Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Microcirculation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed2003

Dynamic deformation of migratory efferent lymph-derived cells "trapped" in the inflammatory microcirculation.

The cellular immune response depends on the delivery of lymphocytes from the lymph node to the peripheral site of antigenic challenge. During their passage through the inflammatory microcirculaton, the migratory cells can become transiently immobilized or "trapped" in small caliber vessels. In this report, we used intravital microscopy and temporal area mapping to define the dynamic deformation of efferent lymph-derived mononuclear cells trapped in the systemic inflammatory microcirculation. Mononuclear cells obtained from the efferent lymph draining the oxazolone-stimulated microcirculation were labeled with fluorescent dye and reinjected into the feeding arterial circulation. Intravital video microscopy observed thousands of cells passing through the microcirculation; 35 cells were "trapped" in the oxazolone-stimulated microcirculation. Temporal area maps of the trapped cells demonstrated dramatic slowing and deformation. The cells were trapped in the microcirculation for a median of 8.90 sec (range 5-17 sec) prior to returning to the flow stream. During this period, the cells showed sustained movement associated with both antegrade locomotion (mean cell velocity = 7.92 microm/sec; range 1.16-14.23 microm/sec) and dynamic elongation (median cell length = 73.8 microm; range 58-144 microm). In contrast, efferent lymph-derived cells passing unimpeded through the microcirculation demonstrated rapid velocity (median velocity = 216 microm/sec) and spherical geometry (median diameter = 14.6 microm). Further, the membrane surface area of the "trapped" cells, calculated based on digital image morphometry and corrosion cast scanning electron microscopy, suggested that the fractional excess membrane of the cells in the efferent lymph was significantly greater than previous estimates of membrane excess. These data indicate that transient immobilization of efferent lymph-derived mononuclear cells in the systemic inflammatory microcirculation is rare. When "trapping" does occur, the shape changes and sustained cell movement facilitated by excess cell membrane may contribute to the return of the "trapped cells" into the flow stream.

Adjuvants, Immunologic↗
PubMed2000

1998 Distinguished Lecture: biomechanics of the microcirculation, an integrative and therapeutic perspective.

The microcirculation, integratively speaking, is distensible and contains 40%-50% of the total blood volume. Other than the mission of mass transport, the microcirculation and its endothelial cells have the role of regulation, signal transduction, proliferation, and repair. In this article, the emphasis is on the integrative role of the microcirculation on circulatory control and its therapeutic role on blood volume compensation. To introduce this topic, I first summarize the morphometry data on the blood volume distribution in the coronary, pulmonary, and mesentery circulation and then review the methodology developed in my laboratory to assess the microvascular volume change or shift of blood volume from microcirculation to macrocirculation. Evidence obtained through these studies indicates that the microcirculation can play a more important role as a reservoir to compensate for blood volume loss than the venous system. Reanalysis of published data also indicates that microvascular pooling, not hypovolemia, is the likely factor causing endotoxin shock or hypotension for hemodialysis patients. Understanding of the role of the microcirculation could lead to more effective diagnosis of cardiovascular deficiency and therapy for hypotension or low cardiac output with intervention through the microcirculation.

Animals↗
PubMed2001

Focal topographic changes in inflammatory microcirculation associated with lymphocyte slowing and transmigration.

Microcirculation is the primary mechanism for delivering lymphocytes to inflammatory tissues. Blood flow within microvessels ensures a supply of lymphocytes at the blood-endothelial interface. Whether the structure of the inflammatory microcirculation facilitates lymphocyte transmigration is less clear. To illuminate the microcirculatory changes associated with lymphocyte transmigration, we used intravital videomicroscopy to examine the dermal microcirculation after application of the epicutaneous antigen oxazolone. Intravascular injection of fluorescein-labeled dextran demonstrated focal topographic changes in the microcirculation. These focal changes had the appearance of loops or hairpin turns in the oxazolone-stimulated skin. Changes were maximal at 96 h and coincided with peak lymphocyte recruitment. To determine whether these changes were associated with lymphocyte transmigration, lymphocytes obtained from efferent lymph of draining lymph nodes at 96 h were fluorescently labeled and reinjected into inflammatory microcirculation. Epifuorescence intravital video microscopy demonstrated focal areas were associated with lymphocyte slowing and occasional transmigration. In contrast, focal loops and lymphocyte slowing were rarely observed in the contralateral control microcirculation. Results suggest that structural adaptations in inflammatory microcirculation represented by focal topographic changes may contribute to regulation of tissue entry by recirculating lymphocytes.

