SEARCH · PubMed Health

Results for “endothelial dysfunction”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 1,279 records · Page 71Linked to original sources

PubMed2003

Blood cardioplegia supplementation with the sodium-hydrogen ion exchange inhibitor cariporide to attenuate infarct size and coronary artery endothelial dysfunction after severe regional ischemia in a canine model.

BACKGROUND: Activation of the sodium-hydrogen ion exchange mechanism results in accumulation of intracellular calcium through the sodium-calcium ion antiport mechanism. Administration of a sodium-hydrogen ion exchange inhibitor before or during ischemia attenuates myocardial ischemia and reperfusion injury. However, the cardioprotection exerted by sodium-hydrogen ion exchange inhibitors as adjuncts to cardioplegia without perioperative administration has not been tested in a model of surgical reperfusion of acute coronary occlusion with cardiopulmonary bypass. This study tested the hypothesis that sodium-hydrogen ion exchange inhibitor-supplemented blood cardioplegia would reduce postcardioplegia injury after severe regional ischemia. METHODS: In anesthetized open-chest dogs, the left anterior descending coronary artery was occluded for 75 minutes, after which total cardiopulmonary bypass was initiated. After crossclamping, cold (4 degrees C) antegrade blood cardioplegia was delivered every 20 minutes for a total of 60 minutes of cardioplegic arrest. In 8 dogs, the blood cardioplegic solution was unsupplemented (vehicle group), whereas in 8 others the solution was supplemented with the sodium-hydrogen ion exchange inhibitor cariporide (10 micro mol/L, cariporide group). RESULTS: In the in vitro studies, the direct effects of cariporide on neutrophil function were determined. Isolated canine neutrophils were stimulated by platelet activating factor. Cariporide attenuated superoxide anion production in a concentration-dependent manner, with no appreciable effect at 10 micro mol/L (the concentration used in blood cardioplegia) and a peak effect at 100 micro mol/L. In the in vivo cardiopulmonary bypass model, infarct size was significantly (P <.05) smaller in the cariporide group than in the vehicle group (22.4% +/- 3.5% vs 40.1% +/- 5.1% of area at risk), although there were no group differences in postischemic regional wall motion after 2 hours of reperfusion (0.1% +/- 0.9% vs -0.2% +/- 0.3% systolic shortening). Transmural myocardial edema in the area at risk was significantly decreased in the cariporide group (80.6% +/- 0.5%) relative to the vehicle group (83.1% +/- 0.6%). Myeloperoxidase activity in the area at risk, an index of neutrophil accumulation, was significantly lower in the cariporide group than in the vehicle group (4.7 +/- 0.9 absorbence units/[min. g tissue] vs 10.3 +/- 2.3 absorbence units/[min. g tissue]). In isolated postischemic left anterior descending coronary artery rings, maximum relaxation in response to the endothelium-dependent vasodilator acetylcholine was significantly greater in the cariporide group than in the vehicle group (77.5% +/- 7.4% vs 51.4% +/- 8.0%), whereas smooth muscle relaxation in response to nitroprusside was comparable between groups. CONCLUSION: In this canine model, supplementation of blood cardioplegia with cariporide, a sodium-hydrogen ion exchange inhibitor, reduced infarct size, attenuated neutrophil accumulation in the area at risk, and reduced postischemic coronary artery endothelial dysfunction without directly inhibiting neutrophil activity. Cariporide as an adjunct to blood cardioplegia without perioperative administration attenuated surgical ischemia-reperfusion injury in jeopardized myocardium.

Animals↗

PubMed2003

Patients with systemic lupus erythematosus show increased platelet activation and endothelial dysfunction induced by acute hyperhomocysteinemia.

