-
[show abstract]
[hide abstract]
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.
Clinical hemorheology and microcirculation 04/2013; · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
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.
Clinical hemorheology and microcirculation 01/2013; · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Ischemia-reperfusion-caused hemorheological alterations have been widely studied but the effect of testicular ischemia-reperfusion has not so far. In this study 14 Sprague-Dawley rats were involved. In the ischemia-reperfusion group under general anaesthesia the left testis was explored by opening the scrotum then the deferent duct and vasculature were clamped for 30 minutes. Testicular microcirculation was monitored by laser Doppler flowmetry. The right testis was untouched. In the control group: only anaesthesia was induced. Blood sampling occurred before and after ischemia, at the 60th minute of reperfusion and on the 1st postoperative day for determining hematological parameters (microcell-counter), erythrocyte deformability (slit-flow ektacytometer) and erythrocyte aggregation (light-transmission aggregometer). After the last blood sampling, testicles were removed for histological examination. Hematological parameter changes reflected inflammatory response. Erythrocyte deformability showed a worsening already at the 60th minute of reperfusion compared to base and control values. By the 1st postoperative day further decrease was observed. Erythrocyte aggregation significantly enhanced with great magnitude versus base and control values (p < 0.001). However, conventional histological examinations did not show marked testicular injury. The experienced changes can attract attention to the testicular ischemia-reperfusion causing significant effects on hemorheological parameters, which can lead to further harmful microcirculatory consequences.
Clinical hemorheology and microcirculation 01/2013; · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Despite of the studies on widespread biological effects of irradiation, surprisingly only little number of papers can be found dealing with its in vivo hemorheological impact. Furthermore, other studies suggested that low-dose irradiation might differ from high-dose in more than linear ways. On Balb/c Jackson female adult mice hematological and hemorheological impacts of total body irradiation were investigated 1 hour following 0.002, 0.005, 0.01, 0.02, 0.05 and 0.1 Gy dose irradiation. In case of 0.01 Gy further groups were analyzed 30 minutes, 2, 4, 6, 24 and 48 h after irradiation. According to the results, it seems that the dose-dependent changes of blood micro-rheological parameters are not linear. The irradiation dose of 0.01 Gy acted as a point of 'inflexion', because by this dose we found the most expressed changes in hematological parameters, as well as in red blood cell aggregation, deformability and osmoscan data. The time-dependent changes showed progressive decrease in pH, rise in lactate concentration, further decrease in erythrocyte aggregation index and deformability, with moderate shifting of the optimal osmolarity point and modulation in membrane stability. As conclusion, low-dose total body irradiation may cause micro-rheological changes, being non-linearly correlated with the irradiation dose.
Clinical hemorheology and microcirculation 01/2013; · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Investigation of regional hemorheological properties are important in ischemia-reperfusion experimental surgical and microsurgical research models, however, the physiological arterio-venous as well as porto-caval differences in erythrocyte deformability and aggregation are still controversial. In this study, besides measuring blood pH, blood gases, lactate concentration and hematological parameters we determined erythrocyte deformability (rotational ektacytometer) together with osmoscan data as well as erythrocyte aggregation (light transmittance aggregometer) in blood samples taken from the portal vein, caudal caval vein and abdominal aorta of rats. Blood pH, partial blood gas pressures showed the anticipated physiological differences. Leukocyte count was lower in arterial blood; hematocrit, erythrocyte and platelet count was higher in systemic and portal venous blood. The lowest elongation index values were measured in arterial blood, the highest in venous and portal venous blood showed values in between. The osmoscan data did not show important differences. Erythrocyte aggregation M index 5 s showed the lowest values in arterial, higher in systemic venous and portal venous blood samples. M index 10 s showed significantly low values in systemic venous blood. M1 values were slightly higher in arterial blood compared to venous blood but the highest were in portal venous blood. Erythrocyte deformability and aggregation may show aorto-porto-caval differences in the rat. The appropriate control examinations thus are important in experimental surgical and microsurgical research models.
