Objective: Pulmonary embolism (PE) can cause intracardiac hemolysis and increased plasma hemoglobin and arginase-1, which can worsen pulmonary vasoconstriction. We test the hypothesis that patients with PE that causes tricuspid regurgitation (TR), indicative of higher pulmonary arterial pressures, have decreased leukocyte expression of hmox-1 compared with patients with PE and no TR and patients without PE.Design: Prospective, noninterventional study.Patients: Normotensive patients with suspected PE (n = 87) who underwent CT pulmonary angiography and transthoracic Doppler-echocardiography.Measurements: Significant TR was defined as a jet velocity >2.7 m/s. Leukocyte expression of hmox-1, haptoglobin, haptoglobin related gene, the haptoglobin receptor, CD163 and cox-2 genes were assessed by quantitative rtPCR, and the hmox-1 promoter was examined for the -413 A -> T SNP and GT repeat polymorphisms.Results: Of the 44 (50%) with PE+, 22 had TR+, and their mean pulmonary vascular occlusion (39 +/- 32%) did not differ significantly from patients who were TR-(28 +/- 26%, P = 0.15). Patients with PE+ and TR+ had significantly lower expression of hmox-1 and haptoglobin genes than patients without PE+ and no TR. Expression of hmox-1 varied inversely with TR velocity (r(2) = 0.45, P < 0.001) for PE+ (n = 22) but not patients without PE. Hmox-1 expression did not vary significantly with genotype. Cox-2 did not differ between groups and had no correlation with TR.Conclusions: Severity of TR varied inversely with hmox-1 expression, suggesting that hmox-1 expression affects pulmonary vascular reactivity after PE. (C) 2015 Elsevier Ltd. All rights reserved.

IntroductionThe objective of the study is to determine if changes in platelet mitochondrial function in patients with sepsis are present early after presentation and the association of these changes with clinical outcomes and systemic metabolic function.Materials and methodsThis is a prospective observational cohort study of a convenience sample of patients with severe sepsis. Mitochondrial function of intact, nonpermeabilized platelets suspended in their own plasma was estimated using high-resolution respirometry. Unstimulated basal respiration, oligomycin-induced state 4, and maximal respiratory rate after serial titrations of carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone were measured. Organ failure was estimated using Sequential Organ Failure Assessment score, and patients were followed up until 28 days to determine survival. Lactate levels were measured in all patients, and a subset of patients had lactate/pyruvate (L/P) ratios measured.ResultsTwenty-eight patients were enrolled, 21 of whom survived. Initial Sequential Organ Failure Assessment score and lactate levels were 8.5 (interquartile range [IQR], 6-10) and 2.3 (IQR, 1.2-3.5) respectively, whereas the median L/P ratio was 23.4 (IQR, 15.2-38). Basal and maximal respiratory rates were significantly higher among nonsurvivors compared to survivors (P = .02 and P = .04), whereas oligomycin-induced state 4 respiration was not statistically different between groups (P = .15). We found a significant association between maximal respiration and organ failure (P = .03) and both basal and maximal rates with initial lactate level (P = .04, P = .02), but not with L/P ratio.ConclusionsDifferences in platelet mitochondrial function between survivors and nonsurvivors are present very early in the hospital course and are associated with organ failure and lactate.

