Hemorheological Parameters Research Articles

Relationship between haemorheological parameters and endothelial functional characteristics in patients with arterial hypertension

Relationship between haemorheological parameters and endothelial functional characteristics in patients with arterial hypertension

A Novel Integrative Processing Technology for the Preparation of Rehmanniae Radix Slices.

The traditional processing method for the slices preparation of Rehmanniae roots is time- and energy-consuming and is prone to result in loss of active components during twice water-treatment (once for wash and the other for softening) and drying steps. In this study, we firstly explored an integrative processing technique for Rehmanniae Radix by 2x3 factorial experiment based on the contents of catalpol and verbascoside as measured by HPLC. The potential differences between the traditional stepwise processing technique and the integrative processing technique for catalpol and verbascoside in the prepared slices were investigated. To further confirm the effectiveness of drugs using the integrative processing technique, some pharmacological variables, such as rectal temperature, hematologic parameters (RBC, HGB, HCT, and blood viscosity), and coagulation parameters (TT, APTT, PT and FIB), were detected in a blood-heat and hemorrhage syndrome rat model. Two-way ANOVA analysis showed that drying for 18 h at 50°C was considered as the best combination of process conditions. The mean catalpol and verbascoside contents in the integrative method-processed samples (4.30% and 0.33%, respectively) were higher than those in the traditional method-processed samples (2.61% and 0.21%, respectively). Significant increases in rectal temperature, and hematologic parameters, TT, APTT, and FIB, were observed in the model group rats, compared to the blank group animals (P<0.01). Both in the integrative groups and traditional groups, the extracts caused significant decreases in rectal temperature, RBC, HGB, and HCT with increased concentration compared to the model group animals. All coagulation parameters tested were shortened in model rats received two kind prepared slices. There were no significant therapeutic differences between the integrative and the traditional method-processed slices on the hemostasis and hemorheological parameters in this blood-heat and hemorrhage syndrome rat model, indicating that our integrative method may be a feasible technique for processing Rehmanniae Radix slices.

Dynamics of hemorheological parameters and their dependence on the helio geophysical environment in the modeled hypo-geomagnetic space as a prognostic model of bio-tropic consequences of global geomagnetic deprivation

Dynamics of hemorheological parameters and their dependence on the helio geophysical environment in the modeled hypo-geomagnetic space as a prognostic model of bio-tropic consequences of global geomagnetic deprivation

ВЛИЯНИЕ ГЕЛИОГЕОФИЗИЧЕСКИХ ФАКТОРОВ НА СВЕРТЫВАЮЩУЮ СИСТЕМУ КРОВИ БЕРЕМЕННЫХ С ПЛАЦЕНТАРНЫМИ НАРУШЕНИЯМИ

Geomagnetic storms are one of the natural abiotic risk factors for human health. The response of the organism to their impact depends on the individual adaptive abilities, which were formed during the evolution, but can change in the conditions of pathological processes. Evaluation of the effect of a weak magnetic storm (G4v (22 < Ar < 39 nTl) on hemorheological parameters of blood of pregnant women with placental insufficiency compared to healthy pregnant women showed an increase in platelet count (p = 0.05), fibrinogen content (p = 0.02), thrombocyte (p = 0.03), erythrocyte sedimentation rate (p = 0.004). At the same time, a decrease in the number of red blood cells (p = 0.04), hemoglobin concentration (p = 0.001), hematocrit value (p = 0.0009) was registered. We found a strong direct correlation between subpopulations of platelets, which are characterized by different functional activity. Heterogeneity of platelets, their multidirectional correlations with indicators of blood coagulation system of healthy pregnant women can be considered as a response to the change in the disturbance of the earth's magnetic field. For pregnant women with placental disorders, the magnetic storm was associated with increased activity of the blood coagulation system and a significant increase in its components in the blood of patients. Despite the fact that changes in the blood coagulation system occur from the beginning of pregnancy and are often adaptive, in pregnant women with placental disorders, the additional impact of a weak magnetic storm can be a risk of hemostasis disorders and the development of platelet thrombosis, timely diagnosis and therapy of which is important.