OBJECTIVE: Hyperhomocysteinemia adversely affects the endothelium, although the exact mechanism is unclear. Systemic lupus erythematosus (SLE) is an inflammatory disease with a high atherothrombotic tendency. We examined whether acute hyperhomocysteinemia exacerbates endothelial and platelet dysfunction in patients with SLE. METHODS: Twelve SLE patients and 15 controls were recruited. Oral methionine was used to achieve acute hyperhomocysteinemia. Endothelial function was assessed by flow-mediated dilatation (FMD) of the brachial artery; also assessed were the levels of von Willebrand factor (vWF) and plasminogen activator inhibitor type 1 (PAI-1). Platelet activation was assessed by the levels of beta-thromboglobulin (beta-TG), fibrinogen binding, and P-selectin expression using flow cytometry. RESULTS: After oral methionine loading, vWF levels increased significantly, whereas FMD remained unchanged in both groups. PAI-1 increased significantly only in controls. Fibrinogen binding to platelets increased significantly only in SLE patients. Beta-TG remained unchanged in SLE patients but increased significantly in controls. Platelet P-selectin expression did not change in either group. CONCLUSION: These results suggest that the prothrombotic tendency after acute hyperhomocysteinemia is mediated by endothelial dysfunction and platelet activation in patients with SLE and healthy controls.

Acute Disease↗

PubMed2003

[Indicators of incipient atherosclerosis: demonstration of endothelial dysfunction with high-resolution ultrasound].

Endothelial function is thought to play a central role in the process of atherosclerosis, and in the pathogenesis of arterial hypertension and chronic heart failure. In the last decade a non-invasive ultrasound technique has been developed to measure endothelium-dependent vasodilation of the brachial artery which allows quantification of endothelial function. This method is based upon results in basic research, which show increased endothelial NO-production following the impact of shear forces on the endothelial surface. The resulting vasodilation can be quantified with high resolution ultrasound (7-13 MHz). The advantage of this technique is its non-invasive nature, which allows a risk-free use even in young individuals. Repeated measurements to control the success of medical intervention are also not problematic. Despite the possibility of widespread use because of its deceptively simple protocol, there are numerous factors affecting flow-mediated vascular reactivity. Details of the methods applied, variations in examination procedure, image acquisition, subjects preparation, equipment, training requirements and data interpretation are reviewed in this paper. Clinical studies of cardiovascular disease, risk factor profiles and the prognostic impact of measuring flow-mediated vasodilation are also discussed.

Arteriosclerosis↗

PubMed2001

Vitamin C improves endothelial dysfunction in renal allograft recipients.

BACKGROUND: Endothelial function is impaired in renal allograft recipients but the effects of antioxidant vitamin therapy on endothelial function in such patients is unknown. METHODS: Thirteen renal allograft recipients were randomized to vitamin C or placebo in a double blind cross-over study design. Flow-mediated endothelium-dependent dilation and glyceryltrinitrate-induced endothelium-independent dilation of the brachial artery were assessed before and 2 h after oral administration of 2 g vitamin C or placebo. RESULTS: Plasma vitamin C levels increased from 33.5+/-17.0 micromol/l to 98.8+/-60.2 micromol/l after treatment (P=0.0001). Endothelium-dependent dilation improved (from 1.6+/-2.6 to 4.5+/-2.5%) after vitamin C administration but was unchanged after placebo (1.9+/-1.5 to 1.8+/-2.5%; P=0.003 for vitamin C vs placebo). There was no significant change in endothelium-independent dilation in response to vitamin C. Vitamin C was also associated with a significant increase in the lag time in dilute serum oxidation (P=0.001). CONCLUSIONS: Vitamin C acutely improves flow-mediated, endothelium-dependent dilation and increases the resistance of lipoproteins in dilute serum to oxidation in renal transplant recipients.

Ascorbic Acid↗

PubMed1998

Endothelial dysfunction and inhibition of converting enzyme.