To the Editor: Measurements from humans and animal models with pulmonary embolism (PE) have demonstrated increases in multiple vasoconstrictive molecules, including prostaglandins, platelet-activating factor and leukotrienes [1]. Nitric oxide (NO), produced tonically by vascular endothelial nitric oxide synthase (eNOS), plays a pivotal role in maintaining a normal pulmonary vascular resistance under these conditions [2]. These facts underlie the construct hypothesis that in different subjects, PE can obstruct the same degree of pulmonary vasculature but manifest widely different pulmonary arterial resistances. Preliminary evidence from animal models and humans suggests that acute PE is associated with intravascular haemolysis, related to the severity of PE [3–8]. Intravascular haemolysis liberates haemoglobin and diffusible haem, both of which directly bind NO. Ruptured erythrocytes also release large amounts of the enzyme arginase-1, which cleaves the eNOS substrate l-arginine, producing urea and l-ornithine. We hypothesised that patients with acute PE that causes significant tricuspid regurgitation (TR) will have acutely increased plasma concentrations of arginase-1, decreased l-arginine and increased asymmetric dimethylarginine (aDMA) compared with patients who have mild PE without TR as well as patients without PE. This was a secondary analysis of a four-centre prospective study of diagnostic accuracy conducted in patients with suspected PE (www.clinicaltrials.gov identifier NCT00368836) [9]. The enrolment and diagnostic criteria have been described previously [9]. Acute PE was considered present if two independent board-certified radiologists interpreted a filling defect consistent with acute PE on computed tomographic pulmonary angiography. Echocardiography was performed using techniques as previously described, …

Back pain and intervertebral disc degeneration have a growing socioeconomic healthcare impact. Information on mitochondrial function in human intervertebral disc cells, however, is surprisingly sparse. We assessed mitochondrial bioenergetics, mass, and ultrastructure in annulus cells cultured from human discs of varying degenerative stages. Citrate synthase activity (reflecting mitochondrial mass) declined significantly with increasing Thompson grade (p<0.0001). Both mitochondrial (p=0.009) and non-mitochondrial (p=0.0029) respiration showed significant changes with increasing stages of disc degeneration. No significant relationships were found for the association of respiration data with herniated or non-herniated status, or with subject age. Examination of mitochondrial ultrastructure in cultured annulus cells revealed unusual features which included mitochondrial inclusion bodies, poorly defined cristae and dark staining. Findings reported here are novel and document biochemical, metabolic, and morphologic abnormalities in mitochondria in cells from more degenerated annulus cells. Data suggest that the disc degenerative, not age, is a major factor associated with mitochondrial impairment, and also implicate oxidative stress, driven by mitochondrial dysfunction, as a major component within the degenerating disc. Findings have relevance to advancements in cell-based therapies to treat disc degeneration. (c) 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1270-1275, 2013

OBJECTIVES:Inducing therapeutic hypothermia using chilled saline in resuscitated cardiac arrest patients has been shown to be feasible and effective. Limited research exists assessing the efficiency of this cooling method. The objective of this study was to assess the change in temperature of 4°C saline upon exiting an infusion set in the laboratory setting while varying conditions of fluid delivery.METHODS:Efficiency was studied by assessing change in fluid temperature (°C) during the infusion under four laboratory conditions. Each condition was performed four times using 1-L bags of normal saline. Fluid was infused into a 1000-mL beaker through 10 gtt/mL tubing. Flow rate was controlled using a tubing clamp and in-line transducer with a flow meter, while temperature was continuously monitored in a side port at the terminal end of the intravenous (IV) tubing using a digital thermometer. The four conditions included different insulation methods. Descriptive statistics and analysis of variance were performed to assess changes in fluid temperature.RESULTS:The mean (±SD) fluid temperature at time 0 was 3.2°C (95% confidence interval [CI] = 3.0 to 3.4 °C) with no significant difference in starting temperature between groups (p = 0.45). When flow rate was constant, it was determined that fluid temperatures were significantly cooler when infused using a chilled, gel-filled sleeve around the saline bag (p < 0.006).CONCLUSIONS:In a laboratory setting, the most efficient method of infusing cold fluid appears to be a method that both keeps the bag of fluid insulated and infused at a faster rate.