Adjuvants, Immunologic↗
PubMed1975

[Histomorphology of the microcirculation of the skin in physiological and pathological processes].

On the base of skin histomorphological investigations of 985 deceased with different diseases age morphological pecularities in microcirculation were concluded to exist as well as changes depending on the duration and character of the pathological process. The involvement of a great number of vessels is an index for increased functional microcirculation requirements. The microcirculation character cannot be defined only by the morphological pecularities of single capillaries, by quantitative and qualitative changes in them. The capillary changes relfect only part of the microcirculation changes. All microcirculation peculiarities cannot be deciphered by the histomorphological method of the investigation but that method supplies valuable data that cannot be obtained by the other investigation methods. Three stages of changes in microcirculation are specified, being morphologically characterized. The changes in the microcirculation of the nail mantle skin are non-specific, functional, organic, reversible, non-reversible and usually compensated.

Adolescent↗
PubMedDate not supplied

Hemodynamic and hepatic microcirculational changes in endotoxemic rats treated with different NOS inhibitors.

BACKGROUND/AIMS: Severe septic shock may produce hypotension, which is due to the vasodilatational effect of nitric oxide. The effects of different nitric oxide synthase inhibitors on the hemodynamic and hepatic microcirculation of the endotoxemic rats were studied. METHODOLOGY: A prospective controlled study was performed. Eighteen Sprague-Dawley male rats (250-300 g) were anesthetized and studied. The rats were divided into three groups. The rats in group A (n = 6) were injected with lipopolysaccharide (50 mg/kg BW) and L-NAME (5 mg/kg BW). The rats in group B (n = 6) were injected with the same dose of lipopolysaccharide and aminoguanidine (400 mumole/kg BW). The rats in group C rats (n = 6) were injected with same dose of lipopolysaccharide and normal saline as a control. The rats were cannulated with femoral arterial, venous, and jugular venous catheters. Cardiac output was measured using a thermodilutional method, and liver sinusoidal microcirculation was measured with Laser Doppler Flowmetry. The cardiac output, stroke volume, heart rate, blood pressure, and microcirculational flux of the liver in the three groups were measured and compared at 0, 20, 40, 60 and 80 minutes after injection. RESULTS: The rats of group A showed significant decrease of their cardiac output, stroke volume and hepatic microcirculation after the drugs were infused though their blood pressure increased. The rats of group B showed decrease of their blood pressure and stroke volume initially, but no significant change of their cardiac output and hepatic microcirculation. At the 80th min, the rats of group B had the significantly highest cardiac output, stroke volume and hepatic microcirculation among three groups. CONCLUSIONS: The aminoguanidine prevents the hypotensive effect as well as L-NAME during severe sepsis, but it can maintain cardiac output, stroke volume and hepatic microcirculation better than L-NAME.

Animals↗
PubMed2003

[Measurement of microcirculation during experimental ureter implantation].

INTRODUCTION: Various types of ureter neoimplantation methods can be used in diseases that affect the distal part of the ureter. The most common techniques are the Cohen and the Politano. When the ureter is dilatated tapering of the enlarged ureter is necessary during neoimplantation using excisional or plication techniques. The aim of the study was to compare the effect of these different methods on the ureter tissue microcirculation in animal model and to answer the question which technique has better outcome. METHOD: The authors investigated tissue microcirculation patterns of ureter segments under surgical conditions employing Laser Doppler flowmetry in dogs. Different surgical procedures were compared in the function of tissue microcirculation as measured in the affected ureter segments. Measurements both in the intra- and postoperative periods were performed to compare different methods of ureter neoimplantation (Cohen vs. Politano-Leadbetter) and tapering (excisional technique, i.e. tailoring vs. plication of the lower ureter). The status of the ureter microcirculation was compared before and after catheterisation. 9 cases of Politano-Leadbetter and 9 cases of Cohen procedure as well as ureter tailoring in 7 and plication in 6 cases were performed in mongrel dogs. The microcirculation patterns of the ureter were detected intraoperatively and postoperatively using Laser Doppler Flowmetry device. The influence of catheter insertion on ureter microcirculation was examined in each case. RESULTS: Among the neoimplantation methods the Cohen procedure whereas among the tapering procedures the plication of the ureter were found to affect the least the microcirculation of the ureter tissue. The catheter insertion had significantly worsened the blood supply. CONCLUSION: Based on these results better outcome can be expected with the Cohen neoimplantation method and plication of ureter as compared with others.