Dunye Guanxinning Improves Acute Myocardial Ischemia-Reperfusion Injury by Inhibiting Neutrophil Infiltration and Caspase-1 Activity.

Acute myocardial infarction is the most serious manifestation of cardiovascular disease, and it is a life-threatening condition. Dunye Guanxinning (DG) is a protective traditional Chinese patent herbal medicine with high clinical efficacy and suitable for the treatment of myocardial infarction. However, the mechanism through which it is beneficial is unclear. In this study, we hypothesized that DG improves acute myocardial ischemia-reperfusion injury by inhibiting neutrophil infiltration and caspase-1 activity. We found that DG administration decreased infarct size and cardiomyocyte apoptosis and improved left ventricular ejection fraction, fractional shortening, end-systolic volume index, end-systolic diameter, and carotid arterial blood flow output in rats. DG administration also improved hemorheological parameters, myocardial damage biomarkers, and oxidative stress indexes. The findings showed that DG administration inhibited neutrophil infiltration and reduced the serum interleukin-1 beta (IL-1β) level and myocardial IL-1β maturation. Moreover, DG administration inhibited caspase-1 activity and activated adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in rat hearts. These results suggested that DG administration inhibits inflammasome activity and IL-1β release through the AMPK pathway. Our findings support the clinical efficacy of DG and partially reveal its mechanism, which is beneficial for understanding the therapeutic effects of this protective traditional Chinese patent drug.

Higher Daily Physical Activity Level Is Associated with Lower RBC Aggregation in Carotid Artery Disease Patients at High Risk of Stroke.

Aim: Carotid artery disease (CAD) is an atherosclerotic inflammatory disease that affects the arterial wall, specifically at points of bifurcation where blood flow is disturbed. Abnormal blood rheology could participate in the pathophysiology of ischemic cardiovascular disease. Physical activity (PA) is known to improve blood rheology in several chronic disorders. This study aims to (i) compare the hemorheological profile of CAD patients and controls and (ii) investigate the associations between daily PA and hemorheological parameters in CAD patients.Methods: Blood viscosity, red blood cell (RBC) aggregation and RBC deformability were assessed in 80 patients (15 symptomatic and 65 asymptomatic) and 14 age-matched controls. Patients' PA levels were evaluated using questionnaires.Results: Symptomatic patients showed increased blood viscosity and RBC aggregation compared to healthy controls. RBC aggregation was significantly lower in the most physically active patients compared to the least physically active ones. Blood viscosity and RBC deformability did not vary according to physical activity level.Conclusions: Our results showed greater hemorheological abnormalities (blood hyper-viscosity and hyper-aggregation of red blood cells) in the most severe CAD patients, which could exacerbate the risk of stroke in patients with stenosis. As the most physically active patients had lower RBC aggregation than those who were less physically active, it is possible that regular PA may limit hemorheological alterations in CAD patients.

Effects of hydroxyurea on blood rheology in sickle cell anemia: A two-years follow-up study.

The aim of the present study was to test the effects of hydroxyurea (HU) therapy on clinical, hematological and hemorheological parameters in adult patients with sickle cell anemia (SCA). Hematological and hemorheological parameters were measured in 28 SCA patients before HU therapy (i.e., baseline) and at 6, 12 and 24 months of treatment. RBC deformability was determined by ektacytometry at 30 Pa. RBC aggregation properties were investigated by light-backscatter method. Blood viscosity was measured at 225 s-1 by a cone-plate viscometer. The rates of vaso-occlusive crises and acute chest syndrome were lower at 1 and 2 years of HU therapy compared to baseline. The proportion of patients with leg ulcers tended to decrease after 2 years of treatment. Hemoglobin oxygen saturation improved with HU therapy. HU therapy induced a decrease of platelet and white blood cell counts and a rise in fetal hemoglobin level and mean cell volume. While hemoglobin concentrations increased under HU, blood viscosity remained unchanged all along the study. RBC deformability increased over baseline values at 6 months of HU therapy and continued to rise until the end of the follow-up period. In conclusion, the improvement in RBC deformability probably compensates the increase of hemoglobin on blood viscosity and participates to the improvement of the clinical status of patients.

