Clinical Hemorheology and Microcirculation - Volume 57, issue 4

Authors: Szentkereszty, Zsolt | Kotan, Robert | Kiss, Ferenc | Klarik, Zoltan | Posan, Janos | Furka, Istvan | Sapy, Peter | Miko, Iren | Peto, Katalin | Nemeth, Norbert

Article Type: Research Article

Abstract: Previously we have investigated the cerulein-induced acute pancreatitis and provided data on its micro-rheological impact in the rat. We hypothesized that non-steroid anti-inflammatory agent flunixin, the xanthine-derivate pentoxifylline and the low molecular weight heparin enoxaparin may have various beneficial effects improving microcirculatory and rheological parameters. In female rats, under general anesthesia, 10 μg/kg cerulein s.c. was administered and 2 hours afterwards microcirculation was tested by laser Doppler flowmetry on the tongue and after performing laparotomy on the small intestine, liver and pancreas prior to terminal blood sampling. From blood samples hematological parameters, blood pH, lactate concentration, erythrocyte deformability, osmoscan parameters …and erythrocyte aggregation were tested. Compared to normal control in acute pancreatitis group we found severe deterioration in tissue microcirculation together with impaired erythrocyte deformability and enhanced aggregation, accompanied by acidic pH and increasing lactate concentration. Improvement was found when using flunixin (s.c.), pentoxifylline (i.p.) or enoxaparin (s.c.). These drugs could partly improve the blood flux on the surface of the investigated organs, and the flunixin had the most expressed improving effects on micro-rheological parameters. Surprisingly, the improving effect of pentoxifylline on micro-rheological parameters was not obvious (red blood cell deformability did not improved better than in the other treated groups), however, microcirculatory parameters improved. Show more

Keywords: Red blood cell deformability, red blood cell aggregation, osmoscan, microcirculation, cerulein-induced acute pancreatitis, rat model, various drug therapy

DOI: 10.3233/CH-131674

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 303-314, 2014

Authors: Ercan, Meltem | Firtina, Sinem | Konukoglu, Dildar

Article Type: Research Article

Abstract: OBJECTIVE: In this study, we aimed to investigate the alterations in plasma viscosity and whether there was a relationship between plasma viscosity and endothelial dysfunction markers such as nitric oxide (NOx), asymmetric dimethylarginine (ADMA) and oxidized Low Density Lipoprotein (oxLDL) in dyslipidemic subjects. MATERIAL AND METHOD: 35 subjects with normolipidemia and 30 subjects with hyperlipidemia were involved in this study. Dyslipidemia was defined as total cholesterol levels ≥200 mg/dL and/or triglyceride level ≥150 mg/dL. Plasma total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, total protein, albumin levels and NOx were determined by enzymatic methods using commercial kits. …Plasma ADMA concentrations and serum levels of total oxLDL were determined by ELISA. Plasma viscosity was measured by Harkness capillary viscometer. RESULT: Plasma viscosity, ADMA and oxLDL values were significantly higher in subjects with dyslipidemia than in subjects with normolipidemia. Plasma NOx concentration was decreased in dyslipidemic subjects compared to the normo-lipidemic subjects. We found that fibrinogen had no effect upon plasma viscosity in selected patients with dyslipidemia. CONCLUSION: Our results demonstrated that the rheological impairment of dyslipidemic patients was related with endothelial dysfunction and this was a possible cause of both micro and macrovascular complications. Therefore, as plasma viscosity is also a sensitive parameter, it can add useful information about the diagnosis and treatment of various disorders, and it should be utilized more frequently in clinical medicine. Show more

Keywords: Atherosclerosis, plasma viscosity, shear stress, nitric oxide, asymmetric dimethylarginine, Oxidized LDL

DOI: 10.3233/CH-131706

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 315-323, 2014

Authors: Wang, B. | Li, B.W. | Li, H.W. | Li, A.L. | Yuan, X.C. | Wang, Q. | Xiu, R.J.

Article Type: Research Article

Abstract: Microvascular rarefaction with endothelial cells apoptosis is a common characteristic of various microvascular complications in the spontaneously hypertensive rat (SHR). Elevated levels of proteolytic (e.g. matrix metalloproteinase, MMPs) activity and apoptosis in aortic endothelial cells of SHR were found when compared to its normotensive control. However, the exact mechanisms of microvascular rarefaction and the role of MMPs in this process remain poorly understood. Besides cleavage of VEGFR2 via unbalanced MMPs, we hypothesize that selected cleavage of Beta-Catenin and VE-cadherin by MMPs could induce apoptosis of rat aortic endothelial cells (RAECs) and rarefaction. Primary RAECs were isolated, identified and used in …a in-vitro model. Transwell system was used to analyze the permeability of Wistar RAECs, SHR RAECs and SHR RAECs with pretreatment by doxycycline. Qualitative and semi-quantitative analysis of major endothelial adhesion molecules were detected by immunofluorescence technique and Western blot, respectively. MMP-2 activity of SHR RAECs was increased significantly and doxycycline (50 μM) effectively reduced the level of MMP-2 and hyper-permeability in SHR RAECs. SHR RAECs showed enhanced cleavage of VEGFR2, VE-cadherin and B-catenin, which could be prevented by doxycycline (50 μM). Doxycycline (50 μM) attenuated hyper-permeability via decreased MMP-2 by protecting VEGFR2, VE-cadherin, Beta-catenin from cleavage and inhibited the reduction of mitochondrial transmembrane potential (MTP), thus prevented mitochondria-mediated apoptotic signaling and capillary rarefaction in the SHR. It might be a novel insight into the mechanisms of SHR microvascular rarefaction that is independent of pressure but relevant to MMP-2. Show more

