antibody-entrapped red ghosts, spectrin-free vesicles, and N-(1-pyrenyl)iodoacetamide-labeled ghosts suggest that the denaturation of spectrin is associated with such behavior of hemolysis at 49 degrees C. The vesicles released at 200 MPa by 49 degrees C-preincubated erythrocytes were smaller than those released by the treatment at 49 degrees C or 200 MPa alone. The size of vesicles released at 200 MPa was independent of preincubation temperature up to 45 degrees C, and the vesicles released from 49 degrees C-preincubated erythrocytes became smaller with increasing pressure up to 200 MPa. Thus, hemolysis and vesiculation under high pressure are greatly affected by the conformation of spectrin before compression. Since spectrin remains intact up to 45 degrees C, the compression of erythrocytes at 200 MPa induces structural changes of spectrin followed by the release of large vesicles and hemolysis. On the other hand, in erythrocytes that are undergoing vesiculation due to spectrin denaturation at 49 degrees C, compression produces smaller vesicles, so that the hemolysis is suppressed.  相似文献   

13.
Comprehensive research to quantify the deformability of erythrocytes in diabetic animals and humans has been lacking. The objective of this study was to compare the impairment of erythrocyte deformability in diabetic rats and patients by use of the same rheologic method. Deformability was investigated in streptozotocin-induced diabetic rats and diabetic patients, by using the highly sensitive and quantitative nickel-mesh-filtration technique. Erythrocyte filterability (whole-cell deformability) was defined as flow rate of hematocrit-adjusted erythrocyte suspension relative to that of saline (%). Hematological and biochemical data for diabetic rats did not differ from those for age-matched control rats except for hyperglycemia and malnutrition. Erythrocyte filterability for diabetic rats was significantly lower than that for control rats (69.4 ± 10.1%, n = 8, compared with 83.1 ± 4.2%, n = 8; p < 0.001). Likewise, erythrocyte filterability for diabetic patients was significantly impaired compared with that for controls (87.6 ± 3.4%, n = 174, compared with 88.6 ± 2.1%, n = 51; p = 0.046). Stepwise multiple regression analysis revealed that this impairment was mostly attributable to associated obesity (BMI, p = 0.029) and glycemic stress (HbA1c(JDS), p = 0.046). We therefore conclude that erythrocyte filterability is commonly impaired in diabetic rats and in humans. Moreover, metabolic risk accumulation further impairs erythrocyte filterability, resulting in derangement of the microcirculation.  相似文献   

14.
The ability of phospholipase C (Bacillus cereus) to lyse erythrocytes from human blood that had been stored under Transfusion Service conditions for up to 16 weeks has been examined. When incubated at 20 degrees C with enzyme (0.03 mg/ml, 55 units/ml) for up to 1 h fresh erythrocytes were not lysed. After about 4 weeks of storage a population of very readily lysed erythrocytes appeared. The morphological changes in erythrocytes from blood stored up to 16 weeks were examined by scanning electron microscopy. The proportion of very readily lysed erythrocytes correlated well with the proportion of spheroechinocytes I. This morphological form was shown to be preferentially removed by phospholipase C and before lysis a transient appearance of smooth spheres occurred. The decrease in blood ATP concentrations on storage was measured and found to correlate with the disappearance of discoid erythrocyte forms, but not directly with the increased susceptibility of the erythrocytes to lysis by the enzyme. However, erythrocytes of up to at least 15 weeks of age could be made less susceptible to lysis by pre-incubation in a medium designed to cause intracellular regeneration of ATP. During the lysis of spheroechinocytes I by electrophoretically pure recrystallized phospholipase C a rapid degradation of phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine + phosphatidylinositol) occurred together with a slower degradation of sphingomyelin.  相似文献   

15.
The functional state of erythrocytes from hen during their conservation with a preserving solution for 24 days at 4 degrees C, has been estimated by studying some biochemical and hemorheological parameters. Results show an initial phase in the preservation period (4-5 days) in which red blood cells maintain their values at levels similar to those at the beginning of the experience, except for osmotic resistance. Furthermore a progressive erythrocyte deformability loss, linked to ATP depletion (with rise in inorganic phosphate levels) as well as a gradually higher rate of hemolysis, were detected.  相似文献   

