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PubMed2001

[Central hemodynamics and microcirculation in hypertensive patients with influenza or other acute respiratory viral infections].

Integral rheography and conjunctival biomicroscopy studied central hemodynamics (CH) and microcirculation (MC), respectively, in 37 hypertensive patients with influenza and acute respiratory viral infection (ARVI) and 38 normotensive patients with influenza and ARVI aged 41 to 94 years (group 1 and 2, respectively). In group 1 vs group 2 specific peripheral resistance was significantly higher, intravascular changes were more manifest (disseminated aggregation of red cells, slow blood flow with its incomplete block. It is shown that patients with influenza and ARVI had main functional circulatory disorders in microcirculation zone. The study of microcirculation by conjunctival biomicroscopy is important for these patients for assignment of pathogenetically sound vascular therapy, first of all disaggregants.

Acute Disease↗

PubMed2001

[Microcirculation, hemostasis, and hemorheology in influenza and acute respiratory viral infections in patients with hypertension].

AIM: To study microcirculation (MC), hemostasis (HS) and blood viscosity (BV) in influenza and acute respiratory viral infection (ARVI) in hypertensive patients. MATERIAL AND METHODS: The study group consisted of 67 hypertensive patients with influenza or ARVI. 45 influenza and ARVI normotensive subjects served control. HS and BV tests were made, conjunctival biomicroscopy was performed. RESULTS: Patients with influenza and ARVI in the acute period had distinct perivascular and vascular abnormalities, sludge phenomenon in the majority of postcapillary venules and capillaries. In convalescence microcirculation improved. HS in the acute stage of infections was characterized by fast coagulation, depression of fibrinolysis; in convalescence, a significantly enhanced platelet aggregation was seen. The highest BV occurred at low shift speeds. Hypertensive patients had higher vascular permeability and more severe intravascular changes which presented with disseminated intravascular red cell aggregation, slowing down of blood flow, its partial block. In hypertension there was also significantly higher platelet aggregation, lower disaggregation, higher BV increase in convalescence. CONCLUSION: Hypertensive patients with influenza or ARVI had serious disorders of microcirculation, HS and BV threatening cardiovascular complications in such patients.

Acute Disease↗

PubMed2001

[The effect of L-arginine on the microcirculation reperfusion of cremaster muscle in rats].

OBJECTIVE: To investigate the effect of L-arginine and the role of nitric oxide (NO) on the microcirculation of cremaster muscle after the ischemia-reperfusion. METHODS: A group of male Sprague-Dawley rats, each weighing 180-220 g, were surgically prepared with the neurovascular bundle freed only to connect to the cremaster muscle, subjected to 5 hours warm ischemia and 2 hours of reperfusion, and treated with L-arginine. The microcirculation was observed with the measurement of the arteriole in diameter under intravital microscopy. RESULTS: 1. The arteriole re-flowing with the L-arginine treatment was significantly higher than the saline control with only 53% in 30 minutes after the reperfusion (P < 0.01). 2. The diameter of the reflowed arteriole and the perfused capillary density were increasing greatly with the L-arginine treatment, compared to the control group. 3. The pathological phenomena of "only irrigation and no reflow" was observed in local muscle microcirculation, which subsequently resulted in the large-scale leakage hemorrhage. CONCLUSIONS: The nitric oxide product could relieve the vasospasm and decrease the no-reflow of skeletal muscular during reperfusion; The venular no-reflow resulted from venular thrombi may play an important part during the tissue reperfusion injury.

Animals↗

PubMed1975

[Microcirculation index--screening parameter for the assessment of dynamics of the terminal vascular system].

In this paper a new diagnostic method for the judgment of the dynamics of the terminal vascular system is presented. The microcirculation index which is to be obtained by means of the special technique of the phlebembraxis plethysmography was developed in investigations lasting several years and it was tested on persons with normal blood pressure and on hypertonics in comparison to recognized reference methods. Age-specific normal values were established and the differences found between normo- and hypertonics as well as between different decenniums were statistically ascertained. One group of hypertonics which underwent an antihypertensive long-term therapy showed a significant improvement of the microcirculation index after 8 weeks. According to the hitherto got results this index is fully suited for the utilization as screening method for serial examinations within the X-ray mass examinations and the research of cardio-criculatory diseases. It especially allows the selection of hypertonics who need treatment and through the increasing use of the multi-channel-occlusion-plethysmograph developed by the author the application in routine work for the judgment of the microcirculation and its influence by an antihypertensive therapy. For further foundation of the findings comparative methods with additional reference methods, especially electron microscopy are provided.

