Determination of erythrocyte transit times through micropores. II-Influence of experimental and physicochemical factors

Koutsouris, D.; Guillet, R.; Wenby, R.B.; Meiselman, Herbert J.

doi:10.3233/bir-1988-25505

Cited by 21 publications

(12 citation statements)

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“…Blood cell deformability was measured with the Cell Transit Analyser (CTA), which determines the transit behaviour of individual cells traversing cylindrical pores in a special polycarbonate filter (Koutsouris et al, 1989;Fisher et al, 1992). CTA filtration studies were carried out at 25ЊC.…”

Section: Methodsmentioning

confidence: 99%

The anti‐neoplastic drug 5‐fluorouracil produces echinocytosis and affects blood rheology

Baerlocher¹,

Beer²,

Owen³

et al. 1997

Br J Haematol

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Summary. The anti-neoplastic agent 5-fluorouracil (5-FU) in high therapeutic doses can induce angina pectoris and myocardial infarction. The pathophysiological mechanism of this side-effect has not yet been elucidated. We analysed the influence of 5-FU on blood rheology in vitro. Whole blood, blood cell suspensions and plasma were incubated with increasing concentrations of 5-FU (final concentrations 0, 0 . 08, 0 . 4, 2, 10 and 25 mg/ml 5-FU) at 37ЊC. Erythrocyte morphology was analysed after fixation with glutaraldehyde. Viscosity was measured at high and low shear rates (94 and 0 . 1 s -1 ). Erythrocyte aggregation and the cell transit times of erythrocytes through 5 mm pores and polymorphonuclear leucocytes through 8 mm pores were determined. 5-FU induced a dose-dependent formation of echinocytes within minutes and was reversible upon removal of 5-FU, which reflected a preferential intercalation of the drug in the outer hemileaflet of the cell membrane. High shear blood viscosity was increased at the highest 5-FU concentration (148 Ϯ 12%), and at low shear rate a dose-dependent decrease was found (0 mg/ml: 100%, 0 . 08 mg/ml: 87 Ϯ 10%, 0 . 4 mg/ml: 80 Ϯ 19%, 2 mg/ml: 70 Ϯ 15%, 10 mg/ml: 40 Ϯ 19%, 25 mg/ml: 33 Ϯ 5%). Erythrocyte aggregation was decreased by the 5-FU-induced echinocytosis. The transit time of erythrocytes through narrow pores was increased in a dose-dependent manner by 5-FU, whereas the transit time of polymorphonuclear leucocytes was initially decreased at 10 mg/ml and returned to control after 60 min incubation. We conclude that 5-FU interacts with the cell membrane, induces echinocytosis and vesiculation and affects blood rheology in several ways which may contribute to cardiovascular complications.

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Section: Methodsmentioning

confidence: 99%

The anti‐neoplastic drug 5‐fluorouracil produces echinocytosis and affects blood rheology

Baerlocher¹,

Beer²,

Owen³

et al. 1997

Br J Haematol

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“…While the study of such subpopulations is possible using micropipette methods on individual cells (e.g., 3), this technique is extremely time consuming and yields relatively few observations. The concept of subpopulations of less deformable RBC is thus the rationale for the development of a new micropore filtration system, the Cell Transit Analyzer (CTA), which measures the rheological characteristics of a large number of individual erythrocytes and provides a frequency distribution of these properties [4,5]. Note that for RBC populations having a relatively small subpopulation of rigid cells, use of the pcrcentiles of the micropore transit time distribution, rather than only 0 1992 Wiley-Liss, Inc.…”

Section: Introductionmentioning

confidence: 99%

Influence of calcium permeabilization and membrane‐attached hemoglobin on erythrocyte deformability