Introduction Microparticles (MPs) are small fragments of apoptotic or activated cells that may contribute to pathological processes in cardiovascular diseases. In studies of MPs in clinical cohorts, it is unclear if observed changes in MP composition are a cause or a result of the cardiovascular disease being studied. The present studies employed a well-characterized rat model of experimental pulmonary embolism (PE) to determine if there were changes in MP characteristics as a result of pulmonary vascular occlusion. Methods PE was produced by infusing 25 μm polystyrene microspheres into the jugular vein of anesthetized rats. MPs were isolated by differential centrifugation of arterial blood 18 hr after PE. Proteins were separated by 1D gel electrophoresis and identified from tryptic digests by ultraperformance liquid chromatography (UPLC) coupled with tandem mass spectrometry. Statistical analysis was conducted using the Power Law Global Error Model (PLGEM). Changes in two proteins were confirmed by Western blot. Results Experimental PE produced pulmonary hypertension, mild systemic hypotension, hypoxia, hypercapnia and lactic acidosis. MPs showed significant elevation in proteins involved in clotting (fibronectin precursor, fibrinogen alpha, beta and gamma and von Willebrand factor) and several macroglobulin proteins, such as alpha-2-macroglobulin precursor compared with vehicle-treated control rats. Consistent with recent observations of hemolysis in PE, haptoglobin precursor protein, a major protein of hemoglobin clearance, decreased significantly in the PE animals. Plasma d-Dimer concentrations were significantly elevated, indicating that experimental PE produced a pro-coagulant state. Conclusions These findings suggest that experimental PE produced significant, changes in MP characteristics to a prothrombotic phenotype.

Pulmonary embolism (PE) increases pulmonary vascular resistance, causing right ventricular (RV) dysfunction, and poor clinical outcome. Present studies test if the soluble guanylate cyclase stimulator BAY 41-8543 reduces pulmonary vascular resistance and protects RV function. Experimental PE was induced in anesthetized, male Sprague-Dawley rats by infusing 25 μm polystyrene microspheres (1.95 million/100 g body wt, right jugular vein) producing moderate PE. Pulmonary artery vascular resistance, estimated as RVPSP/CO, increased 3-fold after 5 h of PE. Treatment with BAY 41-8543 (50 μg/kg, I.V.; given at the time of PE induction) normalized this index by reducing RVPSP and markedly increasing CO, via preservation of heart rate and stroke volume. Ex vivo RV heart function showed minimal changes at 5 h of PE, but decreased significantly after 18 h of PE, including peak systolic pressure (PSP, Control 39 ± 1 mmHg vs. 19 ± 3 PE), +dP/dt (1192 ± 93 mmHg/s vs. 444 ± 64) and -dP/dt (-576 ± 60 mmHg/s vs. -278 ± 40). BAY 41-8543 significantly improved all three indices of RV heart function (PSP 35 ± 3.5, +dP/dt 1129 ± 100, -dP/dt -568 ± 87). Experimental PE produced increased PVR and RV dysfunction, which were ameliorated by treatment with BAY 41-8543. Thus, there is vasodilator reserve in this model of experimental PE that can be exploited to reduce the stress upon the heart and preserve RV contractile function.

Right ventricular (RV) dysfunction contributes to poor clinical prognosis after pulmonary embolism (PE). The present studies evaluate the effects of angiotensin (1-7) (ANG (1-7)) upon RV function during experimental PE in rats. Circulating ANG II increased 8-fold 6 hr after PE (47±13 PE vs. 6±3 pg/mL, control, p<0.05). ACE2 protein was uniformly localized in the RV myocardium of control rats, but showed a patchy distribution with some cells devoid of stain after 6 or 18 hr of PE. RV function decreased 18 hr after PE compared with control treated animals (19±4 vs. 41±1 mmHg, respectively, p<0.05; 669±98 vs. 1354±77 mmHg/sec, respectively, p<0.05), while left ventricular function (LV) was not significantly changed. Animals treated with ANG (1-7) during PE showed improved RV +dP/dt and peak systolic pressure development to values not significantly different from control animals. Protection of RV function by ANG (1-7) was associated with improved arterial blood sO2, base excess and pH. Supplemental delivery of ANG (1-7) reduced the development of RV dysfunction, suggesting a novel approach to protecting RV function in the setting of acute experimental PE.