Endothelial cells control the tone of the underlying vascular smooth muscle by secreting vasodilator substances (prostacyclin, nitric oxide and endothelium-derived hyperpolarizing factor). These vasodilator substances also contribute to the antithrombogenicity of the normal endothelium, and inhibit cellular growth. In coronary vascular disease, the ability of the endothelium to secrete vasodilator substances is reduced, while the propensity to release endothelium-derived contracting factors is increased. In particular, the reduced release of nitric oxide in response to aggregating platelets, thrombin and circulating catecholamines favours the occurrence of thrombosis and vasospasm, and plays a key role in the initiation of the atherosclerotic process. From the therapeutic point of view, the best available way to enhance the release of endothelium-derived nitric oxide and hyperpolarizing factor is to inhibit converting enzyme. This will protect endogenous bradykinin from breakdown and prolong its action on endothelial receptors.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2002

The value of ECG and echocardiography during stress testing for identifying systemic endothelial dysfunction and epicardial artery stenosis.

BACKGROUND: In the stress imaging era, ECG positivity is regarded as a frequent source of false-positive responses. However, it is known that normal coronary arteries frequently coexist with abnormal endothelial function in patients with chest pain. AIM: To evaluate the anatomical coronary epicardial, and functional systemic endothelial determinants of wall motion and electrocardiographic responses during stress testing. METHOD: Sixty-eight in-hospital patients with chest pain syndrome, no previous myocardial infarction, and off nitrate therapy at the time of testing underwent, on different days, in random order and within 1 month: (1) stress ECG echo testing (with dipyridamole in 43, dobutamine in 3, and exercise in 22 patients); (2) coronary angiography; (3) endothelium-dependent, flow-mediated dilation of the brachial artery during reactive hyperaemia using high-resolution ultrasound. Criteria of positivity were: ST segment depression >0.1mm in the stress ECG; regional dysfunction >2 segments demonstrated by stress-echo; diameter reduction >50% on coronary angiography; and <5% flow-mediated dilation as revealed by endothelial function. RESULTS: Significant coronary artery disease was present in 39 patients, and was predicted on multivariate analysis by stress-induced wall motion abnormalities (OR=108.8; 95% CI=8.5-1,389.4, P=0.0003), but not by either ST segment depression (P=0.13; OR=0.47; 95% CI=0.7-1.3) or reduced flow-mediated dilation (P=0.81; OR=0.87; 95% CI=0.27-2.8). Abnormal flow-mediated dilation was present in 53 patients (78%), and was predicted by stress-induced ST segment depression (P=0.023; OR=6.2; 95% CI=1.3-30.5), but not by either stress echo positivity (P=0.66; OR=0.77; 95% CI=0.23 to 2.5) or angiographically assessed coronary artery disease. There was no correlation between flow-mediated dilation and extent of coronary artery disease as assessed by the angiographic Duke score (from 0=normal to 100=most severe disease): r=-0.13, P=0.91. CONCLUSION: Epicardial coronary artery anatomy affects wall motion abnormalities, and systemic endothelial dysfunction affects ST segment depression during stress. However, echocardiographic positivity is unrelated to endothelial dysfunction, and electrocardiographic positivity is an inaccurate predictor of coronary stenosis. An integration of ECG and functional markers is warranted in the stress testing lab.

Aged↗

PubMed1998

[Von Willebrand factor and pulmonary endothelial dysfunction. Prognostic implications].

PURPOSE: To analyze quantitative and structural changes in circulating von Willebrand factor (vWF) in 40 precapillary pulmonary hypertensive patients, as an attempt to identify possible correlations between endothelial cell dysfunction and patient short-term (one year) survival. METHODS: Plasma antigenic activity of vWF (vWF:Ag) was analyzed by immunoelectrophoresis. The relative concentration of vWF low molecular weight multimers (LMWM%) and the composition of vWF subunit were determined by densitometric analysis of Western blots. RESULTS: vWF:Ag was importantly increased in patients in comparison with normals (p < 0.001). Patients also had increased LMWM% (p < 0.001) and increased degradation of vWF main subunit (p < 0.05). At the beginning of the study, nonsurvivors (N = 11) had higher vWF:Ag (p < 0.001) and LMWM% (p < 0.005) values in comparison with survivors. LMWM% was selected by logistic regression analysis as a predictor of death during the first year of follow-up (p < 0.05). CONCLUSION: Marked changes in circulating vWF likely reflect extensive pulmonary vascular endothelial cell dysfunction and are associated with poor short-term prognosis in pulmonary hypertension.

