BLOOD VISCOSITY, RED-CELL FLEXIBILITY, HÆMATOCRIT, AND PLASMA-FIBRINOGEN IN PATIENTS WITH ANGINA

The Lancet ◽  
1977 ◽  
Vol 310 (8045) ◽  
pp. 943-945 ◽  
Author(s):  
A.N. Nicolaides ◽  
Tikva Horbourne ◽  
Rosemary Bowers ◽  
P.H. Kidner ◽  
E.M. Besterman
Author(s):  
S Ono ◽  
S Ashida ◽  
Y Abiko

The hemorheological effect of ticlopidine was studied in rats ex vivo. Ticlopidine (30-300 mg/kg) was orally given to rats. Heparinized blood samples were taken from the carotid artery under pentobarbital anesthesia 3 hr after the drug administration for measurement of whole blood viscosity (ELD type cone-plate viscometer), micropore filtrability of red cells (Nuclepore membrane, 5 µm), erythrocyte sedimentation rate (ESR), hematocrit (Ht) and plasma fibrinogen. Red cell deformability was measured by counting the shear stressinduced cap-form cells under a scanning electronmicroscope. Mechanical flexibility of red cells was also studied by measuring hemolysis caused by turbulant flow.Ticlopidine treatment caused a significant decrease in whole blood viscosity (9.13 ± 0.15 and 6.17 ± 0.08 versus 9.80 ± 0.18 and 6.74 ± 0.09 Cp in control at 19.2 sec-1and 76.8 sec-1, respectively) and a significant increase in micropore filtrability of the red cells (0.54 ± 0.01 versus 0.40 ± 0.02 ml/min in control) without any changes in ESR, Ht and plasma fibrinogen. Ticlopidine also significantly stimulated the shear stress-induced shape change of the red cells to cap-form cells (12.08 ± 0.13 versus 8.66 ± 0.23 % in control) and prevented mechanical hemolysis caused by a turbulant flow (16.8 ± 1 . 6 versus 30.5 ± 2.5 % in control).In addition to the platelet aggregation inhibitory action the hemorheological action of this agent may be useful for improving microcirculation and protecting red cells from mechanical disruption by turbulant blood flow.Increase in the adenylate cyclase and Mg2+-activated adenosine triphosphatase activities in red cell membranes may be associated with the effect of ticlopidine to increase red cell deformability.


1979 ◽  
Author(s):  
G Cella ◽  
H de Haas ◽  
M Rampling ◽  
V Kakkar

Haemorrheological factors have been shown to be affected in many kings of vascular disease. The present study was undertaken to correlate these factors in normal subjects and patients suffering from peripheral arterial disease. Twenty-two patients were investigated; they had moderate or severe intermittent claudication, extent of disease being confirmed by aorto-arteriography and ankle-systolic pressure studies. Twenty-five controls with no symptoms or signs of arterial disease were selected with comparable age and sex distribution. Whole blood viscosity was measured at shear rates of 230 secs-1 and 23 secs-lat 37°c using a Wells Brookfield cone plate microvisco meter. Plasma viscosity was also measured in an identical manner. Erythrocyte flexibility was measured by centrifuge technique and fibrinogen concentration as well as haematocrit by standard techniques. The fibrinogen concentration appeared to be the only significant parameter; the mean concentration in patients with peripheral vascular disease of 463 ± 73mg/l00ml in the control group ( < 0.05). Although whole blood viscosity was high in patients, when corrected to a common haematocrit, there was no significant difference between patients and controls. The same megative correlation was found for plasma viscosity. The red cell flexibility was found to be increased in patients as compared to the control group, but this effect appeared to be simply proportional to the fibrinogen concentration.


1997 ◽  
Vol 147 (1) ◽  
pp. 49-54 ◽  
Author(s):  
Yoshiyasu Tsuda ◽  
Kiyoto Satoh ◽  
Masaya Kitadai ◽  
Tsutomu Takahashi

1979 ◽  
Vol 237 (4) ◽  
pp. H504-H513
Author(s):  
E. B. Reeve ◽  
A. Stephens ◽  
T. H. Carlson

Rabbits were bled 20 ml/kg body wt over approximately 1 h, and the changes in hematocrit, plasma total protein, and fibrinogen concentrations, red cell and plasma volumes, and masses of total protein and fibrinogen in the plasma during and for 4 days after the hemorrhage were monitored. Ten percent of plasma fibrinogen was transferred from the interstitial fluids during the hemorrhage, and total plasma fibrinogen was raised to 140% of initial levels by 1 day later. 131I-labeled fibrinogen was given intravenously 1 day before a 20 ml/kg hemorrhage, and simulation methods described in the APPENDIX were used to define changes in the posthemorrhage fractional rates: transcapillary transfer rate (j1), lymphatic return rate (j2), and catabolic rate of fibrinogen (j3): j1 was unchanged but j2 increased and j3 briefly declined. In the day after hemorrhage fibrinogen synthetic rate increased approximately threefold to restore plasma fibrinogen concentrations to initial levels, but then returned to normal or subnormal levels. The alterations in j2 and j3 save about 20% of the synthetic work that would otherwise be required to restore plasma fibrinogen levels to normal.


1983 ◽  
Vol 61 (10) ◽  
pp. 2344-2350 ◽  
Author(s):  
Mark S. Graham ◽  
Garth L. Fletcher

The effects of temperature, red cell concentration, and shear rate on the viscosity of blood from the winter flounder (Pseudopleuronectes americanus) were evaluated using a cone-plate viscometer. The viscosity of blood and plasma was shear rate dependent at all temperatures studied (−1 to 20 °C) with the highest values occurring at the lowest temperature and shear rate. At normal hematocrits (20%), plasma appeared to account for at least 50% of the total blood viscosity. The effects of hematocrit on viscosity were dependent on temperature. At higher temperatures (10–20 °C), increases in hematocrit resulted in a near-exponential increase in viscosity. At lower temperatures (5 °C) and shear rates (4.5 s−1) no significant increase in viscosity occurred between hematocrits of 11 and 43%. The influence of temperature and shear rate on blood viscosity suggest that winter flounder may have to contend with a fivefold increase in blood viscosity when acclimating from summer to winter water temperatures.


BMJ ◽  
1985 ◽  
Vol 290 (6461) ◽  
pp. 74-75 ◽  
Author(s):  
D P Mikhailidis ◽  
J Y Jeremy ◽  
M A Barradas ◽  
P Dandona ◽  
R A Hutton

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