BACKGROUND CONTEXT:Mitochondrial dysfunction is recognized during cell senescence and apoptosis, two important components of human disc aging/degeneration. We hypothesize that mitochondrial dysfunction is present in the degenerating and senescent annulus cells. The objective of the present study was to analyze gene expression profiles related to mitochondrial function in vivo. PURPOSE:This study had two objectives in the analysis of gene expression patterns related to mitochondria in the human annulus: First, to assess human annulus cells in a genome-wide microarray analysis approach to evaluate mitochondrial gene expression in annulus tissue from degenerated compared with healthier discs. Second, to use laser capture microdissection (LCM) to selectively isolate senescent versus nonsenescent annulus cells to evaluate their mitochondrial gene expression patterns. STUDY DESIGN:Following approval by our Human Subjects Institutional Review Board, annulus cells from 20 human lumbar discs were analyzed for gene groups related to mitochondrial function; a subset was also analyzed, which focused on senescent versus nonsenescent annulus cells in a study of annulus cells from 10 lumbar discs. PATIENT SAMPLE:Human annulus tissue was used in molecular studies following institutional review board approval. OUTCOME MEASURES:Gene expression levels identified with microarray analyses were statistically evaluated using GeneSifter Web-based software (VizX Labs, Seattle, WA, USA). METHODS:Human annulus specimens were assessed for gene expression related to mitochondrial function. Approaches used whole annulus tissue and senescent or nonsenescent annulus cells selectively harvested using LCM. Microarray data were analyzed using gene ontology searches and GeneSifter Web-based software. RESULTS:Analysis of annulus cells compared mitochondrial gene expression patterns in annulus cells from more degenerated discs with patterns in annulus cells derived from healthier discs. Important findings included significant upregulation of p53 and several proapoptotic genes (including apoptosis-inducing factor, mitochondrion-associated 1, BCL2-like 11 [an apoptosis facilitator]; caspase 7 apoptosis-related cysteine peptidase; proteasome 26S subunit nonadenosine triphosphatase 10, programmed cell death 6, and reticulon 3). Methionine sulfoxide reductase (Msr), a repair enzyme that reduces methionine sulfoxide residues in proteins damaged by oxidation, was also significantly upregulated (2.02-fold increase). The gene "membrane-associated ring finger (C3HC4) 5" was significantly upregulated and relevant because it is believed to play a role in preventing cell senescence acting to regulate mitochondrial quality control. Nitric oxide synthase 3 (endothelial nitric oxide synthase [eNOS]) showed a 5.9-fold downregulation in more degenerated versus healthier annulus cells. In LCM-harvested senescent cells, Msr was significantly downregulated in senescent versus nonsenescent cells, a finding previously recognized in other types of senescent cells. CONCLUSIONS:Novel data showed that significant gene expression patterns are present in the human annulus related to mitochondrial dysfunction; changes were identified in important genes involving apoptosis, eNOS and Msr expressions, and solute carrier genes. Because current research efforts are focusing on bioactive compounds for mitochondria, we suggest that future biologic cell-based therapies for annulus degeneration should also consider mitochondrial-focused therapies.

Objectives:Pulmonary embolism causes pulmonary hypertension by mechanical obstruction and vasoconstriction. Therapeutic potential of pharmacologic dilation of unblocked vessels has received limited attention. We tested pulmonary vasodilator reserve using a soluble guanylate cyclase stimulator, BAY 41-8543. Design:Controlled animal study. Setting:Medical center research laboratory. Subjects:Male Sprague-Dawley rats. Interventions:Pulmonary embolism was induced by infusing 25-&mgr;m plastic microspheres in the right jugular vein, producing mild or moderate pulmonary hypertension. Control animals with no pulmonary embolism received suspension medium for microspheres. Measurements and Main Results:Mild pulmonary embolism increased right ventricular peak systolic pressure (from 28 to 38 mm Hg) and decreased cardiac output (from 46 to 34 mL/min) with no change in mean arterial pressure. Infusion of BAY 41-8543 (50–200 &mgr;g/kg) decreased right ventricular peak systolic pressure. Five hrs moderate pulmonary embolism increased right ventricular peak systolic pressure (from 28 to 47 mm Hg) and decreased cardiac output (from 48 to 27 mL/min), causing right ventricular peak systolic pressure/cardiac output to increase from 0.6 control with no pulmonary embolism to 1.8 mm Hg/mL/min in 5-hr moderate pulmonary embolism + solvent for BAY 41-8543. Treatment of 5-hr moderate pulmonary embolism with BAY 41-8543 (50 &mgr;g/kg) caused a 2.2-fold increase in cardiac output (59 mL/min) with a 46% reduction in right ventricular peak systolic pressure (38 mm Hg), suggesting significant pulmonary vasodilation. Moderate pulmonary embolism decreased arterial sO2 (from 83% to 71%) and increased lactate (from 0.5 to 2.3 mmol/L). Treatment with BAY 41-8543 normalized sO2 and lactate. Hemolysis occurred during moderate experimental pulmonary embolism (60-fold increase in plasma hemoglobin). Treatment with BAY 41-8543 reduced free plasma hemoglobin content by 80%. Conclusions:In the setting of moderate impervious pulmonary embolism, treatment with a guanylate cyclase stimulator normalized pulmonary hemodynamics, reduced hemolysis, and improved oxygenation. These data support the hypothesis that pharmacologic dilation of nonobstructed pulmonary vasculature can effectively treat acute pulmonary hypertension from pulmonary embolism.

