Clinical Hemorheology and Microcirculation - Volume 3, issue 1

Authors: Steinhauer, H.B. | Lubrich, I. | Günter, B. | Schollmeyer, P.

Article Type: Research Article

Abstract: The behaviour of human platelets was studied by mechanical induced platelet aggregation under inhibition of different enzymes of the arachidonic acid metabolism. Platelet aggregation was followed by the release of thromboxane B2 (TXB2) and prostaglandin E2 (PGE2). The cyclooxygenase inhibitor indomethacin suppressed the generation of both arachidonic acid metabolites simultaneously with the platelet aggregation. Imidazole or OKY-1581 inhibited the aggregation induced synthesis of TXB2 in a dose dependent manner whereas the PGE2 synthesis increased. After selective inhibition of endogenous TXB2 generation by imidazole or OKY-158l no correlation was found between platelet aggregation and thromboxane synthesis in platelet rich plasma. These …results are in contrast to the general concept that platelet aggregation is mediated by TXA2. It is concluded that TXA2 is not essential for all sorts of platelet activation. Show more

Keywords: Thromboxane (TX), prostaglandin (PG), platelet agcregation (PAT III), indomethacin, imidazole, OKY-158l

DOI: 10.3233/CH-1983-3101

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 1-12, 1983

Authors: Neumann, V. | Cove, D.H. | Shapiro, L.M. | George, A.J. | Kenny, M.W. | Meakin, M. | Stuart, J.

Article Type: Research Article

Abstract: Twenty out-patients with steady-state diabetes mellitus were given placebo for 12 weeks followed by Ticlopidine for 12 weeks while studied serially for changes in platelet function and blood rheology. Ticlopidine rendered diabetic platelets refractory to adenosine diphosphate and caused a significant fall in plasma β -thromboglobulin. Significant improvements were also seen in viscosity (plasma and whole blood) and erythrocyte deformability (measured by filtration) but these changes were probably secondary to small reductions in plasma protein level and leucocyte count respectively during treatment. Patients with chronic vascular disease show a haematological stress syndrome response which includes hyperproteinaemia and a leucocytosis; drug-induced …modification of the stress response is an important factor influencing rheological studies. Show more

Keywords: Diabetes mellitus, Rheology

DOI: 10.3233/CH-1983-3102

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 13-21, 1983

Authors: Stuart, J. | Kenny, M.W. | Aukland, A. | George, A.J. | Neumann, V. | Shapiro, L.M. | Cove, D.H.

Article Type: Research Article

Abstract: A positive-pressure filtration technique, using 5 µm pore-size Nuclepore filters, was used to study erythrocyte deformability in 47 atherosclerotic patients (compared with 25 controls) and 55 diabetics (compared with 37 controls). The effects of hyperproteinaemia, which caused significant increases in plasma viscosity and whole-blood viscosity in the atherosclerotic patients, and which can also impair erythrocyte filtration, were eliminated by washing the erythrocytes. The leucocytosis of diabetes mellitus, which can also impair erythrocyte filtration, was corrected for by adjusting the filtration results to a standard leucocyte count of 7.5 × 109 /l. After elimination of these extrinsic variables, the filterability of …atherosclerotic and diabetic erythrocytes, from out-patients in the steady state, was not significantly different from that of control erythrocytes. Show more

Keywords: Atherosclerosis, Diabetes mellitus, Rheology

DOI: 10.3233/CH-1983-3103

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 23-30, 1983

Authors: Ernst, E.E. | Matrai, A. | Dormandy, J.A. | Flute, P.T.

Article Type: Research Article

Abstract: There is disagreement in the literature about the influence of fibrinogen on red cell deformability. Data on this problem is presented using six different experimental designs. They all suggest that fibrinogen has no effect on red cell deformability as measured by a filtration technique.

Keywords: fibrinogen, red cell deformability, red cell filterability, red cell aggregation

DOI: 10.3233/CH-1983-3104

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 31-36, 1983

Authors: Boudart, D. | Ozanne, P. | Lefebvre, J. | Lucas, J.C.

Article Type: Research Article

Abstract: This study was undertaken to assess the role of glycosylated hemoglobins (HbA1 ) in the reduced erythrocyte deformability of diabetic patients. Filtration tests were carried out on washed RBC suspensions and data show no correlation between the relative filtration time (RFT) and cell HbA1 concentration. Conversely, a strong correlation was found between RFT an cell HbA0 concentration. On the other hand, viscometric assays were performed on hemoglobin solutions after HbA1 a+b, HbA1 c and HbA0 were separated by chromatography. Glycosylated hemoglobin fractions show intrinsic viscosities about 2.5 fold that of non glycosylated fractions (HbA1 a+b : {η …} = 7.12 ml/g, HbA1 c : {η } = 7.63 ml/g, HbA0 : {η } = 3.07 ml/g). In conclusion, our data suggest that an increase in HbA1 induces an increase in RBC internal viscosity but seems to have no influence on RBC deformability when tested with a 5 µm filter. Show more

Keywords: Glycosylated hemoglobins, HbA1, diabetes mellitus, erythrocyte deformability, hemoglobin viscosity

DOI: 10.3233/CH-1983-3105

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 37-44, 1983

Authors: Garnier, M. | Hanss, M. | Paraf, A.

Article Type: Research Article

Abstract: The erythrocyte filterability of patients suffering from liver cirrhosis has been measured by a new technique. A significant decrease of the filterability has been demonstrated. The lipid composition of the ghosts has also been determined for the same patients. As compared to controls, the membrane cholesterol is increased, the sphingomyelin and the phosphoethanolamine are decreased. The cholesterol/phospholipid ratio is therefore significantly increased in the cirrhotic patients. A good correlation between the lower filterability and the higher cholesterol/phospholipid ratio is found, indicating that the abnormal rheological properties of the liver cirrhosis patient erythrocytes may have its origin in the membrane lipid …composition. Show more

Keywords: Erythrocyte deformability, liver cirrhosis, Erythrocyte membrane lipids

DOI: 10.3233/CH-1983-3106

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 45-52, 1983

Authors: Leterrier, F. | Saint-Blancard, J. | Stoltz, J.F.

Article Type: Review Article

Abstract: An enormous amount of work has been performed on the metabolic properties of the red blood cell during its storage in blood bank conditions, but the membrane structure changes (both at the molecular and at the macroscopic level) and the rheological perturbations of stored erythrocytes have been comparatively less well studied. In the last decade, the progress in our understanding of the organization and the properties of the red blood cell membrane has been considerable. It is thus interesting to review the work concerning the biophysical aspects of blood storage in the light of these recent findings. In a first …part, recent advances about the normal erythrocyte are summarized, emphasizing membrane structure and rheological properties. The reviewed literature is essentially limited to 1979–1981. The second part deals with the biological and rheological pertubations caused by storage of the blood in the liquid state. Aspects of storage in the frozen state have been excluded from this review. In the third and last part the possible causes of the observed modifications are analyzed from a molecular point a view, and the advantages of recent anticoagulant and preservative solutions are indicated. Show more

Keywords: blood conservation, erythrocyte membrane structure, erythrocyte shape, blood rheology

DOI: 10.3233/CH-1983-3107

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 53-95, 1983

Authors: Benner, Klaus-U.

Article Type: Abstract

DOI: 10.3233/CH-1983-3108

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 97-98, 1983

Article Type: Announcement

DOI: 10.3233/CH-1983-3109

Citation: Clinical Hemorheology and Microcirculation, vol. 3, no. 1, pp. 99-105, 1983