Clinical hemorheology and microcirculation 03/2012; · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Although microcirculatory disturbances play pivotal role in the pathomechanism of acute pancreatitis (AP), very few papers can be found which had been tested any of hemorheological parameters. The aim of our study was to analyze the hemorheological changes in cerulein-induced experimental acute pancreatitis in rat in two doses (5 and 10 μg/kg, s.c.). Male and female rats were subjected to Control group, or AP with 5 or 10 μg/kg cerulein groups. Blood samplings (lateral caudal vein) were completed before cerulein administration, and 1, 2 and 24 hours later. Hematological parameters, amylase activity, erythrocyte deformability (ektacytometry) and aggregation (light-transmission method) were tested. The presence of AP could be confirmed by amylase testing and histological examination. The earliest impairment of the red blood cell deformability could be observed 1 hour after cerulein administration in 10 μg/kg dosage. Female animals had the worst rheological results with high mortality. In conclusion, subcutaneously administrated cerulein in dosage of 5 and 10 μg/kg resulted in AP in rats, with significant changes in red blood cell deformability and alterations in erythrocyte aggregation. This model seems to be suitable for further comparative studies.
Clinical hemorheology and microcirculation 01/2012; 51(4):255-64. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Acid-base equilibrium and pH of blood have important clinical consequences in numerous diseases and pathophysiological conditions. The micro-rheological parameters of blood, such as red blood cell deformability and red blood cell aggregation are influenced by several metabolic factors, and provide information regarding inflammatory, septic and tissue or organ ischemia-reperfusion processes. Despite the anticipated logical relation of the blood acid-base condition, blood gas parameters and pH to red blood cell deformability and aggregation, controversial data can be found in the literature. Furthermore, related to ischemia-reperfusion hemorheological studies little is known about this issue. In this paper we aimed to thought-provokingly overview some aspect of acid-base changes, blood pH and hemorheological parameters, discussing certain results from ischemia-reperfusion experimental surgical models (local versus systemic changes), laboratory technical and experimental design protocols related to in vitro and in vivo studies.
Clinical hemorheology and microcirculation 01/2012; 51(1):43-50. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Growing number of clinical and experimental data reflect to the gender differences of hemorheological parameters. However, little is known about the potential hemorheological effect of gonadectomy and consequent changes in sex hormone concentration. Adult, same-aged male and female rats were involved in the study. In control male and female group no surgical intervention was performed. In gonadectomized (GoE) male and female groups bilateral orchidectomy or ovariectomy were completed. Body weight measurement and blood sampling were carried out in the 1st, 2nd and 3rd postoperative months. The GoE females had significant bodyweight augmentation and their plasma estrogen concentration decreased by 40-45% by the 1st postoperative month, while in males the testosterone level was not detectable after gonadectomy. Leukocyte and platelet counts moderately increased in GoE males. Elongation index values of erythrocytes slightly decreased in both genders after gonadectomy, showing converging values. Erythrocyte aggregation index values of GoE females significantly raised by the 2nd month. It can be concluded that gonadectomy in rats resulted in alteration (dominantly impairment) of blood microrheological parameters, by different manner in males and females. Supposedly decrease in estrogen can cause more expressed hemorheological changes than the cessation of testosterone.
Clinical hemorheology and microcirculation 01/2012; 50(4):231-43. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: It is known that hemorheological parameters show gender differences that might be altered by gonadectomy (GoE). Since micro-rheological parameters (erythrocyte deformability and aggregation) sensitively change during and after ischemia-reperfusion (I/R), the question arises whether the hemorheological effects of I/R may show gender differences and further changes might be expected when GoE and I/R are additive. Sprague-Dawley rats were divided into six groups: Control males and females, I/R males and females with 1-hour hind limb ischemia, GoE + I//R males and females when 3 months after bilateral gonadectomy the I/R was induced. Before and just after ischemia, and on the 1st-3rd-5th-7th postoperative days blood samples were taken (lateral tail vein, 0.3-0.5 mL) for analyzing hematological parameters, erythrocyte's deformability (slit-flow ektacytometer) and aggregation (light-transmission aggregometer). Leukocyte and platelet counts raised markedly in gonadectomized animals during the investigated days. Hemorheological changes of I/R showed gender differences: significant impairment of erythrocyte deformability was found on the 1st-3rd postoperative days, expressed mostly in females. In gonadectomized females the postischemic deformability values were impaired. Erythrocyte aggregation index significantly raised by the 1st postoperative day, dominantly in males. It is suggested that gonadectomy may act as an additional rheological 'risk factor' related to blood micro-rheological parameters in ischemia-reperfusion.