16.
P Snabre  H Baümler  P Mills 《Biorheology》1985,22(3):185-195
The aggregation behaviour of normal and heat treated (48.4 degrees C, 48.8 degrees C, 49.5 degrees C) red blood cells (RBCs) suspended in dextran-saline solutions (Dx 70, Dx 173) was investigated by a laser light reflectometric method over a wide range of bridging energies. The characteristic times of rouleau formation were found to be increased after RBC heat treatment. The disaggregation shear stress is not significantly different between normal RBCs and heat treated RBCs. The loss of cell deformability is nevertheless shown to improve slightly the dissociation efficiency of the flowing liquid in a shear flow resulting in a small reduction of the disaggregation shear rate after heat treatment. Heat treatment is also shown to alter the structure of RBC network at equilibrium. These results indicate that heat induced alterations of erythrocytes only affects the mechanical properties of the cell membrane without significant changes in the macromolecular bridging energy.  相似文献   

17.
The major feature of sickle cell anemia is the tendency of erythrocytes to sickle when exposed to decreased oxygen tension and to unsickle when reoxygenated. Irreversible sickle cells (ISCs) are sickle erythrocytes which retain bipolar elongated shapes despite reoxygenation. ISCs are believed to owe their biophysical abnormalities to acquired membrane alterations which decrease membrane deformability. While increased membrane surface viscosity has been measured in ISCs, the lateral dynamics of membrane lipids in these cells have not heretofore been examined. We have measured the lateral diffusion of the lipid analog 3,3'-dioctadecylindocyanine iodide (DiI) in the plasma membrane of intact normal erythrocytes, reversible sickle cells (RSCs), and irreversible sickle cells by fluorescence photobleaching recovery (FPR). The diffusion coefficients +/- standard errors of the mean of DiI in intact normal red blood cells (RBCs), RSCs, and ISCs at 37 degrees C are (8.06 +/- 0.29) X 10(-9) cm2 X s-1, (7.74 +/- 0.22) X 10(-9) cm2 X s-1, and (7.29 +/- 0.24) X 10(-9) cm2 X s-1, respectively. A similar decrease in the diffusion coefficient of DiI in the plasma membranes of the three cell types was observed at 4, 10, 17, 23, and 30 degrees C. ANOVA analysis of the changes in DiI diffusion showed significant differences between the RBC and ISC membranes at all temperatures examined. The characteristic breaks in Arrhenius plots of the diffusion coefficients for the RBCs, RSCs, and ISCs occurred at 20, 19, and 18.6 degrees C, respectively. Photobleaching recovery data were used to estimate (Boullier, J.A., Melnykovich, G. and Barisas, B.G. (1982) Biochim. Biophys. Acta 692, 278-286) the microviscosities of the plasma membranes of the three cell types at 25 degrees C. We find significant differences between our microviscosity values and those obtained in previous fluorescence depolarization studies. However, both methods indicate qualitatively similar differences in membrane microviscosity among the various cell types.  相似文献   

18.
Cellular deformability has been proposed in the past as a major determinant of lectin-mediated agglutination of cells. In this paper we have evaluated the correlation between deformability and Con A-agglutinability of human erythrocytes by subjecting them to agents that alter either one of the properties and evaluating the effect on the other property. The following results have been obtained: (i) Treatment with pronase or trypsin, which makes the Con A-nonagglutinable normal red cells highly agglutinable, has practically no effect on deformability; while neuraminidase treatment, with a similar effect on agglutinability, produces a small but statistically significant reduction in deformability. (ii) Diamide treatment, on the other hand, produces a drastic reduction in the deformability of pronase-treated erythrocytes but has no effect on the Con A-agglutinability of the cells. Dinitrophenol also reduces deformability but without altering the agglutinability, (iii) Chlorpromazine, at 2 x 10(-5) M, does not have any effect on the deformability of trypsinized cells, but increases the agglutinability substantially. When the Con A-agglutinability of the cells and their deformability after these treatments are compared, a correlation coefficient r = -0.353 (P greater than 0.1) is obtained. This indicates the lack of any direct correlation between the two parameters, and rules out any significant role of deformability in the determination of Con A-agglutinability of erythrocytes. The agglutination with the lectin is completely reversed by methyl alpha-D-mannoside, the specific inhibitory sugar for Con A, also ruling out any secondary role for deformability in the non-lectin-mediated stabilization of clumps. Upon incubation of normal erythrocytes with Con A. a dose-dependent decrease in deformability is observed, with the deformability index falling to almost 25% of the normal value with 500 microgram/ml Con A. This indicates that Con A binding to its receptor produces changes in the membrane probably by altering properties of the membrane skeleton.  相似文献   