Pulmonary embolism (PE) causes pulmonary hypertension by mechanical obstruction and constriction of non-obstructed vasculature. We tested if experimental PE impairs pulmonary vascular endothelium-dependent dilation via activation of arginase II. Experimental PE was induced in male Sprague-Dawley rats by infusing 25 μm microspheres in the right jugular vein, producing moderate pulmonary hypertension. Shams received vehicle injection. Pulmonary arterial rings were isolated after 18 h and isometric tensions were determined. Dilations were induced with acetylcholine, calcium ionophore A23187 or nitroglycerin (NTG) in pre-contracted rings (phenylephrine). Protein expression was assessed by Western blot and immunohistochemistry. Arginase activity was inhibited by intravenous infusion of N(w)-hydroxy-nor-l-arginine (nor-NOHA). l-Arginine supplementation was also given. Endothelium-dependent dilation responses were significantly reduced in PE vs. vehicle-treated animals (ACh: 50 ± 9% vs. 93 ± 3%; A23187: 19 ± 7% vs. 85 ± 7%, p < 0.05), while endothelium-independent dilations (NTG) were unchanged. Endothelial nitric oxide synthase (eNOS) protein content was unchanged by PE. Expression of arginase II increased 4.5-fold and immunohistochemistry revealed increased arginase II staining. Nor-NOHA treatment and l-arginine supplementation significantly improved pulmonary artery ring endothelium-dependent dilation in PE (ACh: 58 ± 6% PE, 88 ± 6% PE + nor-NOHA, 84 ± 4% PE + l-arginine). Experimental PE impairs endothelium-dependent pulmonary artery dilation, while endothelium-independent dilation remains unchanged. The data support the conclusion that up-regulation of arginase II protein expression contributes to pulmonary artery endothelial dysfunction in this model of experimental PE.

The experiments test if experimental PE causes red blood cell hemolysis, arginase release and depletion of L-arginine and determine if arginase inhibition preserves L-arginine and improves pulmonary hemodynamics during PE. Experimental PE was induced in male Sprague-Dawley rats by infusing 25 mu m microspheres (1.8 million/100 g body wt) in the jugular vein, producing moderate pulmonary hypertension. Pulmonary vascular resistance was estimated from the quotient of the right ventricular peak systolic pressure/cardiac output. Arterial plasma hemoglobin (ELISA), arginase activity (colorimetric assay) and L-arginine (high performance liquid chromatography) were determined. Arginase activity was inhibited by infusion of N-omega-hydroxy-nor-L-arginine (nor-NOHA, 400 mg/kg body wt, iv.). Values are means +/- se. Five hours of PE caused red blood cell hemolysis (15-fold increase in plasma hemoglobin) and release of arginase activity (2.7-fold increase). Plasma L-arginine concentration decreased significantly from 250 +/- 20.6 to 118 +/- 6.0 mu mol/L (Control vs. PE) and estimated pulmonary vascular resistance increased 3-fold. Treatment with nor-NOHA prevented the depletion of plasma L-arginine (229 +/- 15 mu mol/L) and reduced the rise in pulmonary vascular resistance by 40%. In conclusion, experimental PE causes hemolysis. release of arginase activity, depletion of plasma L-arginine and increased estimated pulmonary vascular resistance. Inhibition of arginase activity preserves plasma L-arginine levels and improves estimated resistance, suggesting that the release of arginase during hemolysis contributes to the rise in estimated pulmonary resistance during experimental PE. (C) 2011 Elsevier Ltd. All rights reserved.