Clinical hemorheology and microcirculation 01/2012; 50(3):197-211. · 3.40 Impact Factor
-
Timea Hever,
Norbert Nemeth,
Endre Brath,
Laszlo Toth, Ferenc Kiss,
Erika Sajtos,
Lili Matyas,
Janos Szaszko,
Laszlo Drimba,
Barna Peitl,
Zoltan Csiki,
Iren Miko,
Istvan Furka
[show abstract]
[hide abstract]
ABSTRACT: Artificial femoral arterio-venous (AV) shunts are widely used in rodent models for studying shunt maturation and to optimize various surgical techniques. However, little is known about complex circulatory, microcirculatory, and hemorheological effects of end-to-side saphenous AV shunts. We aimed to study these parameters in mature AV shunts. Studying these questions in CD rats, end-to-side anastomoses were made between the left saphenous artery and vein. On the right-side the nonoperated saphenous vessels served as own control. Furthermore healthy control animals were also investigated. On the 8th to 12th postoperative week microcirculatory and blood flow measurements were performed and blood samples were taken both from the shunt's arterial and venous limbs and from the nonoperated side vessels. Hematological parameters, erythrocyte aggregation, and deformability were determined. The entire shunt and the control vessels were removed for histological examinations. The skin microcirculation on shunt side slightly increased on thigh and decreased on paws versus the nonoperated side. Blood flow measurements made directly on the vessels showed that arterial to venous blood flow rate ratio was 1.59 ± 0.29 on nonoperated side and 1.2 ± 0.13 on the shunt side, and 1.49 ± 0.05 in control animals. Erythrocyte aggregation and deformability worsened on the shunt side. Histologically increased number of smooth muscle elements and connective tissue were found in venous limb of the shunts. The artificial AV shunt between the saphenous artery and vein seems to be a suitable model for further functional-morphological and hemorheological examinations of hemodialysis in various states and diseases.
Microsurgery 11/2010; 30(8):649-56. · 1.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Although growing number of evidences supports the gender differences of hemorheological variables in human, little is known about this question in experimental animals. Investigating this question and giving laboratory-specific reference values, blood samples from healthy male and female CD rats and beagle dogs were tested for hematological parameters (microcell counter), blood and plasma viscosity (capillary viscometer), erythrocyte deformability (bulk filtrometry and ektacytometry), erythrocyte aggregation (light transmission aggregometer) and fibrinogen concentration (coagulometer). Besides the inter-species alterations we found hematological gender differences too regarding the red blood cell count and hematocrit. In rats the erythrocyte aggregation index was higher in females, while in beagle dogs the males showed significantly higher aggregation index values. In rats the red blood cell deformability showed better values in females. In beagle dogs this was the opposite, the males had better elongation index (EI) values in the function of shear stress (SS). Besides this it was also experienced that the shape of the canine EI - SS curves differed from the rats' values. Gender differences with inter-species alterations can be observed in laboratory animals (rats and dogs) that have to be taken under consideration during planning experiments and evaluating results.
Clinical hemorheology and microcirculation 01/2010; 45(2-4):263-72. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Using "Furka's spleen-chip" autotransplantation technique, in a follow-up study we investigated erythrocyte aggregation and its influencing factors regarding to asplenic-hyposplenic conditions. Healthy beagle dogs were equally divided into 4 groups: "Sham"- sham operated control, "SE"-splenectomy, "AU-5" and "AU-10"-autotransplantation with 5 or 10 spleen chips by Furka-method after splenectomy. Blood sampling for current investigation occurred on the 12th, 18th, 20th and 24th postoperative months, besides comprehensive structural and functional examinations. In this study we focused on the aggregation properties of erythrocytes in native samples and of density separated "young" versus "old" erythrocytes (Myrenne MA-1 aggregometer). Fibrinogen concentration (Sysmex CA-500 coagulometer) and erythrocyte sedimentation rate (ESR) were also determined. SE group showed significantly elevated ratio of "old" and "young" erythrocyte aggregation index values on the 20th and 24th postoperative months (1.5 and 2.16, respectively) comparing to the AU (1.14 and 1.05) and Sham groups (1.2 and 1.27). In SE group fibrinogen concentration was mildly higher and ESR almost doubled versus control. The greater differences experienced between "young" and "old" erythrocytes may reflect decreased splenic filtration function. Consequently, the comparison of aggregation and deformability properties of "young" and "old" erythrocytes may give important information about the function of the spleen.