Adolescent↗

PubMed1999

Endothelial dysfunction during acute methionine load in hyperhomocysteinaemic patients.

Hyperhomocysteinaemia has been associated with arterial and venous thrombosis possibly by causing damage to the endothelium. We hypothesised that an oral load in methionine, that increases plasma homocysteine, would also result in an increase in biological markers of endothelial or platelet dysfunction. Then we investigated two groups of patients with arterial or venous occlusive disease: 17 with hyperhomocysteinemia and 12 without hyperhomocysteinemia. We measured in both groups plasma soluble thrombomodulin, von Willebrand factor, P-selectin and tissue factor plasma inhibitor before and 6 hours after a load with 100 mg/kg oral methionine. Methionine load resulted in a significant increase in von Willebrand factor in both groups (P<0.02), suggesting that endothelial dysfunction occurs during the load.

Administration, Oral↗

PubMed1989

Features of endothelial dysfunction in early diabetic nephropathy.

The release of tissue plasminogen activator (tPA) by vascular endothelial cells during exercise was studied in forty men with insulin-dependent diabetes. Three groups, matched for age and diabetes duration, were defined as: group I (n = 19), normal urinary albumin excretion (less than 30 mg/24 h); group II (n = 11), incipient diabetic nephropathy (30-300 mg albumin excreted per 24 h); and group III (n = 10), clinical diabetic nephropathy (more than 300 mg albumin excreted per 24 h). Nine non-diabetic men served as controls. The rise in tPA antigen with exercise was similar in the controls and group I but significantly smaller in groups II and III (p less than 0.01). The albumin transcapillary escape rate was significantly higher in groups II and III than in group I and normal controls (p less than 0.01). The basal plasma level of von Willebrand factor was higher in groups III (p less than 0.01) and II (difference not significant, p = 0.06) than in group I and normal controls. These findings suggest that insulin-dependent diabetic patients with only slightly raised urinary albumin excretion have general endothelial cell dysfunction or damage. It is not yet clear whether these changes are important in the pathogenesis of thrombosis and atherosclerosis in these patients.

Adolescent↗

PubMed2004

Estrogen does not prevent endothelial dysfunction caused by cigarette smoking.

BACKGROUND: Estrogen favors endothelial function while acute tobacco use provokes dysfunction. Previous studies have not examined the effect of smoking one cigarette at different stages of the menstrual cycle. HYPOTHESIS: Favorable actions of estrogen on endothelial function are transitorily abolished by smoking one cigarette. METHODS: Brachial artery endothelium-dependent dilation was measured noninvasively before, 10 min, and 1 h after smoking in 17 healthy premenopausal women. Studies were done in the first 3 days (early stage) and repeated between Days 9 and 13 of the menstrual cycle (middle stage). Estradiol was measured after each study. RESULTS: At basal conditions, women in the middle stage of their cycles, when estradiol was 20 times higher than in the early stage, had significantly more endothelial-dependent brachial dilatation. No difference in the marked depression caused by cigarette smoking was found between the two stages. One h recuperation was complete in both phases. CONCLUSION: Cigarette smoking abolishes the protection of circulating estrogen on endothelial function.

Adult↗

PubMed2003

Matrix metalloprotease-9, placental syncytiotrophoblast and the endothelial dysfunction of pre-eclampsia.