Animals↗
PubMed1981

The emerging role of the microcirculation in clinical medicine.

Although research on microcirculation has expanded rapidly in the last 20 years, clinical evaluation of microcirculation, as an entity, has not achieved any status in the United States. Three aspects of microcirculation are presented, wherein clinical applications exist or on the verge of existing. Biomicroscopy is the direct observation of, and measurements within, the microcirculation is superficial areas of the body. Not only can the pattern of the microcirculation be examined and related to microcirculatory function but also the intravascular relationships among red cells, leukocytes, and platelets can be studied. Rheology includes measurement of the interactions among plasma and cellular elements during flow within the microcirculation. Unfortunately, rheologic factors are generally ignored in thinking about hemodynamics. The concept of the optimal hematocrit has great clinical relevance in both acute and chronic disease. Transvascular fluid and solute exchange can be evaluated in the body as a whole and in individual organs by relatively noninvasive techniques. Such evaluations provide useful information about the natural progress and the effect of treatment of a variety of serious diseases. Microcirculation, as an entity, is a quantitative science in its own right and ought to be actively applied in clinical medicine.

Biological Transport↗
PubMed1993

ACE-inhibitors and coronary microcirculation.

Arterial hypertension is the most frequent cause of a disturbance of coronary microcirculation. Inspite of having normal epicardial coronary arteries, patients with arterial hypertension often have symptoms of angina pectoris and a positive exercise tolerance test. The angina pectoris-symptoms in patients with arterial hypertension are due to functional and structural alterations of the coronary microcirculation. Consequently, an antihypertensive therapy should not only aim at lowering blood pressure and reversing myocardial hypertrophy, but also improve coronary microcirculation in order to avoid the consequences of chronic ischemia on the myocardium. Until now, only experimental studies have indicated that antihypertensive therapy can improve coronary flow reserve. To determine to what extent under clinical conditions coronary flow reserve can be improved, in hypertensive patients maximal coronary blood flow, minimal coronary resistance, and coronary reserve (Dipyridamol) were studied before and after a long-term antihypertensive treatment (9-12 months) with the ACE-inhibitor enalapril (10-20 mg/d). To assess the chronic effects rather than the acute effects of the antihypertensive pharmacon, the coronary microcirculation was studied after intermission of medical therapy for a period of 1 week. Along with a decrease in LV muscle mass by about 8%, coronary reserve was improved after enalapril by 48%. It is likely that the observed increase in coronary reserve is related to the reversal of structural vascular abnormalities at the level of the coronary microcirculation. Consequently, it seems that reparation of hypertensive remodeling of the coronary microcirculation can be induced by ACE-inhibitor therapy.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2005

The role of nitric oxide in the modulation of hepatic microcirculation and tissue oxygenation in an experimental model of hepatic steatosis.