Clinical hemorheology and microcirculation 01/2010; 45(2-4):273-80. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Erythrocyte deformability could be a suitable parameter reflecting hyposplenic-asplenic conditions after splenectomy or spleen autotransplantation. The aim of this study was to analyze the efficacy of spleen autotransplantation using filtrometry and ektacytometry for testing erythrocyte deformability, besides complex structural, functional, hematological, hemostaseological and immunological examinations. Healthy beagle dogs were subjected to the study in the following experimental groups: "Sham"-sham operated control, "SE"-splenectomy, "AU-5" and "AU-10"-autotransplantation with 5 or 10 spleen chips using "Furka's spleen chip" technique after splenectomy. Blood samples were taken before the operations and monthly afterwards for 1 year and bi-monthly till the end of the 2nd postoperative year. Erythrocyte deformability was measured by bulk filtrometry (relative cell transit time, RCTT) and on the 20th-24th postoperative months by ektacytometry (elongation index, EI), too. RCTT was elevated in operated groups till the 12th month. On the 20th/24th months "SE"-group expressed the highest level, while the "AU"-groups were close to "Sham"-group. Using ektacytometer we found that on the 20th/24th month both EImax and SS1/2 showed the lowest values (because of unusual curve characteristic) in "SE"-group and "AU"-groups almost reached the "SH"-group. Spleen autotransplantation partially restored the normal rheological conditions. Both filtrometry and ektacytometry was suitable to investigate hyposplenic-asplenic conditions.
Clinical hemorheology and microcirculation 01/2010; 45(2-4):281-8. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Clinical studied showed leukocyte antisedimentation rate (LAR) changes in various conditions that modulate the immune system. There is a lack of LAR data in animal experiments concerning splenic function after splenectomy or spleen preserving operations, thus we aimed to include LAR in our ongoing inbred canine study on following-up spleen salvaging surgical techniques. Blood samples of healthy beagle dogs served as normal control. The experimental groups were: "SH"-sham operated, "SE"-splenectomy, "R1/3" and "R2/3"-one-third/two-third of the spleen resected, "AU-5" and "AU-10"-autotransplantation with 5/10 spleen chips using Furka's techniques. On the 12th postoperative month Rabigen-Mono+Vanguard-Plus-5 vaccines were given to the animals, which provoked immune response. Blood samples were taken before and one week after the vaccination. LAR was calculated by Bogar's method. In normal control group LAR was 3.11, leukocyte count was 12.04 G/l. In the experimental groups LAR varied between 2.4-7.3 before vaccination. After vaccination LAR increased in all groups. Although "SE" group expressed the largest changes (LAR = 16.56; 135%), the leukocyte count increased only by 12%. In "AU" groups the increase was smaller, while "R" groups showed slight changes only. LAR can be applicable in animal experiments and may serve as a supplementary parameter in hemorheological investigations of hyposplenic-asplenic states.
Clinical hemorheology and microcirculation 01/2010; 45(2-4):289-94. · 3.40 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of this study was to investigate intestinal ischemia-reperfusion and its local and systemic hemorheological relations in the rat. Ten anaesthetized female CD outbred rats were equally divided into 2 experimental groups. (1) Ischemia-reperfusion (I/R): the superior mesenterial artery was clipped for 30 minutes. After removing the clip, 60 minutes of the reperfusion was observed before extermination. Blood samples were taken from the caudal caval vein and from the portal vein before ischemia, 1 minute before and after clip removal, and at the 15th, 30th, and 60th minutes of the reperfusion. (2) Sham operation: median laparotomy and blood sampling were done according to the timing as in I/R group. Hematological parameters, red blood cell aggregation, and deformability were determined. Leukocyte count and mean volume of erythrocytes increased slightly but continuously in portal venous samples during the reperfusion period. Red blood cell aggregation values were higher in portal blood by the end of ischemia, and then became elevated further comparing to the caval venous blood. Both in caval and portal venous samples of I/R group red blood cell deformability significantly worsened during the experimental period compared to its base and Sham group. In portal blood red blood cell deformability was impaired more than in caval vein samples. Histology showed denuded villi, dilated capillaries, and the inflammatory cells were increased after a 30 minutes ischemia. In conclusion, intestinal ischemia-reperfusion causes changes in erythrocyte deformability and aggregation, showing local versus systemic differences in venous blood during the first hour of reperfusion.