Adult↗

PubMed1975

[Study of the microcirculation of the wall of the stomach of white rats by the vital microscopy method].

Microcirculation of the gastric wall in the albino rat was studied by the method of vital microscopy in passing light. The conditions of the experiment permitted watching the microcirculation state during 5-6 hours. Intravital morphometry of the microcirculation bed vessels was made. The obtained data concerning the intravital angioarchitectonics of the gastric wall vascular bed were in good agreement with a conventional scheme of its blood supply. The role of arteriolevenular anastomoses in redistribution of blood within the bloodflow pathways was noted.

Animals↗

PubMed1999

[Effects of tea polyphenols on microcirculation and antioxidation in aircrew].

OBJECTIVE: To study the effects of tea polyphenols (TP) on bulbi conjunctiva microcirculation (BCM) and antioxidation in aircrew and find out the proper antioxidant for the health protection of aircrew. METHOD: Fourty healthy aircrew were divided into TP group (TP 600 mg/d.po) and control group (placebo) randomly. The effects of TP on microcirculation and antioxidation in aircrew were tested after 20 days. RESULT: Red blood cell (RBC) superoxide dismutase (SOD) activity and GSH-PX (Whole blood glutathione peroxidase)/MDA (serum malondialdehyde) ratio in TP group were significantly higher than those in control (P<0.01), and serum MDA level was significantly decreased after TP administration (P<0.05). The numbers of capillaries and blood flow in micrangium were significantly increased, RBC aggregation, ischemia area and A (arteriole)/V (venule) ratio were remarkably decreased in TP group (P<0.01). The total integral value of microcirculation in TP group was significantly reduced in comparison with that in the control group. CONCLUSION: TP can significantly increase the antioxidative ability of aircrew, decrease the BCM disturbance and improve the microcirculatory function.

Adult↗

PubMed1975

Changes in microcirculation and oxygen pressure in the liver and kidneys in experimental traumatic shock.

Changes in microcirculation and oxygen pressure in the liver and kidneys were studied in experiments on 42 rats in the course of experimental traumatic shock elicited by Cannon's methoicroscope with a microphoto adapter MFN-12. Oxygen pressure was recorded with the aid of active open hemispheric platinum electrodes with diameters of 150-200 mum. With advencing shock, considerable disturbances of microcirculation and PO2 occurred in hepatic and renal tissues. By the end of the torpid phase of the shock, the PO2 in the liver sank to 1/2.4, and in the kidneys, to less than 1/4 of the respective initial values. The changes in microcirculation were of an ischaemic, vasospastic type in the kidneys, and of a mosaic pattern in the liver: ischaemic segments alternated with areas fully supplied with blood. A severe and rapid course of shock was accompanied by more marked disturbances of PO2 and circulation in hepatic and renal terminal vessels.

Animals↗

PubMed2002

[Effect of fluvastain and its combination with aspirin and trental on hemostasis and microcirculation in atherosclerosis].

AIM: To assess effects of fluvastatin monotherapy and combined therapy with aspirin and trental on hemostasis and microcirculation in atherosclerosis. MATERIAL AND METHODS: Hemostasis and microcirculation were studied in 68 patients with coronary atherosclerosis and aortic atherosclerosis on fluvastatin monotherapy and on combined therapy fluvastatin + aspirin + trental. RESULTS: Hypolipidemic treatment with fluvastatin reduced thrombogenic blood potential due to enhancement of plasmic fibrinolytic activity [the time of XII-a dependent fibrinolysis decreased by 33% (p < 0.05)], decreased thrombinemia [blood level of soluble fibrin-monomeric complexes fell by 44% (p < 0.05)] and reduced stimulated platelet aggregation: by 18.2% in response to ADP (p < 0.05) and by 11% in response to adrenalin (p < 0.05). CONCLUSION: Correction of lipid metabolism and blood hypercoagulation improved microrheology. Combination of fluvastatin with aspirin made platelet aggregation reduction in response to both inductors faster and more stable, while combination of fluvastatin with trental contributed to better results in microcirculation improvement.

Adult↗

PubMed2002

[The state of microcirculation in hypertensive disease (essential hypertension)].