BACKGROUND: Impairment of hepatic microcirculation in fatty liver has been assumed to reduce tolerance of the liver against ischemia-reperfusion injury. The present study was aimed to investigate the role of nitric oxide (NO) in the regulation of hepatic microcirculation and tissue oxygenation in hepatic steatosis. METHODS: Sprague-Dawley rats (200-250 g) were fed a 2% cholesterol diet (n = 12) to induce hepatic steatosis or normal diet (n = 12) served as controls for 12 weeks. Hepatic blood flow, microcirculation, tissue oxyhemoglobin (HbO2) and cytochrome c oxidase radox status (Cyt Ox) in response to intravenous bolus administrations of l-arginine (300 mg/kg) or l-NAME (20 mg/kg) were assessed. RESULTS: Animals which developed moderate hepatic steatosis showed significant increase in tissue level of total lipids. Portal blood flow and hepatic microcirculation were significantly reduced as compared to controls (5.7 +/- 0.9 vs. 9.7 +/- 0.9 ml/min, P = 0.003 and 114.5 +/- 9.5 vs. 167.3 +/- 10.0 flux unit, P = 0.003). l-Arginine improved hepatic arterial and portal blood flows as well as microcirculation in fatty livers (P < 0.05), while l-NAME significantly worsened these parameters (P < 0.05). Hepatic tissue HbO2 and Cyt Ox were improved both in fatty and control livers following l-arginine, while l-NAME resulted in decreased HbO2 and Cyt Ox although a transit increase in tissue oxygenation was observed in fatty livers. CONCLUSIONS: NO is involved in the modulation of hepatic microcirculatory perfusion and oxygenation in cholesterol-induced hepatic steatosis. NO metabolisms may be regulated as a potential therapeutic strategy for impaired microcirculation in hepatic steatosis.

Alanine Transaminase↗
PubMed2001

Visualization of rat pial microcirculation using the novel orthogonal polarized spectral (OPS) imaging after brain injury.

Recently, the novel optical system, orthogonal polarized spectral (OPS) imaging was developed to visualize microcirculation. Investigation of changes in microcirculation is essential for physiological, pathophysiological, and pharmacological studies. In the present study applicability of OPS imaging was assessed to study pial microcirculation in normal and traumatized rat brain. High quality images of rat pial microcirculation in normal and traumatized rats were generated with the OPS imaging, allowing to easily differentiate arterioles and venules with the dura remaining intact. In non-traumatized rats, mean vessel diameter of arterioles and venules of five different cortical regions was 19.1+/-2.7 and 22.2+/-1.4 microm, respectively. In the early phase following focal cortical contusion vessel diameter was significantly decreased in arterioles by 28% while diameter in venules was significantly increased by 27%. For technical reasons velocity in arterioles was not measurable. In venules, mean flow velocity of 0.68+/-0.08 mm/s was significantly decreased by 50% at 30 min after trauma. OPS imaging is an easy to use optical system allowing to generate high quality images and to reliably investigate pial microcirculation without having to remove the dura. This technique opens the possibility to perform longitudinal studies investigating changes in pial microcirculation.

Animals↗
PubMed1990

Protective effects of trifluoperazine on the microcirculation of cold-stored livers.

Previous studies have shown a protective effect of trifluoperazine (TFP), a calmodulin inhibitor, upon the microcirculation of cold-stored kidneys. The present study points to similar beneficial effects of TFP on the microcirculation of cold-stored livers; 25 canine livers were preserved for 24 hr with Euro-Collins' solution (EC) (n = 8), University of Wisconsin solution (UW) (n = 7), or UW + TFP (n = 10). The stored livers underwent heterotopic transplantation (HLTX); hepatic-artery and portal-vein pressure and flow were monitored; oxygen consumption and extraction were measured before HLTX and at 15-min intervals after reperfusion, for 1 hr. Mean hepatic-artery and portal-vein flow (HAF & PVF) prior to donor hepatectomy were 172 and 530 cc/min, respectively. Poor HAF and PVF occurred in EC-HLTX (mean 35, 175 cc/min, respectively). The damaged EC-flushed livers could not compensate to the decreased hepatic blood flow by increased oxygen extraction (oxygen consumption and extraction, 8.7 vol.% and 48%, respectively). Light and electron microscopy showed severe liver necrosis and periportal hemorrhages. Improved hepatic-artery and portal-vein flows were seen in UW HLTX (105 and 254 cc/min), and oxygen consumption and extraction were 16.4 vol.% and 66%, respectively. Liver biopsy taken just before reperfusion revealed well-preserved liver architecture. Liver biopsy obtained 1 hr after reperfusion revealed marked edema of the portal triad, sinusoid congestion, and hemorrhage. Electron-microscopy biopsies obtained during reperfusion at 15-min intervals revealed severe vasospasm of the terminal hepatic arterioles and progressive damage to the liver microcirculation. The addition of TFP to the UW-flush solution resulted in excellent protection of the liver microcirculation. Marked increase in hepatic-artery and portal-vein blood flow was noted after reperfusion (mean 167 and 421 cc/min, respectively (P 0.02 vs. UW: P 0.001 vs. EC). The recovery of metabolic activity was evident by the high oxygen consumption and extraction (25.8 vol.% and 80%, respectively). And serial liver biopsies obtained after reperfusion have shown excellent protection of liver architecture and the absence of hepatic arteriolar vasospasm. Taken together, these data suggest that the addition of TFP to the UW solution protects the liver microcirculation by rendering the hepatic microcirculation insensitive to vasospastic stimuli during reperfusion, thus permitting better metabolic recovery after transplantation.