Therapeutic Efficacy of Methazolamide Against Intermittent Hypoxia-Induced Excessive Erythrocytosis in Rats

Zhang, Zhiqing, Zhonghai Xiao, Bingnan Deng, Xiaohua Liu, Wei Liu, Hongjing Nie, Xi Li, Zhaoli Chen, Danfeng Yang, and Ruifeng Duan. Therapeutic efficacy of methazolamide against intermittent hypoxia-induced excessive erythrocytosis in rats. High Alt Med Biol 19:69-80, 2018.-This study aimed to determine whether methazolamide is effective for the treatment of chronic mountain sickness. Forty-eight male Wistar rats were randomly divided into eight groups: normoxia control, hypoxia control, hypoxia + acetazolamide (30 mg·kg-1·d-1), and five hypoxia + methazolamide groups (5, 10, 30, 90, and 120 mg·kg-1·d-1). Excessive erythrocytosis was induced through 4 weeks of hypobaric hypoxia (8 hours O2 10%/16 hours O2 21%). Rats were then treated for 4 weeks, and their body weight was measured. Hematological, hemorheological, and biochemical parameters were analyzed. Renal hypoxia-inducible factor-1alpha (HIF-1α) and vascular endothelial growth factor (VEGF) levels were detected by immunohistochemistry. Proteomic analysis of plasma was conducted to determine the most differentially expressed proteins. Methazolamide with doses lower than 30 mg·kg-1·d-1 had no significant effects on body weight compared with the hypoxia control group (p > 0.05). Methazolamide dose-dependently reduced the hemoglobin concentration, hematocrit (Hct), and blood viscosity. Hct/blood viscosity, an oxygen delivery index, dose-dependently increased after methazolamide treatment. A methazolamide dose of 10 mg·kg-1·d-1 showed similar efficacy to an acetazolamide dose of 30 mg·kg-1·d-1 for all the above parameters. Plasma levels of low-density lipoprotein cholesterol, total cholesterol, creatinine, and hemoglobin increased substantially after long-term hypoxia, but decreased after methazolamide treatment. HIF-1α and VEGF both increased substantially after long-term hypoxia and decreased in the kidney after methazolamide treatment. The most differentially expressed protein was haptoglobin, an endogenous protective factor, which was depleted in rats with excessive erythrocytosis and increased substantially after methazolamide treatment. In summary, methazolamide exhibits dose-dependent efficacy for the treatment of excessive erythrocytosis induced by long-term hypoxia. It also has beneficial effects on oxygen transport and lipid metabolism, which are encouraging with regard to the development of methazolamide-based chronic mountain sickness therapies.

Effect of some newly synthesized xanthone and piperazine derivatives with cardiovascular activity on rheology of human erythrocytes in vitro.

This in vitro study was designed to examine the effect of some newly synthesized aminoalcanolic derivatives of xanthone (I, II) and aroxyalkyl derivatives of 2-methoxyphenylpiperazine (III, IV) having cardiovascular activity on the haemorheological parameters of RBCs from healthy individuals and patients with chronic venous disease. Additionally, the influence of compounds I-IV on some RBCs associated enzymes such as acetylcholinesterase (Ache), glucose-6-phosphate dehydrogenase (G6PD) and glutathione reductase (GR) as well as glutathione (GSH) content were determined in vitro in RBCs from healthy subjects. The study showed that compounds I, III and IV significantly increased RBCs deformability. Moreover, both xanthone derivatives reduced RBCs aggregation and diminished RBCs aggregates strength in all RBCs groups. Compounds II and III significantly improved Ache activity, whereas compounds I and II increased G6PD and GR activity and GSH level. In conclusion, compounds I, III and IV, which significantly improved RBCs deformability in vitro, may facilitate the passage of blood in the vascular system. Additionally, compounds I and II which inhibit RBCs aggregates formation in vitro may contribute to more rapid degradation of red blood cell aggregates in circulating blood.