The maternal syndrome of pre-eclampsia is caused by generalized maternal endothelial cell dysfunction, arising directly or indirectly from factors of placental origin. Syncytiotrophoblast membrane microvesicular particles are shed from the placental surface into maternal blood in increased amounts in pre-eclampsia and, in vitro, both inhibit endothelial cell proliferation and cause marked changes in the morphology of the cultured cell monolayers. Because there is evidence that proteolytic activation and degradation of the underlying matrix can cause the same morphological changes, we tested the hypothesis that proteases intrinsic to syncytiotrophoblast microvillous membranes (STBM) are the cause of the in vitro endothelial changes. Purified STBM were analysed by zymography and western blotting. Although we could confirm the presence of urokinase plasminogen activator (uPA) in STBM we could demonstrate no intrinsic activity presumably because of its association with the plasminogen activator inhibitor-2 (PAI-2) which is also a component of STBM. We detected gelatinase activity and showed that it was due to the matrix metalloproteinase-9 (MMP-9). Its presence was confirmed in this location by immunohistocytochemistry. Protease inhibitors caused a small reversal of the effects of STBM on morphology and no effect on inhibition of proliferation. We conclude that the effect of STBM on endothelial cells is unlikely to be caused by intrinsic proteases.

Adult↗

PubMed2004

Prognostic value of systemic endothelial dysfunction in patients with acute coronary syndromes: further evidence for the existence of the "vulnerable" patient.

BACKGROUND: Endothelial vasodilator dysfunction may serve as a marker integrating the vascular risk of an individual; however, whether systemic vasodilator function predicts disease progression and cardiovascular event rates in patients with manifest acute coronary syndromes (ACS) is unknown. METHODS AND RESULTS: In 198 patients with angiographically documented ACS, forearm blood flow (FBF) responses to acetylcholine (ACH; 10 to 50 microg/min) and sodium nitroprusside (SNP; 2 to 8 microg/min) were measured by venous occlusion plethysmography before hospital discharge within 5 days of an episode of an ACS. Cardiovascular events (cardiovascular death, myocardial infarction, and ischemic stroke) served as outcome variables over a mean follow-up period of 47.7+/-15.1 months. Patients who experienced cardiovascular events during follow-up (n=31) had a significantly reduced vasodilator response to ACH (P<0.05) and SNP (P<0.05). By multivariate analysis, vasodilator response to ACH and elevated troponin T serum levels were the only significant (P<0.05) independent predictors of a poor prognosis, even after adjustment for traditional cardiovascular risk factors, concurrent medication, invasive treatment strategy, and C-reactive protein serum levels. Recovery of endothelium-dependent vasoreactivity as assessed by repeated FBF assessment 8 weeks after the index measurement after the ACS predicted further event-free survival in a subset of 78 patients. CONCLUSIONS: Systemic endothelium-dependent vasoreactivity predicts recurrence of instability and cardiovascular event rates in patients with ACS. Furthermore, the recovery of systemic endothelial function is associated with event-free survival. Assessment of systemic vasoreactivity, measured by a minimally invasive test, provides important prognostic information in addition to that derived from traditional risk factor assessment in patients with ACS.

Acetylcholine↗

PubMed1996

Inhaled nitric oxide prevents pulmonary endothelial dysfunction after mesenteric ischemia-reperfusion.

This study examined the effect of inhaled nitric oxide (NO) on lung neutrophil accumulation and endothelial-dependent and -independent guanosine 3',5'-cyclic monophosphate (cGMP)-mediated mechanisms of pulmonary vasorelaxation after mesenteric ischemia-reperfusion (I/R) in mechanically ventilated rats. Inhaled NO (20 ppm) was administered in two protocols: 1) throughout mesenteric I/R and 2) during mesenteric reperfusion alone. Concentration-response curves were generated (10(-9) to 10(-8) M) for acetylcho-line (ACh), A23187, and sodium nitroprusside (SNP) in isolated pulmonary arterial rings preconstricted with phenylephrine. Lung neutrophil accumulation [myeloperoxidase assay (MPO)] was significantly increased from 2.4 +/- 0.2 units/g lung wt in controls to 10.3 +/- 0.4 after 1 h of superior mesenteric artery occlusion and 2 h of reperfusion. Lung MPO activity was not different from controls in rats receiving inhaled NO either 1) during mesenteric I/R or during mesenteric reperfusion alone. The concentration-response curves demonstrated significant impairment of pulmonary vasorelaxation by endothelial-dependent mechanisms (response to ACh and A23187) but not endothelial-independent pulmonary vasorelaxation (response to SNP) after mesenteric I/R. This pulmonary vasomotor dysfunction was prevented by administration of inhaled NO during either mesenteric I/R or during mesenteric reperfusion alone. We conclude that inhaled NO prevents lung neutrophil accumulation and pulmonary vascular endothelial dysfunction after mesenteric I/R.