Background Experimental models of pulmonary embolism (PE) that produce pulmonary hypertension (PH) employ many different methods of inducing acute pulmonary occlusion. Many of these models induce PE with intravenous injection of exogenous impervious objects that may not completely reproduce the physiological properties of autologous thromboembolism. Current literature lacks a simple, well-described rat model of autlogous PE. Objective: Test if moderate-severity autologous PE in Sprague-Dawley (SD) and Copenhagen (Cop) rats can produce persistent PH. Methods blood was withdrawn from the jugular vein, treated with thrombin-Ca ++ and re-injected following pretreatment with tranexamic acid. Hemodynamic values, clot weights and biochemical measurements were performed at 1 and 5 days. Results Infusion of clot significantly increased the right ventricular peak systolic pressure to 45-55 mm Hg, followed by normalization within 24 hours in SD rats, and within 5 days in COP rats. Clot lysis was 95% (24 hours) and 97% (5 days) in SD rats and was significantly lower in COP rats (70%, 24 hours; 87% 5 days). Plasma D-dimer was elevated in surgical sham animals and was further increased 8 hours after pulmonary embolism. Neither strain showed a significant increase in bronchoalveolar chemotactic activity, myeloperoxidase activity, leukocyte infiltration, or chemokine accumulation, indicating that there was no significant pulmonary inflammation. Conclusions Both SD and COP rats exhibited near complete fibrinolysis of autologous clot PE within 5 days. Neither strain developed persistent PH. Experimental models of PE designed to induce sustained PH and a robust inflammatory response appear to require significant, persistent pulmonary vascular occlusion.

Background: The right ventricle normally operates as a low pressure, high-flow pump connected to a high-capacitance pulmonary vascular circuit. Morbidity and mortality in humans with pulmonary hypertension (PH) from any cause is increased in the presence of right ventricular (RV) dysfunction, but the differences in pathology of RV dysfunction in chronic versus acute occlusive PH are not widely recognized.Methods and Results: Chronic PH that develops over weeks to months leads to RV concentric hypertrophy without inflammation that may progress slowly to RV failure. In contrast, pulmonary embolism (PE) results in an abrupt vascular occlusion leading to increased pulmonary artery pressure within minutes to hours that causes immediate deformation of the RV. RV injury is secondary to mechanical stretch, shear force, and ischemia that together provoke a cytokine and chemokine-mediated inflammatory phenotype that amplifies injury.Conclusions: This review will briefly describe causes of pulmonary embolism and chronic PH, models of experimental study, and pulmonary vascular changes, and will focus on mechanisms of right ventricular dysfunction, contrasting mechanisms of RV adaptation and injury in these 2 settings. (J Cardiac Fail 2010;16:250-259)