Pentoxifylline treatment enhances antihypertensive activity of captopril through hemorheological improvement in spontaneously hypertensive rats during development of arterial hypertension

The rheological properties of blood play a significant role in the onset and progression of arterial hypertension. The aim of our work was to evaluate the effect of the angiotensin-converting enzyme inhibitor captopril (20 mg/kg/d), pentoxifylline (PTX; 100 mg/kg/d), and the combination of captopril + PTX (20 + 100 mg/kg/d) on the hemodynamic and hemorheological parameters in spontaneously hypertensive rats (SHRs) during the development of arterial hypertension. In the group of animals that received captopril, the mean arterial pressure (MAP) was significantly lower by 30% due to a decrease in cardiac output of 23% and in total peripheral resistance (TPR) of 26% compared with the control group, whereas blood viscosity did not change significantly. PTX-treated SHRs had significantly lower MAP and TPR (by 19% and 31%, respectively) and blood viscosity (by 4%–6%) and a higher erythrocyte deformability index (by 1.5%–2%) than the control group. In the group of animals that received captopril + PTX, MAP and TPR were significantly lower, by 41% and 46%, than those in the control group, and by 16% and 27% than those in the captopril group. The combination of the angiotensin-converting enzyme inhibitor captopril and the hemorheological agent PTX, affecting various systems that are involved in blood pressure regulation, exhibits synergism and prevents an increase in arterial blood pressure during the development of arterial hypertension in SHRs (ie, from 5 to 11 weeks of life).

Effects of pentoxifylline on hemodynamic, hemorheological, and microcirculatory parameters in young SHRs during arterial hypertension development

ABSTRACTThe most common form of hypertension in young adults is isolated diastolic hypertension. Diastolic arterial pressure is determined by the total peripheral resistance and depends on both vascular hindrance and blood viscosity. The aim of our work was to study the efficiency of pentoxifylline (PTX) in young spontaneously hypertensive rats (SHRs) during the development of arterial hypertension. The effects of a treatment course with PTX (100 mg/kg/day p.o. for 6 weeks, from 5 to 11 weeks old) on the mean, systolic, and diastolic blood pressure (BP); stroke volume; cardiac output; total peripheral resistance (TPR); whole blood viscosity (BV); plasma viscosity; hematocrit; RBC aggregation and deformability; local cerebral blood flow (lCBF); and microvascularization of the visual cortex were studied in SHRs in comparison with control SHRs and Wistar Kyoto rats. PTX-treated SHRs had significantly lower systolic, diastolic, and mean BP (by 24%, 26%, and 15%, respectively) and BV (by 5–9%) and a higher erythrocyte deformability index (by 1.5–2%), lCBF (by 42%), average diameter of capillaries (by 11%), density of the capillary network (by 23%), and percentage of capillaries with a diameter of 3–7 µm in comparison with control SHRs. In conclusion, PTX exerted positive effects on the hemodynamic, hemorheological, and microcirculatory parameters in SHRs during the development of arterial hypertension.