Administration, Inhalation↗

PubMed2001

Endothelial dysfunction and denudation in rat aortic allografts.

Clinical evidence suggests that early endothelial cell (EC) dysfunction may predict the development of graft vascular disease. We wished to assess the early functional and morphological changes in the graft endothelium in a commonly used animal model of graft vascular disease, the rat aortic interposition allograft model. To assess graft EC function, regulation of vascular tone by ECs was monitored in aortic rings from grafts harvested at various times after transplantation (Tx). EC morphology was assessed by silver staining, which was followed by en face inspection of the luminal side of the grafts. Acetylcholine-induced EC-dependent vasorelaxation was reduced in allografts at post-Tx days 7 and 14, whereas in syngeneic grafts EC-dependent relaxation was unaffected at any time after Tx. In separate grafts collected at the same time points, massive leukocyte adhesion at post-Tx day 7 and EC denudation at days 14 and 28 were evident in allografts but not in syngeneic grafts. At post-Tx day 56 (a time at which vessel wall remodeling is pronounced in this model), an intact EC layer covered the grafts. EC dysfunction and morphological changes were prevented by immunosuppression of recipient rats with cyclosporine. Our study shows that Tx-induced EC dysfunction in rat aortic allografts can be observed within 1 week of Tx in rat aortic allografts and that this is occurring concomitantly with enhanced leukocyte adhesion to the graft ECs. These changes occur before any other morphological or functional changes described thus far in this model and appear to be immune-driven. Taken together, these results show that Tx-induced early EC dysfunction, as described in patients, may be studied in the model of rat aortic Tx.

Animals↗

PubMed2003

Elevated C-reactive protein levels are associated with endothelial dysfunction in chronic cocaine users.

OBJECTIVE: To examine the relationship of the serum C-reactive protein (CRP) and endothelial function and their associations with coronary artery calcification, lipid profile and cardiac changes. METHODS: The analyses for serum lipids and CRP, echocardiography, spiral computed tomography scans and endothelial function assay were performed in 53 participants with a history of chronic cocaine use. RESULTS: There were no statistically significant differences in demographic characteristics and drug use between CRP normal (<1.9 mg/l) and abnormal groups. The brachial artery diameter percentage changes in the third scan (immediately after deflation of cuff) and the fourth scan (90 s after deflation of cuff) were significantly associated with the CRP levels (the third: beta=-0.054, S.E.=0.027; P=0.028; the fourth: beta=-0.065, S.E.=0.026; P=0.016). The multiple regression models showed that CRP was the only significant predictor of artery diameter changes (%) in these two scans. The CRP abnormal group had more coronary artery calcification (calcium scores >5, 16.7 vs. 0%; P=0.036) and more cardiac diastolic dysfunction expressed as deceleration time >240 ms (16.7 vs. 0%; P=0.036). CONCLUSIONS: Elevated serum CRP levels are associated with endothelial dysfunction, coronary artery calcification and cardiac diastolic dysfunction in chronic cocaine users.

Adult↗

PubMed2005

Targeted ultrasound contrast agents: in vitro assessment of endothelial dysfunction and multi-targeting to ICAM-1 and sialyl Lewisx.