Skin microcirculation was studied by laser doppler flowmetry in 149 patients with essential hypertension (92 men, 67 women; mean age 50.1+/-4.9 years) and in 25 normotensive controls. In patients with hypertension prevailed pathological hemodynamic types of microcirculation. Hyperemic, spastic and congestive types were found in 20.1, 23.5 and 40.3% of patients, respectively, while only 16.1% of patients had normal hemodynamic type. Moreover presence and severity of microcirculatory disorders depended on stage of hypertension and level of blood pressure. Thus, patients with essential hypertension had pronounced impairment of microcirculation caused by structural and functional changes of microcirculatory vascular bed.

Adult↗

PubMed2002

[Effects of nebivolol on microcirculation, platelet aggregation and blood viscosity in patients with essential hypertension].

AIM: To assess effects of a selective beta1-adrenoreceptor blocker acting in part via nitric oxide nebivolol on microcirculation, platelet aggregation and blood viscosity. MATERIAL: Thirty patients with mild-to-moderate essential hypertension (mean age 54,1-/+9,3 years). METHODS: Ambulatory blood pressure monitoring, laser doppler flowmetry, registration of spontaneous and ADP-induced platelet aggregation. Nebivolol (5 mg/day) or its combination with hydrochlorothiazide (12,5 mg/day) were given for 3 months. RESULTS: Treatment with nebivolol caused significant reduction of systolic and diastolic blood pressures. Spontaneous and low dose ADP-induced platelet aggregation significantly decreased during treatment while blood viscosity did not change. In patients with hyperemic and spastic-hyperemic hemodynamic type of microcirculation improvement of microcirculation occurred due to changes of myogenic tone of arterioles and precapillary sphincters and 'damping' properties of resistance arterioles. CONCLUSION: In patients with essential hypertension hypotensive action of nebivolol was associated with antiaggregation effect and improvement of blood flow in microvascular networks.

Adult↗

PubMed2001

[Immediate microcirculation reaction of periodontal ligaments to experimental intrusion of dog teeth].

OBJECTIVE: The purpose of this study is to investigate the immediate microcirculation reaction of periodontal ligaments to experimental intrusion of dog teeth. METHODS: The forth premolar was chosen as the anchor tooth to intrude the second premolar using an intrusion circle loop. All tissue sections were observed and analyzed using the ink perfusion technique and an image analysis apparatus. RESULTS: The microvascular pattern of periodontal ligaments was changed after the maxillary second premolar had been intruded for 2 hours with 100 g of force. The vascular diameter and volume density diminished, but the vascular number and some parts of the microvasculature, especially capillaries were compressed due to the blood escaping from the periodontal ligament. It showed that the initial effect of 100 g of intrusive force caused adaptable changes in the microcirculation of periodontal ligaments, but no significant impediment of blood flow occurred. CONCLUSION: During the tooth intrusion with 100 g of force, a suitable microenvironment was established for the benefit of the survival of periodontal ligaments, which could avoid overloads imposed on the periodontal ligament and decreased the injury of periodontal tissue. It elucidates that the microcirculation of periodontal ligaments plays an important role in the protection of the periodontal tissue, in terms of biological function.

Animals↗

PubMed2002

[The effects of dieda zhentong liquid on ear microcirculation of rabbit].

OBJECTIVE: To observe the effects of Dieda Zhentong Liquid (DDZTL) on ear microcirculation of rabbits. METHODS: With microcirculation apparatus, caliber of micrangium, velocity and volume of blood flow were detected in experimental groups. RESULTS: The volume of blood flow of DDZTL group without Chlorophytum laxum haven't an increase compared with that of the group without administering the medicinal liquid. Shexiang Shuhuo Essence group, Chlorophytum laxum group, high and low dose DDZTL group have an increase. CONCLUSION: DDZTL could improve ear microcirculation of rabbit. Chlorophytum laxum maybe play an important role in above-mentioned effect.

Animals↗

PubMed2002

[Disturbances in microcirculation--an early predictor of arterial hypertension?].

The aim of this study was to assess microcirculation and properties of large arteries in healthy adult subjects. In 28 individuals between the ages of 21 and 49, the microcirculation in the skin at resting conditions and under stimulation (hyperaemic reaction after a 3-minute long ischaemia at basal body temperature and at 44 degrees C) was measured with laser doppler flowmetry detection. Pulse Wave Velocity was measured by using Complior device and average values of blood pressure were calculated. Subjects were divided into two groups based on the median (pLDF = 374.5) of the hyperaemic reaction after ischaemia at basal body temperature (14 persons in each group). There were no significant differences in the age and pulse wave velocity in both groups. The group after ischaemia at basal body temperature was characterized by significantly lower values of the resting flow, higher values of blood pressure, and higher values of increase in flow after ischaemia when compared to the group after ischemia at 44 degrees C. Furthermore, there was a positive correlation between values in flow after ischaemia at basal body temperature and at 44 degrees C with systolic blood pressure (r = 0.79 and 0.62, respectively). Presented results suggest that disturbances in microcirculation can precede development of hypertension.