Meta-analysis on the randomized controlled trials of breviscapine injection plus conventional therapy for unstable angina pectoris

Objective To systematically evaluate the clinical effectiveness and safety of Breviscapine injection combined with conventional therapy in the treatment of unstable angina pectoris (UAP). Methods The literature were systematicly retrieved about the randomized controlled trials (RCTs) of Breviscapine injection for UAP. The Cochrane Risk of Bias Assessment Table was used to evaluate the methodological quality of the RCTs and then the data were extracted and meta-analysed by RevMan 5.3 software. Results A total of 15 RCTs with 1202 participants were included. In the meta-analysis, the combination of Breviscapine injection and conventional therapy in the treatment of UAP can achieve better angina pectoris curative effect (Z=7.74, P<0.01), the RR (95% CI) was 1.23 (1.17,1.30), and the electrocardiogram curative effect (Z=6.26, P<0.01), the RR (95% CI) was 1.32(1.21, 1.44). Furthermore, Breviscapine injection can improve hemorheologic parameters. And there was no major or serious adverse drug event. Conclusions The Breviscapine injection combined with conventional therapy shows good therapeutic effect on UAP. Key words: Angina, unstable; Randomized controlled trials; Meta-analysis; Breviscapine injection

Hemorheological parameters in patients with fibromyalgia syndrome.

To evaluate hemorheological parameters in patients with fibromyalgia syndrome (FMS) in order to elucidate the etiology of the disease. Twenty-three adult FMS patients and 20 healthy controls were enrolled in the study. Diabetics, hypertensives and those with any rheumatological disorder or use drugs or smoking cigarette were excluded from the study. Following parameters were analyzed in each subject; erythrocyte deformability, erythrocyte aggregation, plasma viscosity, complete blood count, fasting blood glucose, fibrinogen, albumin, globulin and lipid profile. Erythrocyte elongation indices indicating deformability of erythrocytes were higher in FMS patients (0.564±0.002 at 16.87 mPa and 0.605±0.002 at 30 mPa shear rate) than controls (0.558±0.001 at 16.87 mPa and 0.600±0.003 at 30 mPa shear rate). Erythrocyte aggregation speed was higher in FMS patients (2.1±0.1 s) than controls (2.3±0.2 s). Erythrocyte aggregation index was also higher in FMS patients (65.5±1.3) than controls (62.9±1.5). Erythrocyte aggregation amplitude and plasma viscosity values were similar in both groups (both p > 0.05). Among the complete blood count and biochemical parameters, only albumin levels were lower in the FM patients than controls (p < 0.05). Our results indicate higher erythrocyte deformability and quicker erythrocyte aggregation in FM patients.

Pravastatin improves postprandial endothelial dysfunction and hemorheological deterioration in patients with effort angina pectoris.

Postprandial hypertriglyceridemia and hyperglycemia may promote endothelial and hemorheological dysfunction. The present study investigated the effects of pravastatin on endothelial function and hemorheology in patients with stable angina pectoris (AP) before and after eating a test meal. We recruited 26 patients with stable AP who had impaired glucose tolerance and mild dyslipidemia and six healthy men as controls to assess endothelial function and hemorheological behavior. In each group, we measured forearm blood flow (FBF) during post-ischemic reactive hyperemia and obtained blood samples before and 2h after the test meal. Pravastatin 20mg/day was then commenced in the 26 AP patients. The above tests were repeated after 2 days and 6 months. Maximum FBF during hyperemia in the baseline fasting phase was significantly lower in the AP patients than in the controls (p < 0.05). Fasting and postprandial FBF during reactive hyperemia time-dependently improved after pravastatin treatment (p < 0.05 vs. baseline data for each phase). Pravastatin treatment for 6 months, but not for 2 days, inhibited leukocyte activation and improved hemorheological parameters. In conclusion, pravastatin treatment for 6 months improved fasting and postprandial endothelial and hemorheological dysfunction in AP patients.

Cerebral and muscle microvascular oxygenation in children with sickle cell disease: Influence of hematology, hemorheology and vasomotion