Adenosine↗
PubMed2003

Noninvasive in vivo analysis of the human hepatic microcirculation using orthogonal polorization spectral imaging.

BACKGROUND: Analysis of hepatic microvascular perfusion in humans by direct imaging has been impossible so far. Orthogonal polarization spectral (OPS) imaging represents a new technology that combines simultaneous epi-illumination of the subject with linearly polarized light and noninvasive imaging of the microcirculation by reflectance spectrophotometry. The aim of this study was to evaluate the feasibility of studying the human hepatic microcirculation by OPS imaging in vivo and to define microcirculatory parameters for physiologic conditions. METHODS: The hepatic microcirculation was analyzed in four different regions of both liver lobes in 11 healthy individuals undergoing partial liver resection for living-donor liver transplantation. The optical probe was gently positioned on the liver surface and sequences of at least 20 sec per measurement were recorded by a charge-coupled device camera on videotape. Microhemodynamic parameters were quantified off-line by single-frame and frame-to-frame analysis using a computer-assisted image analysis system. RESULTS: OPS images of the hepatic microcirculation showed an acceptable quality with good resolution. Quantitative analysis revealed a sinusoidal red blood cell velocity of 0.97+/-0.43 mm/sec, a sinusoidal diameter of 8.8+/-0.9 microm, a sinusoidal volumetric blood flow of 58.2+/-9.6 pL/sec, an intersinusoidal distance of 22.6+/-2.5 microm, and a mean functional sinusoidal density of 391+/-30 cm-1. Apart from the sinusoidal red blood cell velocity, all data of the parameters studied matched the pattern of normal distribution. CONCLUSIONS: OPS imaging enabled for the first time direct in vivo visualization and quantification of the human hepatic microcirculation, providing significant insight into microvascular physiology of the human liver, to the extent that these data can be considered to represent physiologic values for human hepatic microcirculation.

Adult↗
PubMed2001

Posttreatment histology and microcirculation status of osteogenic sarcoma after a neoadjuvant chemo- and radiotherapy in combination with local electromagnetic hyperthermia.

BACKGROUND: Many biological attributes of tumors (including regional blood flow and microcirculation) can deteriorate the homogeneity of heat distribution and temperature elevation during hyperthermia. We analyzed the connection between the microcirculation status of osteogenic sarcomas and the posttreatment histology after neoadjuvant chemotherapy, irradiation and local hyperthermia. PATIENTS AND METHODS: 62 patients with histologically verified osteosarcoma (35 men, 27 women, age 9-53, average 21 years) were enrolled in the retrospective pathohistological study. 61 patients were evaluable. In 72.6% of cases the tumor was localized in bones forming knee joints. All patients received neoadjuvant treatment [6 hyperthermias (60 min, 42-45 degrees C), daunorubicin 30-50 mg/m(2), 6 infusions, adriamycin or cisplatin 30 mg/m(2) for 3 days or once 90 mg/m(2) monochemotherapy before the hyperthermic procedure; subsequently gamma-therapy, 20-36 Gy] followed by surgery. From archives, a control group was formed of 20 therapy-naive tumors. Resected tumors were histologically examined for assessment of spontaneous and therapeutically induced alterations. For analysis of the functionality status of microcirculation on histological cuts, 40 tumors (without selection) were investigated: 10 controls and 10 cases each with minimal, subtotal and total posttreatment alterations. RESULTS: Chemotherapy and radiotherapy in combination with local hyperthermia induced a distinct damage to osteosarcoma. In 39.3 and 35.7% of cases there was subtotal and total devitalization of tumor parenchyma, respectively. Thrombosis of magistral and middle vessels, stasis in the microcirculation tree (collapse), damage to intimal vessels and endothelial cells, and necrotic alterations of the vessel walls appeared predominantly in central areas of tumors. Tumors with minimal devitalization of the parenchyma had a share of nonfunctional vessels ranging from 10.6 to 61.7%, mean 29.7%. In tumors with subtotal necrosis, between 34.5 and 72.0% (mean 49.46%) of vessels were nonfunctional (stasis, thrombosis). In 10 cases with 100% necrosis of the osteosarcoma parenchyma, a mean of 56.05% of nonfunctional vessels was registered (12.3-83.0%). In the control group, between 2.85 and 73.4% (mean 21.69%) of vessels showed damage to the microcirculation. CONCLUSION: There is a direct correlation between deterioration of the microcirculation in osteosarcoma and thermo-radiochemotherapy- induced tissue alteration; the devitalization grade is directly proportional to the number of nonfunctional vessels in the tumor.

