Disease relevance of Blood Viscosity

• This fall in blood-viscosity may be involved in the prophylactic effect of low-dose subcutaneous heparin in preventing venous thrombosis [1].
• Transgenic mice overexpressing erythropoietin adapt to excessive erythrocytosis by regulating blood viscosity [2].
• When used for treatment, high Epo plasma levels associated with increases in blood viscosity, however, may counteract beneficial effects of Epo in brain ischemia [3].
• Hypoalbuminemia causes high blood viscosity by increasing red cell lysophosphatidylcholine [4].
• The android obese women had a significantly higher hematocrit and red blood cell count and showed higher blood viscosity at both high and low shear rates than women with the gynoid obesity type [5].

High impact information on Blood Viscosity

• L-Arginine infusion significantly reduced systolic (11+/-3, mean+/-SE) and diastolic (8+/-2 mmHg, P < 0.001) blood pressure, platelet aggregation (20+/-4%), and blood viscosity (1.6+/-0.2 centipois, P < 0.01), and increased leg blood flow (97+/-16 ml/min), heart rate, and plasma catecholamine levels (P < 0.01) [6].
• However, the blood viscosity increased by up to 30% within 30 minutes after galactose injection, but not after glucose injection, and this significant difference in viscosities persisted for approximately 6 hours after glucose and galactose injections [7].
• There was a substantial reduction in exercise-induced cardiac ischaemia (eight patients had significant ST segment depression before erythropoietin, only one after 2 months' treatment, and none after 12 months' treatment), despite a significant rise in whole blood viscosity [8].
• Cerebral blood flow (CBF) was measured by the non-invasive xenon-133 technique in patients with increased blood viscosity as a result of paraproteinaemia or leukaemia [9].
• Reduction in blood viscosity by eicosapentaenoic acid [10].

Chemical compound and disease context of Blood Viscosity

• These results support the hypothesis that pentoxifylline reduces blood viscosity by improving red cell flexibility, and thereby enhances blood flow in patients with COAD [11].
• Polycythemia increases blood viscosity so that systemic O2 delivery (QO2) decreases and its regional distribution changes [12].
• Poloxamer 188 has been reported to inhibit thrombosis, decrease whole blood viscosity, and improve perfusion of damaged tissue [13].
• As part of a randomized, single-blind, comparative study evaluating the efficacy of lovastatin and bezafibrate retard in the treatment of primary hypercholesterolemia, hemorheologic parameters (whole blood viscosity, hematocrit, plasma viscosity, red blood cell aggregation and deformability, and fibrinogen) were studied in 35 patients [14].
• Elevated whole blood viscosity (WBV) has been independently correlated with increased carotid intima media thickness and major cardiovascular disease risk factors, including hypertension, smoking, diabetes, advanced age, elevated low density lipoprotein cholesterol, and decreased high density lipoprotein cholesterol [15].

Biological context of Blood Viscosity

• In controls, both sublingual glyceryl trinitrate and transdermal glyceryl trinitrate patches significantly reduced platelet aggregation (-38%; 95% CI, -49% to -27%) and blood viscosity (-8%; CI, -11% to -5%) and increased blood filterability (10%; CI, 7.0% to 13.1%) [16].
• There was a significant inverse correlation between hematocrit and CBF, presumably due to alterations in arterial oxygen content and blood viscosity [17].
• Elevated erythropoietin (EPO) plasma levels increase hematocrit and blood viscosity and may affect structure and function of the pulmonary circulation [18].
• Larger increases of Hct (>19% of baseline) led blood viscosity to increase >50%, overwhelming the NO effect through a significant viscosity-dependent increase in vascular resistance, causing MAP to rise above baseline values [19].
• The present study was thus designed to investigate EPO production during acute hypoxemia in a mouse model in which the oxygen-carrying capacity of blood, the plasma EPO level, the blood viscosity and the plasma EPO half-life are within normal values in spite of an intense stimulation of erythropoiesis [20].