The present study investigated cerebral and muscle hemoglobin oxygen saturation (tissue oxygen index, TOI) in children with sickle cell anemia (SS), sickle cell hemoglobin C disease (SC) and healthy children (AA). TOI was measured by near-infrared spectroscopy (NIRS) and spectral analysis of the TOI variability was used to assess flowmotion and vasomotion. Arterial oxyhemoglobin saturation (SpO2), hemorheological and hematological parameters were also measured in SS and SC children. Both TOI were lower in SS compared to both AA and SC children, with SC exhibiting lower values than AA children. Cerebral vasomotion expressed in absolute values was enhanced in SS compared to AA and SC children. Muscle vasomotion did not differ between the three groups. Hematocrit, SpO2 and red blood cell deformability were positively associated with cerebral TOI in SS children. We demonstrated that 1) cerebral and muscle TOI were markedly decreased in SS children while the decrease of TOI was milder in SC children, 2) cerebral TOI level was associated with several biological markers in SS children only and 3) cerebral vasomotion was enhanced in SS, possibly to counterbalance the effects of chronic cerebral hypoxia.

The knockout of urea transporter-B improves the hemorheological properties oferythrocyte.

Urea transporter-B (UT-B), highly expressed in erythrocyte, confers specific permeability to urea, urea analogues and water. The purpose of this study was to determine the hemorheological properties of UT-B null erythrocyte using a series of biophysical techniques. The blood was taken from UT-B knockout and wild-type mice and the hemorheological parameters were measured. The UT-B inhibitor, PU-14, was used to treat the erythrocyte of wild-type mice in vitro and the deformability of the treated erythrocyte was analyzed. The results showed that UT-B knockout improves the hemorheological properties of erythrocyte, including increased erythrocyte deformation index, small deformation index, orientation index, low osmotic fragility and high electrophoretic rate. The UT-B inhibitor PU-14 had the similar effect as UT-B knockout on the deformation indices. The whole blood viscosity in UT-B knockout mice showed reduction trend as compared to wild-type mice. The data indicate that UT-B is involved in the regulation of hemorheology, which suggests that UT-B may be a potential therapeutic target for improving the hemorheology in some metabolic and hereditary diseases.

The relationship between hemorheological parameters and mortality in critically ill patients with and without sepsis.

The prognostic scoring systems for mortality of intensive care patients estimate clinical outcome using several physiological and biochemical parameters. In altered hemodynamic conditions of critically ill patients, hemorheological variables may play a significant role in appropriate tissue perfusion. We investigated if hemorheological parameters are altered in critical status and if they could be markers of mortality. 112 patients (67.8 ± 12 years, 58 males, 54 females) treated in intensive care unit with different non-surgical diseases were investigated. Routine laboratory parameters and prognostic scores were determined and hemorheological variables (hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability) were measured on the 1st and the 2nd day after admission. ICU scores predicted 35.2-41.3% mortality rate, real mortality in intensive care unit was 37.5%, while 30-day mortality was 46.6%. Whole blood viscosity (WBV) and red blood cell (RBC) deformability were lower, red blood cell aggregation was higher in septic than in nonseptic patients (p < 0.05). In septic patients calcium was increased, osmolality was decreased, while in nonseptic patients WBV and RBC aggregation were higher in nonsurvivors compared to survivors (p < 0.05). Worsening of RBC deformability from day 1 to day 2 predicted higher mortality (p < 0.05). Calcium and osmolality level were associated with outcome in sepsis. Whole blood viscosity, red blood cell aggregation and change in red blood cell deformability could predict mortality in nonseptic patients and they may add prognostic information over the ICU scores. Further investigations are needed to evaluate the benefit of our findings in clinical practice.

Altered microrheological parameters inRaynaud's phenomenon.