1992

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The present study was designed to evaluate the influence of intracellular calcium [Ca]i regulated membrane attached hemoglobin (Hbm) on the deformability of human RBC and ghosts. [Ca]i of RBC was elevated via the ionophore A23187 (10 microM); the deformability of RBC and resealed ghosts was determined via measuring RBC and ghost transit times through 5 microns diameter pores with the Cell Transit Analyzer (CTA). Salient results included: (1) significantly increased RBC levels of Hbm following ionophore treatment; (2) elevated Hbm with increasing lysing medium calcium concentration (0-5 mM); (3) decreased deformability of both intact RBC and ghosts with increasing Hbm and significant (P less than 0.02 or better) linear relationships between Hbm and RBC or ghost transit times; and (4) an increased sensitivity to ionophore treatment/membrane attached hemoglobin for the higher percentiles of the CTA transit time distribution (i.e., for more rigid subpopulations). Our results thus indicate that calcium-induced interaction of hemoglobin with the RBC membrane produces cellular rheological changes; in addition, they demonstrate the usefulness of the CTA system in measuring both average RBC rheologic behavior and the distribution of cellular rheologic properties within an erythrocyte population.

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“…2627 Erythrocyte deformability was measured using a red blood cell filtration system, the Cell Transit Time Analyzer. 28 This instrument measures the individual transit times of 1,000 erythrocytes through cylindrical micropores 5 ^m in diameter by 15 /xm long by means of a computer-based conductometric system, then averages them to provide a mean value as well as various percentiles of the distribution. Red blood cell deformability and red blood cell velocity, the latter being inversely proportional to transit time, are highly correlated.…”

Section: Methodsmentioning

confidence: 99%

“…Red blood cell deformability and red blood cell velocity, the latter being inversely proportional to transit time, are highly correlated. 28 Fibrinogen was measured based on the turbidimetric rate of the formation of fibrin polymer (Du Pont ACA, Wilmington, Del.). Blood for coagulation assays was collected into tubes containing buffered sodium citrate (9 parts blood to 1 part sodium citrate); after centrifugation at 2,000g for 5 minutes, plasma was divided into multiple aliquots and frozen at -80°C until assayed.…”

Section: Methodsmentioning

confidence: 99%

Hematogenous factors and prediction of delayed ischemic deficit after subarachnoid hemorrhage.

Ameriso

Wong

Ishii

et al. 1992

Stroke

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Background and Purpose: Delayed ischemic deficits contribute to the high morbidity and mortality rates associated with subarachnoid hemorrhage. We evaluated the potential usefulness of measuring coagulation and hemorheological variables and cardiolipin antibodies for prediction of delayed ischemic deficit after subarachnoid hemorrhage.Methods: Consecutive patients with subarachnoid hemorrhage were studied. Coagulation and hemorheological variables and cardiolipin antibodies were measured on admission, within 7 days of subarachnoid hemorrhage. A subset of patients was studied on admission and at two subsequent occasions.Results: Sixty-nine patients were studied. Sixty-one of these were without clinical manifestations of vasospasm at admission, and 16 developed delayed ischemic deficit during their hospitalization. None of the laboratory variables measured were significantly different between patients with or without later development of delayed ischemic deficit. Elevation of the fibrin fragment D-dimer was found in the group of eight patients admitted with ischemic symptoms and in 49% (34 of 69) of all patients, but this was not associated with delayed ischemic deficit. Sixteen patients were studied on three occasions; this group showed a significant decrease in hematocrit, an increased white blood cell count, and no change in fibrinogen concentration.

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Determination of erythrocyte transit times through micropores. II-Influence of experimental and physicochemical factors

Cited by 21 publications

References 0 publications

The anti‐neoplastic drug 5‐fluorouracil produces echinocytosis and affects blood rheology

The anti‐neoplastic drug 5‐fluorouracil produces echinocytosis and affects blood rheology

Influence of calcium permeabilization and membrane‐attached hemoglobin on erythrocyte deformability

Hematogenous factors and prediction of delayed ischemic deficit after subarachnoid hemorrhage.

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