An ultrasound-based molecular imaging technique capable of detecting endothelial cell markers of inflammation may allow early, non-invasive assessment of vascular disease. Clinical application of targeted, acoustically-active microbubbles requires optimization of microbubble-endothelial adhesion strength to maximize image signal-to-noise ratio, as well as the ability to discern the degree of inflammation along a continuum of dysfunction. Accordingly, we hypothesized that adhesion of intercellular adhesion molecule-1 (ICAM-1)-targeted microbubbles is dependent on the degree of endothelial inflammation, and that microbubbles multi-targeted to both ICAM-1 (via anti-ICAM-1 antibodies) and selectins (via sialyl Lewisx) demonstrate greater adhesion strength than microbubbles targeted to either inflammatory marker alone. In a radial flow chamber, microbubbles were perfused across endothelial cells activated with interleukin-1beta to four different levels of inflammation, as assessed by quantitative ICAM-1 expression. ICAM-1-targeted microbubble adhesion strength increased with increasing degree of inflammation, with a relationship that was both positive and linear (r > 0.99). Microbubble adhesion strength was significantly higher for the multi-targeted microbubbles than either of the single-targeted microbubbles. These data thus demonstrate that multi-targeting of contrast microbubbles may offer improved adhesion characteristics, allowing for greater sensitivity to inflammation. Furthermore, the adhesion strength of targeted microbubbles is linearly dependent on the degree of inflammation, suggesting that targeted ultrasound imaging may offer differentiation between various degrees of endothelial dysfunction, and thus detect not only the presence, but also the severity of inflammatory disease processes.

Biomarkers↗

PubMed2001

Transplantation-induced endothelial dysfunction as studied in rat aorta allografts.

BACKGROUND: Clinical evidence indicates that vascular endothelial cell (EC) dysfunction occurs early after transplantation (Tx) and initiates chronic graft vasculopathy. This study explored this phenomenon in rat aorta Tx using the stringent Dark Agouti (DA)-to-Lewis (LEW) and the weak Fischer 344 (F344)-to-LEW strain combinations. METHODS: Donor abdominal aortae were orthotopically grafted into LEW rats. At post-Tx days 7, 14, 28, and 56, grafts were collected to assess changes in EC morphology (en face silver staining) and EC function, i.e., vasodilatory response to acetylcholine (ACH) after phenylephrine (PHE) precontraction; changes in vascular smooth muscle cell (VSMC) alpha-actin (western blotting), degree of apoptosis (caspase-3 activity), and morphology. RESULTS: In DA allografts, VSMC and EC dysfunctions developed concomitantly and were completed at 14 days post-Tx, most likely due to the EC and alpha-actin-positive VSMC loss. Meanwhile, allografts revealed markedly increased caspase-3 activity. Neointima formation, restricted to the edges of allografts at day 28, covered the entire allografts by day 56 post-Tx. In F344-allografts, VSMC function was maintained up to day 14 post-Tx, whereas ACH-induced relaxation was reduced by 50% at day 7 and abolished at day 14. EC denudation was not seen up to 56 days post-Tx, despite prominent leukocyte adhesion. Neointima formation was not detected at day 28 post-Tx but appeared along the entire allografts at day 56 post-Tx. CONCLUSIONS: These results confirm that Tx-induced EC dysfunction precedes the development of vasculopathy in rat aorta allografts and suggest that this early phenomenon can be best studied in the F344-to-LEW strain combination.

Actins↗

PubMed2004

NO bioavailability, endothelial dysfunction, and acute renal failure: new insights into pathophysiology.

This brief overview sketches current evidence of imbalance between inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS), role of oxidant stress, and generation of peroxynitrite in the pathophysiology of acute ischemic renal injury. The development of endothelial cell dysfunction at early stages of experimental acute renal ischemia is the focus of the review, with the results of recent studies on amelioration of renal injury by the infused endothelial cells engrafting in the renal microcirculation. Finally, this article provides some future perspectives on the potential usefulness of endothelial progenitor cells in the prevention and treatment of acute renal failure.

Acute Kidney Injury↗