Keywords: MMP-2, microvascular rarefaction, SHR, aortic endothelial cells, hypermeability, Beta-catenin, VE-cadherin

DOI: 10.3233/CH-131713

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 325-338, 2014

Authors: Nemeth, Norbert | Kiss, Ferenc | Klarik, Zoltan | Toth, Eniko | Mester, Anita | Furka, Istvan | Miko, Iren

Article Type: Research Article

Abstract: We aimed to investigate hemodynamic, microcirculatory and hemorheological consequence of infrarenal or suprarenal aortic cross-clamping (IRAXC, SRAXC) in the rat. We hypothesized that the magnitude of the changes are different. Twenty-one male rats were randomized into Control, IRAXC or SRAXC groups. Under anesthesia the right carotid artery was cannulated for monitoring heart rate and mean arterial pressure, then median laparotomy was performed. In AXC groups the abdominal aorta and the caudal caval vein were atraumatically clamped for 60 minutes below or above the renal vessels. Before and just after the ischemia, in the 30th and 60th minutes of the reperfusion …besides hemodynamic test, laser Doppler flowmetry was used on the liver's, small-intestine's and the kidney's surface, then arterial (cannulated carotid artery) and venous (lateral tail vein) blood samples were taken for determining hematological, acid-base, erythrocytes' deformability, osmoscan and aggregation parameters. We found that when hemodynamic changes were prominent, microcirculatory or hemorheological parameters did not show such large differences. However, every parameter changed in various manners, showing more or less differences between IRAXC and SRAXC groups. Although the largest deviations were observable in SRAXC group, the acid-base and hemodynamic alterations were much more expressed than the micro-rheological ones. Further investigations of in vivo relations-correlations of changes in hemodynamic, microcirculatory, metabolic and hemorheological factors need further studies providing simultaneous monitoring possibilities. Show more

Keywords: Infrarenal or suprarenal aortic cross-clamping, ischemia-reperfusion, red blood cell aggregation, red blood cell deformability, microcirculation, hemodynamics, rat model

DOI: 10.3233/CH-131724

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 339-353, 2014

Authors: Ahmad, Basit | Glufke, Katharina | Grau, Marijke | Sandig, Dennis | Rockstroh, Jürgen | Vogel, Martin | Wasmuth, Jan-Christian | Bloch, Wilhelm | Brixius, Klara

Article Type: Research Article

Abstract: PURPOSE: This investigation assessed whether endurance training altered the red cell deformability (RCD) of male HIV patients. METHODS: Eight subjects (38 ± 9 years, BMI 23 ± 3.6 kg/m2 , highly active antiretroviral therapy) trained for a marathon run for the duration of one year. Each subject underwent an acute exercise test on a treadmill at the beginning of this study (baseline) and after four months of training. Blood samples were taken at rest (T0) and at the end (T1) of each exercise test, as well as before (T0) and after the marathon run (T1). RCD was measured using the …Laser Assisted Optical Rotational Cell Analyzer (LORCA), the maximal elongation index (EImax) and shear stress at half maximal deformation (SS 1/2 were determined using the Lineweaver Burke model. RESULTS: No changes were observed in RCD and SS 1/2 between T0 and T1 in all measurements. EImax significantly increased between T0 baseline and T0 after four months of training (P < 0.05). Measurements prior to the marathon run revealed significantly decreased EImax and SS 1/2 values (P < 0.05). CONCLUSIONS: The intensity of training in pathophysiological diseases like HIV is dependent for the alterations in RCD and possible improvements in microcirculation. Show more

Keywords: Red cell deformability, shear stress at half maximal deformation, HIV, endurance training, marathon run, cluster of differentiation 4