Microsurgery 09/2009; 30(4):321-6. · 1.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Measuring erythrocyte deformability with bulk filtrometers is common, but there are problems with standardization and sample quantity in small laboratory animals. In this study, blood was drawn from mice, rats, and dogs, and then erythrocyte suspensions at 1-5% hematocrit were prepared. Bulk filtrometers with a 5- or 3-microm pore-diameter filter were used to determine the initial relative filtration rate (IRFR) and relative cell transit time (RCTT). Hematological composition was also tested. In all species, the highest IRFR values occurred at 1% hematocrit, and the lowest values at 5%. In mice and rats, RCTT values were lowest at 1% and highest at 5% using a 5-microm filter, whereas in dogs, RCTT was elevated at 1-2%. Using a 3-microm filter, each species showed the same phenomena under 3%. RCTT values may become distorted above a certain cell-size/pore-size ratio. In mice and rats, 1% suspension is applicable for bulk filtrometry, but only using 5-microm filters.
Microsurgery 02/2006; 26(1):33-7. · 1.61 Impact Factor
-
Ph.D. Norbert Nemeth M.D,
Adrienn Gulyas,
Anita Balint M.D,
Katalin Peto M.D,
Endre Brath M.D, Ferenc Kiss,
Istvan Furka M.D., Ph.D., D.Sc,
Ph.D. Oguz K. Baskurt M.D,
Ph.D. Iren Miko M.D
[show abstract]
[hide abstract]
ABSTRACT: Measuring erythrocyte deformability with bulk filtrometers is common, but there are problems with standardization and sample quantity in small laboratory animals. In this study, blood was drawn from mice, rats, and dogs, and then erythrocyte suspensions at 1–5% hematocrit were prepared. Bulk filtrometers with a 5- or 3-μm pore-diameter filter were used to determine the initial relative filtration rate (IRFR) and relative cell transit time (RCTT). Hematological composition was also tested. In all species, the highest IRFR values occurred at 1% hematocrit, and the lowest values at 5%. In mice and rats, RCTT values were lowest at 1% and highest at 5% using a 5-μm filter, whereas in dogs, RCTT was elevated at 1–2%. Using a 3-μm filter, each species showed the same phenomena under 3%. RCTT values may become distorted above a certain cell-size/pore-size ratio. In mice and rats, 1% suspension is applicable for bulk filtrometry, but only using 5-μm filters. © 2006 Wiley-Liss, Inc. Microsurgery 26: 33–37, 2006.
Microsurgery 12/2005; 26(1):33 - 37. · 1.61 Impact Factor
-
Norbert Németh,
Tamás Lesznyák,
Miklós Szokoly,
Endre Bráth,
Katalin Peto,
Györgyi Szabó,
Adrienn Gulyás, Ferenc Kiss,
Sándor Imre,
István Furka,
Irén Mikó
[show abstract]
[hide abstract]
ABSTRACT: Rheological properties of the blood are determined by several factors and if they change it may be diagnostic for many diseases. It is well-known that during ischemia and reperfusion different free-radical liberating pathways are inducted besides the local physical and metabolical changes. These processes may harm red blood cells by increasing their rigidity and impairing their deformability. In ischemia-reperfusion models measurements of erythrocyte deformability is important. Characteristic alterations were observed in both rat and dog hind limb ischemia-reperfusion with vascular clamping on femoral vessels for 1 or 3 hours. Erythrocyte deformability was significantly impaired on the postoperative 1st-3rd days. The acute limb ischemia-reperfusion experimental models seem suitable for further in vivo rheological studies.
Magyar Sebészet (Hungarian Journal of Surgery) 05/2005; 58(2):144-7.