Adolescent↗
PubMed1997

Coronary microcirculation in health and disease. Summary of an NHLBI workshop.

This article summarizes a 2-day workshop on the coronary microcirculation held in Bethesda, Md, in September 1994 and sponsored by the National Heart, Lung, and Blood Institute of the National Institutes of Health. The workshop explored a variety of topics pertaining to coronary microvascular physiology and pathophysiology. The latest methodologies that are being used to investigate the coronary microvasculature, including endoscopic microscopy of the intramural coronary microvasculature and micro-x-ray computerized tomography, were discussed. The most recent advances in the regulation of the coronary microcirculation-for example, myogenic and flow-dependent responses, KATP channels, and regional heterogeneity-were reported. The workshop touched on the relation of the microcirculation to clinically important conditions and offered recommendations for future research in this important area. Comparisons are made to recent advances in the peripheral circulation and current gaps in our knowledge concerning the coronary microcirculation. In recent years, research on the coronary microcirculation has made substantial advances, in part as a result of investigations in the peripheral microcirculation but also because of the application of unique methodologies. This research is providing new ways to investigate abnormalities of myocardial perfusion, an area of inquiry that until recently has been limited to examination of coronary pressure-flow relationships.

Animals↗
PubMed2005

[The importance of microcirculation and tissue perfusion in hypertension].

The importance of abnormalities observed in the microcirculation of hypertensive subjects is being increasingly recognised. These microvascular changes may be central to the development of end-organ damage brought about by hypertension, including ischaemic heart disease. The primary function of the microcirculation is to supply oxygen and nutrients to myocardial tissue, and it also has an important role in regulating coronary blood flow. Some 70-90% of the overall peripheral resistance of the circulatory system arises at the level of the microcirculation. In hypertension, thickening of the microvascular walls occur, with narrowing of the lumen, so that eventually the vessel is functionally occluded. The result is a reduction in the number of arterioles or capillaries in a given vascular bed. Such changes have been seen in the structure and density of the microvasculature of heart muscle, the conjunctiva and retina, and in the kidneys. In hypertension a vicious circle occurs, with an increase in blood pressure producing a rise in resistance in the microcirculation, leading to further elevation of blood pressure. New techniques for exploring the coronary microcirculation have shown that microvascular damage results in reductions of coronary vasodilator reserve, an important predictor of clinical deterioration and death. With studies showing that impairment of microcirculation occurs early in patients with hypertension, there would seem to be a need for new therapeutic perspectives in hypertension, concentrating on preventing or reversing changes to the microvasculature of affected organs.

Blood Flow Velocity↗
PubMed2001

[Changes in serum levels of IGF-I and its binding proteins and their relation to microcirculation in obese patients].