Moderate to severe pulmonary embolism (PE) can cause pulmonary arterial hypertension and right ventricular (RV) heart damage. Previous studies from our laboratory indicate that the basal outflow tract of the RV is injured and has acute inflammation followed by tissue remodeling while the apex appears normal. The present studies examine transcription responses to chronic PE in RV apex and outflow tracts using DNA microarrays to identify transcription responses by region. Changes predominated in the RV outflow tract (8,575 genes showed >/=1.5-fold expression change). Gene ontology and KEGG analyses indicated a significant decrease in genes involved in cellular respiration and energy metabolism and increases in inflammatory cell adhesion molecules and extracellular matrix proteins. Signal pathways for wound healing such as fibroblast growth factor, collagen synthesis, and CCN proteins (named for the first three members of the family: cysteine-rich protein 61, connective tissue growth factor, and nephroblastoma overexpressed gene) were strongly upregulated. In comparison, few genes (422) showed significant change in the RV apex tissue. Apex-selective genes included two genes affecting metabolism and a stretch-sensitive transcription factor (ankyrin repeat domain 1). We conclude that the RV outflow tract is subject to strong proinflammatory and profibrotic remodeling transcriptional responses in chronic PE. Severe loss of genes involved in cellular respiration is consistent with previous histology indicating a shift in cell types present within the outflow tract tissue away from highly energy-dependant cardiomyocytes to less metabolically active cells during remodeling. The apex region of the RV had few compensating adaptations.

Right ventricular (RV) damage contributes to poor clinical outcome after pulmonary embolism (PE). Our studies show that neutrophils contribute to RV dysfunction in rat PE. Present studies examine effects of the nonsteroidal anti-inflammatory drug, ketorolac, upon RV inflammation and dysfunction. RV inflammatory gene expression significantly increased 6 and 18 hours after PE [cytokine-induced neutrophil chemoattractant-1 (CINC-1) 18-fold and 24-fold; cyclooxygenase-2 21-fold and 32-fold]. Eighteen hours after PE, there was significant upregulation of adhesion molecules (selectin E 18-fold; intercellular adhesion molecule 1 14-fold), influx of neutrophils (myeloperoxidase activity 21-fold), depressed RV function (RV peak systolic pressure = 24 +/- 3 vs. 40 +/- 1 mm Hg; maximum rate of pressure development = 444 +/- 79 vs. 1533 +/- 146; maximum rate of pressure decrease = -357 +/- 50 vs. -651 +/- 44), and release of cardiac troponin I (7.8 +/- 1.9 ng/mL) compared with vehicle. Ketorolac (10 mg/kg, intraperitoneally) significantly reduced expression of CINC-1, cyclooxygenase-2, selectin E, and intercellular adhesion molecule 1, lowered neutrophil influx, improved RV function (RV peak systolic pressure was 34 +/- 3 mm Hg; maximum rate of pressure development = 1288 +/- 146; maximum rate of pressure decrease = -611 +/- 92), and marginally reduced cardiac troponin I release (P < 0.07) compared with PE alone. Ketorolac reduced CINC-1 stimulated chemotaxis of isolated neutrophils. PE converted cardiac tissue into a proinflammatory phenotype. Ketorolac reduced RV inflammatory genes, reduced neutrophil influx, and improved RV function in rat PE.

Acute pulmonary embolism (PE) is the third leading cause of cardiovascular death in the United States. Moderate to severe PE can cause pulmonary arterial hypertension (PH) with resultant right ventricular (RV) heart damage. The mechanisms leading to RV failure after PE are not well defined, although it is becoming clear that PH-induced inflammatory responses are involved. We previously demonstrated profound neutrophil-mediated inflammation and RV dysfunction during PE that was associated with increased expression of several chemokine genes. However, a complete assessment of transcriptional changes in RVs during PE is still lacking. We have now used DNA microarrays to assess the alterations in gene expression in RV tissue during acute PE/PH in rats. Key results were confirmed with real-time RT-PCR. Nine CC-chemokine genes (CCL-2, -3, -4, -6, -7, -9, -17, -20, -27), five CXC-chemokine genes (CXCL-1, -2, -9, -10, -16), and the receptors CCR1 and CXCR4 were upregulated after 18 h of moderate PE, while one C-chemokine (XCL-1) and one CXC-chemokine (CXCL-12) were downregulated. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated increased expression of many inflammatory genes. There was also a major shift in the expression of components of metabolic pathways, including downregulation of fatty acid transporters and oxidative enzymes, a change in glucose transporters, and upregulation of stretch-sensing and hypoxia-inducible transcription factors. This pattern suggests an extensive shift in cardiac physiology favoring the expression of the "fetal gene program."