19.
This study was designed to examine whether rat spermatozoa after freeze-drying and 1-year storage can participate in full-term development following intracytoplasmic sperm injection (ICSI). Cauda epididymal spermatozoa from Crlj:Wistar rats were frozen in liquid nitrogen (LN(2)), first dried for 14 hr at 0.37 hPa and then for 3 hr at 0.001 hPa. The dried spermatozoa were stored for 1 year in a desiccator at +25 degrees C, or in a refrigerator at +4 degrees C, or in LN(2) at -196 degrees C. Controls consisted of sperm that had only been frozen and stored in LN(2). After being stored, spermatozoa were sonicated to dissociate the sperm tail and were injected into oocytes from superovulated Slc:SD rats. The respective fertilization rates of oocytes injected with frozen sperm, or with freeze-dried sperm stored at +25, +4, and -196 degrees C were 79%, 75%, 70%, and 73%. However, the corresponding cleavage rates of injected oocytes were 63%, 1%, 38%, and 36%. After transfer of >80 zygotes of each group into recipients, the respective percentages of full-term normal offspring resulting from frozen sperm or from freeze-dried sperm stored at +25, +4, and -196 degrees C were 36%, 0%, 7%, and 14%. These results demonstrate that the storage temperature significantly influenced the likelihood of term development of rats produced by injection of oocytes with freeze-dried spermatozoa. Chromosomal analysis of the rat spermatozoa in the ICSI oocytes indicated that chromosomal aberration in freeze-dried spermatozoa stored at +25 degrees C (100%) occurred more frequently than in frozen control spermatozoa (41%) and freeze-dried spermatozoa stored at -196 degrees C (35%), and the frequency of chromosomal aberrations in freeze-dried spermatozoa stored at +4 degrees C (65%) was the intermediate. In conclusion, rat spermatozoa freeze-dried and stored at +4 degrees C for 1 year are capable of participating in full-term development after ICSI.  相似文献   

20.
1. In human erythrocytes the 2.3 DPG concentration was increased three to fourfold of the norm as IPP re-suspension by an incubation time of four hours at 37 degrees C or as ACD-AG blood was lowered below 20% of the norm respectively. After an autologous transfusion the 24 hours' surviving rate and the apparent half survival time of cells as well as the affinity of haemoglobin to oxygen in the total blood were measured. 2. The 24 hours' surviving rate for fresh erythrocytes with increased 2.3 DPG and ATP concentration amounts to 73% and the apparent half survival time amounts to 6 days. If erythrocytes are stored for four weeks as IPP resuspension at 4 degrees C, the 24 hours' surviving rate is 59%. Erythrocytes from fresh ACD-AG blood with lowered 2.3 DPG and a normal ATP concentration have a 24 hours' surviving time of 85% and an apparent half survival time of 24 days. 3. After autologous transfusion of 400 ml of erythrocytes with increased 2.3 DPG concentration the P50 value of the total blood will increase by 3 mm of Hg, after administering 400 ml of erythrocytes with lowered 2.3 DPG concentration it will fall by 1.8 mm of Hg. 4. The findings are discussed in connection with the significance of the changes of affinity of haemoglobin to oxygen produced by 2.3 DPG for the oxygen supply of tissues and under the aspect of using stored blood with increased 2.3 DPG concentration for practical purposes.  相似文献   

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