The IGF-I system and its binding proteins participate in the pathogenesis of vascular affections under various pathological conditions. The mechanism and mode of its action were however not elucidated in details so far and views on its role are controversial. The objective of the study was to assess the relationship of this system and the blood flow in the microcirculation in obese patients. The authors examined 21 obese patients (BMI 39.7 +/- 7.3 kg/m2) and a group of healthy volunteers. They examined: serum concentrations of total IGF-I, free IGF-I, IGFBP-1,-2,-3, and -6, total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides as well as the intimomedial thickness of the common carotid arteries and parameters of blood flow in the microcirculation, evaluated by a laser-Doppler examination. In obese patients there were significantly lower serum concentrations of IGF-I and free-IGF I (p < 0.05) as compared with the control group. Comparison of the function of the microcirculation revealed in obese patients, as compared with the control group, a lower percentage increase of perfusion after occlusion (PORH%, p < 0.05) and after heating (TH%, p < 0.05) and a slower onset of thermal hyperaemia (THmax/t, p < 0.05). In the control group serum concentrations of free-IGF-I correlated inversely with the maximum perfusion after heat induced hyperaemia (THmax (r = -0.54, p < 0.02) and the rate of onset of hyperaemia after heating (THmax/t) (r = 0.51, p < 0.02). In the group of obese patients serum concentrations of free-IGF-I correlated inversely with the maximum perfusion after heat induced hyperaemia (THmax) (r = -0.55, p < 0.02), and IGFBP-3 concentrations correlated inversely with maximum hyperaemia after occlusion (PORGmax) (r = -0.57, p < 0.01). The results suggest that the function of the microcirculation in obese subjects is affected. The activity of the IGF-I system and its binding proteins is related to the affected function of the microcirculation and a negative part is played particularly by serum concentrations of free IGF-I. The negative effect of IGFBP-3 on the function of the microcirculation is surprising.

Blood Flow Velocity↗
PubMed2000

[A treatment combined Chinese with Western medicine for microcirculation diseases in tongue].

OBJECTIVE: Glossodynia is a common oral disease. The purpose of the investigation is to analyse the mechanism of microcirculation disorder in glossodynia, and find a new effective treatment. METHODS: 18 cases with microcirculation disorder in tongue were studied by histopathology, hemorrheology and nail microcirculation, treated by intravenous injection of angelica for promoting blood circulation and removing blood stasis. RESULTS: Hyper-viscosity of blood was found in this group of patients. Abnormal micro-vessels were observed in microcirculation examination, though vasculitis wasn't detected in tongue tissue. CONCLUSION: Microcirculation disorder may play an important role in the cause of glossodynia. For elderly patients, cardiovascular and mental diseases should be considered. According to the theory of the blood stasis in chinese medicine, these studies show that a treatment combined chinese with western medicine can be applied for the patients, and injection of angelica can improve microcirculation.

Aged↗
PubMedDate not supplied

The changes of hepatic sinusoidal microcirculation and effects of nitric oxide synthase inhibitor during sepsis.

BACKGROUND/AIMS: Sepsis may cause changes in liver blood flow, which may result in liver injury. Microcirculation in organ undergoes moderate alteration during sepsis or septic shock. The changes in hepatic microcirculation corresponding to liver functions and the effects of nitric oxide synthase inhibitor on the liver during sepsis were studied. METHODOLOGY: Sepsis was produced by CLP (cecal ligation and two-hole puncture). In part I, the leukocyte adherence, leukocyte rolling numbers, and velocity of sinusoidal microcirculation of liver were compared with in vivo microscopy among early septic, late septic and control rats. In part II, the rats were randomly divided into two groups after CLP procedure, group A was given L-NAME (NG-nitro-L-arginine-methylester hydrochloride), 10 mg/kg BW, and group B was given normal saline as a control. The hepatic microcirculation, measured with a Laser-Doppler Flowmeter, was performed at 0, 2, 4, 6, and 8 hours after the CLP procedure. Their liver functions were also examined and compared with the microcirculation. RESULTS: The results showed that the adherent and rolling numbers of leukocytes in the sinusoidal capillary significantly increased in early and late septic rats; and the centralized velocity of flow significantly decreased in late septic rats. For rats without L-NAME, their sinusoidal flux of the liver increased 2 and 4 hours after CLP, and then decreased gradually. Their GOT levels progressively increased after CLP, but the albumin levels decreased. For rats with L-NAME (group A), their sinusoidal flux levels at 2, 4 and 6 hours after CLP were significantly lower than those in rats without L-NAME (group B), but their GOT levels were higher since the 4th hour after CLP. CONCLUSIONS: Our conclusions are that hepatic microcirculation initially increased then decreased and the liver functions deteriorated gradually after sepsis was induced. These changes were aggravated when the nitric oxide synthesis was inhibited.

Animals↗