Adult↗

PubMed2003

Microcirculation associated with degenerative rotator cuff lesions. In vivo assessment with orthogonal polarization spectral imaging during arthroscopy of the shoulder.

BACKGROUND: Diminished vascular supply is associated with degenerative rotator cuff lesions. Orthogonal polarization spectral imaging allows noninvasive assessment of microcirculation without application of fluorescent contrast medium. The aim of our study was to visualize and quantify in vivo the microcirculation of the rotator cuff during arthroscopic surgery and to compare the results with the number of microvessels identified in vitro by immunostaining of biopsy specimens taken from the scanned areas. METHODS: Eleven patients with clinical signs of a degenerative rotator cuff lesion were studied. Prior to arthroscopic subacromial decompression, the superficial part of the supraspinatus tendon at the edge of the lesion as well as the unaffected tendon insertion was examined. Microvascular parameters established for the description of tissue perfusion with use of conventional intravital fluorescence microscopy (functional capillary density and capillary diameter) were assessed in vivo. Biopsy specimens were taken from the scanned areas, and the microvessels were localized by immunostaining for the endothelial surface marker CD31. RESULTS: In the region of the unaffected tendon insertion, the mean baseline functional capillary density (and standard deviation) was 106 +/- 13 cm/cm(2) and the mean capillary diameter was 10 +/- 0.7 microm. In contrast, at the edge of the lesion, the functional capillary density was significantly reduced to 20 +/- 14 cm/cm(2), whereas the diameter of the vessels that were present did not differ. The total number of vessels stained in vitro was also significantly reduced at the edge of the lesion compared with the number of vessels in the tendon insertion zone. CONCLUSIONS: Quantitative in vivo analysis of human microcirculation during arthroscopy demonstrated that the functional capillary density at the edge of a degenerative rotator cuff lesion was significantly reduced compared with that in the control tissue. The capacity to assess microcirculatory flow in vivo may help to identify specific repair strategies based on knowledge of individual perfusion patterns.

Arthroscopy↗

PubMed2003

[Clinico-morphological features of acute gastroduodenal erosion and ulcers in an unstable course of myocardial ischemia and role in disturbances of microcirculation, stomach function and their development].

AIM: Determination of clinicomorphological characteristics of acute gastroduodenal erosions and ulcers in unstable course of IHD and the role of disorders in microcirculation, hemostasis, gastric function in development of these erosions. MATERIAL AND METHODS: Clinically and endoscopically were examined 124 patients with unstable IHD. By detected gastroduodenal changes the patients were divided into three groups. The study was also made of local and systemic microcirculation, hemostasis, gastric functions. RESULTS: Acute gastroduodenal erosions and ulcers in unstable course of ischemic heart disease manifest with mild abdominal pains and gastric dyspepsia for several days. Disorders in the gastroduodenal zone arise because of focal disturbances of terminal circulation in the mucose according to thromboischemic or thrombohemorrhagic types related to generalized changes of microcirculation and hematasis. High activity of acid-peptic factor, low production of gastromucoproteins and hypomotor dyskinesia of the stomach contribute to development of erosive-ulcerous lesions. CONCLUSION: The above information is useful for early diagnosis of acute gastroduodenal erosions and ulcers in unstable course of IHD and upgrading of therapeutic measures.

Aged↗

PubMedDate not supplied

RES function and liver microcirculation in the early stage of acute experimental pancreatitis.