Anatomical context of Blood Viscosity

• Increased whole blood viscosity during coronary artery bypass surgery. Studies to evaluate the effects of soluble fibrin and poloxamer 188 [21].
• Regression analysis was used to evaluate associations between fine particulate matter [aerodynamic diameter less than or equal to 2.5 microm (PM2.5)] and HRV, C-reactive protein (CRP), blood cell counts, and whole blood viscosity [22].
• CONCLUSION: Resveratrol can improve the microcirculation disorder of the lung by decreasing leukocyte-endothelial interaction, reducing blood viscosity, improving the decrease of blood flow, and stabilizing erythrocytes in SAP rats [23].
• The enhanced effect of splenic nerve stimulation and noradrenaline on splenic flow resistance is discussed in terms of the relative contributions of an increased smooth muscle response and increased blood viscosity [24].
• The model consists of resistance due to blood viscosity (R1), inertia of blood flow, compliances of the vessel (C1, C2), resistance of the peripheral arteries (R2) and the impedance of the of the femoral arteries (termination) [25].

Associations of Blood Viscosity with chemical compounds

• In both groups there was a significant decrease in the mean blood-viscosity 4 to 6 hours after the injection of heparin [1].
• OBJECTIVE: To examine the effects of cocaine in moderate doses on hematologic and hemostatic parameters that influence blood viscosity and thrombotic potential [26].
• Thus, sulodexide releases tissue plasminogen activator and decreases fibrinogen levels as well as HDL and total cholesterol levels and blood viscosity [27].
• Lack of dependence of cerebral blood flow on blood viscosity after blood exchange with a Newtonian O2 carrier [28].
• Plasma (but not dietary) vitamin C also showed inverse associations with both fibrinogen concentrations and blood viscosity [29].

Gene context of Blood Viscosity

• A defibrinogenic agent, batroxobin, which may diminish shear stress by reduction of blood viscosity, prevented iNOS induction as well as early aneurysmal changes [30].
• Among factors of blood viscosity, IGF-I exhibits a borderline correlation (p = 0.05) with "Tk" and the ratio IGF1/IGFBP3 which reflects free circulating IGF-I is correlated with red cell aggregability measured with the Myrenne "M" (r = 0.485, p = 0.014) and S60 (r = 0.396, p = 0.494) [31].
• Von Willebrand factor (vWF), Factor VIII, plasma viscosity, haematocrit, blood viscosity, tissue plasminogen activator (t-PA) and fibrin D-dimer were measured at rest and following stressful tasks in 238 middle-aged British civil servants [32].
• The risk of stroke was related to baseline levels of t-PA antigen (RR 1.87, 95% CI 1.04-3.34, P < or = 0.05) and whole blood viscosity (RR 1.33, 95% CI 1.07-1.65, P < or = 0.01) [33].
• CONCLUSION: RF has apparent protective effects on hepatic injury by increasing activity of GSH-Px and SOD, scavenging free radicals produced by CCl(4), reducing blood viscosity, and improving microcirculation and blood supply [34].

Analytical, diagnostic and therapeutic context of Blood Viscosity

• CONCLUSIONS: The increase in MCA blood flow velocity was associated with improved CO2 reactivity and reduced blood viscosity after defibrination [35].
• The results of these experiments appeared to indicate that cyclandelate, cyclandelate alcohol and flunarizine were approximately equipotent in maintaining RBC filtration and blood viscosity values [36].
• Niacin reduces blood viscosity through a variety of mechanisms, thus improving blood flow and perfusion through stenotic segments of the vasculature [37].
• Effect of oral administration of highly purified eicosapentaenoic acid on platelet function, blood viscosity and red cell deformability in healthy human subjects [38].
• The immediate effect of LDL apheresis was a fall in plasma fibrinogen by 50%, total and LDL cholesterol by 60%, plasma viscosity by 12% and whole blood viscosity by 17% [39].

References