Raynaud's phenomenon is an episodic, painful attack of the acral parts caused by local diminished blood supply. The aim of our study was to examine hemorheological parameters, cold agglutinins, cryoglobulins and their relationship in patients suffering from Raynaud's phenomenon.Blood was taken from 74 patients (mean age: 48 years, female/male: 56/18). Cold agglutinins and cryoglobulins were determined. Hemorheological parameters were also measured such as hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability. Results were compared to a group of 58 healthy controls (mean age: 31.5 years, female/male: 24/34).Cold agglutinins were positive in 70%, cryoglobulins in 43% of patients. When compared to healthy controls, increased red blood cell aggregation (64.54 ± 8.93 vs. 61.11 ± 7.05) and decreased red blood cell deformability (0.669 ± 0.002 vs. 0.681 ± 0.001) was observed in Raynaud's patients (p < 0.05), but there were no differences in hematocrit (43.27% ± 3.85 vs. 44.10% ± 3.70), plasma (1.27 mPas ± 0.08 vs. 1.24 mPas ± 0.09) and whole blood viscosity (4.12 mPas ± 0.52 vs. 4.26 mPas ± 0.46). No differences were found between the hemorheological profile of cold agglutinin/cryoglobulin positive and negative patients. Also primary and secondary Raynaud's patients had similar rheological profile.Erythrocyte aggregation and deformability seems to be unfavorable in Raynaud's patients that can play a role in the disturbance of the microcirculation.

Alterations of erythrocyte rheology and cellular susceptibility in end stage renal disease: Effects of peritoneal dialysis.

In this study, we investigated the effects of peritoneal dialysis on hemorheological and hematological parameters and their relations with oxidant and antioxidant status of uremic patients. Hemorheological parameters (erythrocyte deformability, erythrocyte aggregation, osmotic deformability, blood and plasma viscosity) were measured in patients with renal insufficiency undergoing peritoneal dialysis (PD) and volunteers. Erythrocyte deformability, osmotic deformability and aggregation in both autologous plasma and 3% dextran 70 were measured by laser diffraction ektacytometry. Enzyme activities of glutathione peroxidase, superoxide dismutase and catalase were studied in erythrocytes; lipid peroxidation was studied by measuring the amount of malondialdehyde in both erythrocytes and plasma samples. Blood viscosity at native hematocrit was significantly lower in PD patients at all measured shear rates compared to controls, but it was high in PD patients at corrected (45%) hematocrit. Erythrocyte deformability did not show any difference between the two groups. Osmotic deformability was significantly lower in PD patients compared to controls. Aggregation index values were significantly high in PD patients in plasma Catalase and glutathione peroxidase activities in erythrocytes were decreased in PD patients whereas superoxide dismutase activity was increased compared to controls. Malondialdehyde was significantly increased in erythrocytes and plasma samples of PD patients which also shows correlations with aggregation parameters. It has been concluded that erythrocytes in PD patients are more prone to aggregation and this tendency could be influenced by lipid peroxidation activity in patient’s plasma. These results imply that uremic conditions, loss of plasma proteins and an increased risk of oxidative stress because of decreasing levels of antioxidant enzymes affect erythrocyte rheology during peritoneal dialysis. This level of distortion may have crucial effects, impairing the blood flow dynamics and causing inadequate microcirculatory perfusion.

Comparison of hemorheological changes in patients after acute coronary events, intervention and ambulatory rehabilitation.

During the past decades, our group have investigated the hemorheological parameters (HPs) of more than 1,000 patients with various forms of ischemic heart disease (IHD). Our data indicate that HPs are altered in patients with IHD and the extent of the alterations is in good correlation with the clinical severity of the disease. Our findings have also proven that HPs play a critical role in the pathogenesis of myocardial ischemia.The lack of regular exercise is an important cardiovascular risk factor. Regular physical activity - as part of the cardiovascular rehabilitation training program (CRP) - is recommended for the treatment of IHD and the prevention of first or further cardiovascular events. To estimate the beneficial hemorheological effects of CRP, compared to patients after a coronary event or intervention and not participating in CRP, the data of four of our prospective studies (three non-CRP and one CRP-participating) were evaluated.Hematocrit (Hct), plasma and whole blood viscosity (WBV), Hct/WBV ratio significantly (p < 0.05) increased in the non-CRP groups during the 6-12 months follow-up, while in the CRP group they significantly decreased (p < 0.05). Red blood cell aggregation decreased in a much greater manner in the CRP group.Our results indicate that CRP has beneficial hemorheological effects and is able to reverse the deterioration of HPs after coronary events or intervention.