BACKGROUND/AIMS: The reticuloendothelial system and in particular the Kupffer cells in the liver are important for eliminating antigens and toxic substances in many diseases including acute pancreatitis. Optimal Kupffer cell function is believed to depend on numerous factors including intact hepatic blood supply and microcirculation. The aim of the study was to evaluate whether hepatic microcirculation and Kupffer cell function are impaired in acute pancreatitis and whether enhancement of hepatic capillary blood flow leads to improved reticuloendothelial system function. METHODOLOGY: Acute pancreatitis was induced in rats by intraductal infusion of bile salt followed by i.v. cerulein hyperstimulation. Animals were randomized to receive either a selective endothelin-A receptor antagonist (ET-RA; LU-135252; 50 mg/kg) or saline. Sham-operated animals (intraductal and i.v. saline infusion) treated according to the same protocol served as controls. Liver phagocytic function was evaluated in 6 animals per group 6 and 24 hrs after acute pancreatitis induction and treatment using 99mTc-labeled Nanocoll and a scintillation camera technique. Another 6 animals of each group were used for intravital microscopic determination of hepatic capillary blood flow using fluorescein-labeled erythrocytes. RESULTS: Six hours after acute pancreatitis induction, hepatic capillary blood flow and nanocoll clearance were significantly decreased in saline-treated animals (compared to saline-treated healthy controls). Endothelin-A receptor antagonist significantly improved hepatic capillary blood flow and nanocoll clearance. This beneficial effect was no longer seen after 24 hrs when these parameters had spontaneously returned to values not significantly different from normal. CONCLUSIONS: Reticuloendothelial system function and hepatic capillary blood flow are impaired (only) in the early stage of this acute pancreatitis model. Endothelin-A receptor antagonist improves hepatic capillary blood flow at this stage. Enhancement of hepatic capillary blood flow is accompanied by normalization of nanocoll clearance, suggesting that hepatic microcirculation influences phagocytic Kupffer cell function early in acute pancreatitis.

Acute Disease↗

PubMed2003

[Changes in microcirculation of esophageal mucosa during acute experimental reflux. Pathogenic role of the biliary component].

UNLABELLED: Our aims were to examine microcirculation during experimental reflux esophagitis in dogs. We compared the effects of microcirculation of the mucosa to 3-hr exposure with acid, mixed acid and bile, we measured the changes in constitutive and inducible nitric oxide synthase activity (cNOS and iNOS). METHODS: The microcirculation of the upper esophagus was investigated by intravital videomicroscopy. The functional capillary density (FCD), relative vessel area (RVA) and red blood cell velocity (RBCV) were measured. Mucosal barrier integrity was examined by vascular and epithelial permeability indices. Myeloperoxidase (MPO) enzyme activity, cNOS, iNOS activities and microscopic damage were examined in biopsies. RESULTS: The vascular permeability index, the RBCV and the RVA increased significantly in the treated groups, the FCD significantly decreased after acid exposure. The MPO and iNOS activities were significantly elevated in all treated groups. The cNOS activity did not change after exposure to acid + bile or acid, but significantly decreased after sole bile treatment. Severe mucosal damage was observed after bile exposure. CONCLUSION: Bile induced characteristic microcirculatory changes during experimental reflux esophagitis. Tissue damage and leukocyte infiltration could be exacerbated by bile-induced cNOS inhibition.

Animals↗

PubMed2003

[Hemodynamics and microcirculation in a rat poisoned by scorpion venom]].

The clinic table of serious scorpionic envenimation is dominated by cardiovascular and pulmonary perturbations. The physiopathology of cardiac failure in man as well as at animal is again badly elucidated. The aim of our study has consisted in evaluating the hemodynamic variations of the Rat poisoned by the venom of the Buthus occitanus scorpion and to contribute through the analyse of plasmatic concentrations of catecholamines and by an histomorphometric study of muscular microcirculation to explain the mechanism of the hemodynamic perturbations and cardiac failure. 51 rats corresponding to 9 groups (witness and poisoned) have been used. The venom of the scorpion Buthus occitanus has been administrated at 850 micrograms/kg. Two groups have been served for hemodynamic study, three groups for the dosage of catecholamines and four groups for histomorphometric study. It has been observed a biphasic variation of arterial pressure and cardiac frequency after venom injection. Four minutes after envenimation, the plasmatic level of catecholamines was strongly higher in the poisoned according to the witness one. Histomorphometric study of muscular skeletal microcirculation has shown a decrease of relative vascular volume contemporary with the increase of plasmatic catecholamines concentration and the peak of arteriel pressure appeared just after envenimation. 10 and 20 minutes after envenimation, the relative vascular volume has significantly increased as well as that interstitium according to witness lot. These hemodynamic perturbations can be attributed to the important dump in catecholamines. This hyperadrenergy was contemporary with decrease of relative muscular vascular volume. This decrease would be explained by a constriction of vessels. On the other hand, the second increase of the vascular relative volume suggests the possibility of development of venous stasis at the muscular microcirculation. It would be induced by a cardiac failure and/or the effect of vasoplegic mediators being able to entail an interstitial oedema in the muscular skeletal that would led to increase the relative interstitial volume observed in this study.

Animals↗