DOI: 10.3233/CH-131767

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 355-366, 2014

Authors: Maddison, Liivi | Riigor, Kairi Marie | Karjagin, Juri | Starkopf, Joel

Article Type: Research Article

Abstract: BACKGROUND: Microvascular alterations and intra-abdominal hypertension are both involved in development of organ failure. It is not known whether increased intra-abdominal pressure (IAP) is associated with microcirculatory perfusion derangements. HYPOTHESIS: Transient increase in IAP induced by pneumoperitoneum affects sublingual microcirculation. METHODS: 16 laparoscopic cholecystectomy patients were studied. Sidestream dark field (SDF) imaging was used to evaluate sublingual microcirculation. Microcirculatory videos were done before surgery, at least 15 minutes after initiation of pneumoperitoneum and 1 hour after the pneumoperitoneum. Microcirculation cut-off value for vessels was 20 μm. RESULTS: IAP was held at 12.6 (from 12 to 14) mmHg, mean (SD) duration …of pneumoperitoneum was 41 (14) minutes. At the baseline, mean total vascular density was 18.8 (2.6) and perfused vessel density 13.2 (2.9) per mm2 . Proportion of perfused vessels was 59 (11) % and microvascular flow index 2.2 (0.4). Median (IQR) heterogeneity index was 0.6 (0.4–0.9) and mean De Backer score 13.6 (1.5). Increase in IAP did not cause significant changes in sublingual microcirculatory parameters. CONCLUSIONS: Transiently increased IAP due to pneumoperitoneum does not affect sublingual microcirculatory blood flow and vessel density in patients undergoing laparoscopic surgery. However, the low proportion of perfused vessels indicates the prevalence of perioperative microcirculatory deficiency in these patients. Show more

Keywords: Microcirculation, intra-abdominal pressure, laparoscopic surgery, intra-abdominal hypertension, SDF imaging

DOI: 10.3233/CH-131791

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 367-374, 2014

Authors: Hsiu, Hsin | Hu, Hsiao-Feng | Wu, Guan-Shian | Hsiao, Fone-Ching

Article Type: Research Article

Abstract: MOTIVATIONS: The present study performed laser-Doppler flowmetry (LDF) measurements on the skin surface around the ankle with the aim of verifying if beat-to-beat analysis of the LDF waveform can help to discriminate the microcirculatory-blood-flow (MBF) characteristics between diabetic, prediabetic, and healthy subjects. METHODS: 84 subjects were assigned to three groups (diabetic, prediabetic, and normal) according to the results of oral glucose tolerance tests. Beat-to-beat analysis was performed on the pulsatile LDF waveform to obtain foot delay time (FDT), flow rise time (FRT), and the corresponding MBF-variability parameters (FDTCV and FRTCV). RESULTS: Relative to the control group, FDT and FRT were …significantly shorter in prediabetic subjects, FDT was significantly shorter in diabetic subjects, and FRTCV and FDTCV were significantly larger in prediabetic and diabetic subjects. There were no significant associations for FRT after adjustment for age and gender. CONCLUSION: The present results indicate that FRT may help to discriminate differences in the elastic properties of local vascular beds during diabetes or even during prediabetic stages. The proposed blood-filling-volume model can help to explain the underlying mechanism. The present findings may aid the noninvasive early detection of diabetes-associated vascular damage, and could be used in the development of home-care and telemedicine applications. Show more

Keywords: Diabetes, laser Doppler, beat-to-beat waveform, microcirculatory blood flow variability

DOI: 10.3233/CH-131794

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 375-384, 2014

Authors: Cagienard, F. | Schulzki, T. | Reinhart, W.H.

Article Type: Research Article

Abstract: Complications of cocaine administration are acute vascular occlusions such as myocardial infarction and stroke. We have studied the influence of cocaine on platelet function in vitro. For that purpose, citrated blood from healthy volunteers was incubated with cocaine concentrations of 0 (control), 10, 100, 1000, 2500, and 10'000 μmol/l plasma. Platelet aggregation was measured in whole blood under high shear flow conditions with a platelet function analyzer PFA-100 using either epinephrine (EPI) or ADP as a platelet activator, as well as in non-flowing blood measuring the change of impedance after the addition of either collagen or ADP (Chronolog-700 Aggregometer). In …addition, platelet aggregation was measured by the change in light transmission in platelet rich plasma containing the same cocaine concentrations (Chronolog-700). Platelet aggregation in flowing whole blood (PFA-100) was not affected by cocaine up to 1000 μmol/l, partially inhibited by 2500 μmol/l and completely inhibited by 10'000 μmol/l cocaine. In non-flowing blood, platelet aggregation was decreased already at cocaine concentrations of 1000 μmol/l with ADP and 2500 μmol/l with collagen as a platelet activator. In platelet-rich plasma, aggregation was partially inhibited by 1000 and 2500 μmol/l and completely inhibited by 10'000 μmol/l cocaine. We conclude that platelet aggregation is inhibited by cocaine in vitro. This occurs, however, at concentrations above those measurable in vivo. These observations make it very unlikely that a direct platelet activation plays a role in vascular events complicating cocaine consumption. Show more

Keywords: Cocaine, platelet aggregation

DOI: 10.3233/CH-131795

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 385-394, 2014

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 57, no. 4, pp. 395-400, 2014