(Circulation. 2000;101:1436.)
© 2000 American Heart Association, Inc.
Basic Science Reports |
From the Center for Cardiopulmonary Pharmacology, University of Milan (Italy) (A.S., G.R., C.B., A.B., G.F.); the Department of Pharmacology, Chemotherapy, and Toxicology, University of Milan (Italy) (F.B.); and U-348, INSERM, Hopital Lariboisière, Paris, France (J.M.).
Correspondence to G. Folco, Center for Cardiopulmonary Pharmacology, University of Milan, Via Balzaretti 9, 0133 Milan, Italy. E-mail giancarlo.folco{at}unimi.it
| Abstract |
|---|
|
|
|---|
Methods and ResultsWe studied the effect of pretreatment with a monoclonal antibody directed against the CD18 subunit of PMNL ß2-integrin on the synthesis of cys-LT in a PMNL-perfused isolated rabbit heart in vitro and in a model of permanent ligature of the left descending coronary artery in the rabbit in vivo. Challenge of PMNL-perfused rabbit hearts with formyl-met-leu-phe (0.3 µmol/L) caused synthesis of cys-LT and increase in coronary perfusion pressure that were prevented by the anti-CD18 antibody. Similar results were obtained with the use of A-23187 (0.5 µmol/L) as a challenge. Persistence of PMNL-associated myeloperoxidase activity in the perfusion buffer was observed in the presence of the anti-CD18 antibody, indicating decreased PMNL infiltration. Coronary artery ligature in vivo increased urinary excretion of leukotriene E4, supporting the activation of the 5-lipoxygenase pathway during experimental acute myocardial infarction. Pretreatment with the anti-CD18 antibody (1 mg/kg) prevented the increase in leukotriene E4 excretion.
ConclusionsThese data support the importance of adhesion in promoting cys-LT formation, originating from PMNLendothelial cell cooperation, and contributing to myocardial stiffness and increased coronary resistance.
Key Words: leukocytes endothelium cell adhesion molecules prevention
| Introduction |
|---|
|
|
|---|
Leukotriene C4, D4, and E4 (cys-LT) are potent vasoactive mediators that constrict small and large vessels and modify cardiac and coronary functions, the microcirculation, and some of the manifestations of ischemia-reperfusion injury.4 5 Additionally, they have vasopermeant properties that might be of relevance for the extravasation of leukocytes from the vessel lumen to the tissue.6 Their generation exhibits remarkable cellular specificity; however, cys-LT formation also may occur through transfer of reactive intermediates between adjacent cells, which represents a specialized mode of cell-cell communication.7 PMNL-platelet interactions involving the lipoxygenase pathway, which may be important in hemostasis and inflammation, were first documented by Marcus et al.8 More recently, cooperation of donor PMNL with acceptor EC in processing the reactive intermediate LTA4 into biologically active LTC4 has been demonstrated.9 This process has been termed "transcellular biosynthesis" and suggests that the cellular environment (ie, cell-cell interactions) represents an important control mechanism in the production of eicosanoids, which may ultimately affect organ function.10 Indeed, challenge of PMNL within the coronary vasculature causes coronary vasoconstriction11 associated with PMNL extravasation and widespread perivascular edema,12 both dependent on endogenous cys-LT formation. PMNL-EC adhesion is regulated by several cell-surface adhesion molecules; among them PMNL ß2-integrins are known to play a significant role in firm adhesion of PMNL to EC.2
In the present study, we provide evidence that a monoclonal antibody (mAb) directed against the CD18 subunit of PMNL ß2-integrins (a) inhibits cys-LT generation decreasing PMNL-dependent tissue edema and coronary resistance in the isolated heart of the rabbit in vitro and (b) inhibits the increased urinary leukotriene excretion occurring after acute myocardial infarction of the left ventricular wall in the rabbit in vivo.
| Results |
|---|
|
|
|---|
High-performance liquid chromatography (HPLC)
analysis of the total volume of the circulating
perfusate (44 to 47 mL) collected at the end of the experiment
allowed positive identification of cys-LT by on-line UV-spectrum
analysis. Pretreatment with the anti-CD18 antibody (6.5E, 5
µg/mL) resulted in a significant inhibition of the increase in
coronary perfusion pressure (CPP), allowing survival of all
isolated hearts throughout the observation period of 60 minutes, and
was accompanied by a significant decrease in cys-LT formation (Figure 1
). LVEDP values did not differ from
basal values (5±0.2 mm Hg, n=4). The assay of cell-associated
myeloperoxidase (MPO) enzyme activity in the recirculating buffer
confirmed a rapid disappearance of MPO in the presence of control mAb,
whereas pretreatment with the anti-CD18 mAb resulted in a significantly
inhibited adhesion of PMNL (Figure 2
).
|
|
To test whether the observed effect of the anti-CD18 antibody could be
reversed by a more sustained activation of the
5-lipoxygenase (5-LO), PMNL-perfused, isolated
hearts were challenged with A-23187 (0.5 µmol/L). As previously
reported,11 challenge with A-23187 induced the
PMNL-dependent formation of cys-LT, together with a significant
increase in CPP, which resulted in arrest in systole in 3 of 4 isolated
hearts within 20 to 30 minutes after challenge. As observed with fMLP,
pretreatment with the anti-CD18 mAb significantly reduced the increase
in CPP, and all isolated hearts survived throughout the observation
period of 30 minutes (Figure 3
, left) and
resulted in a marked suppression of the formation of cys-LT (Figure 3
, right), suggesting the pivotal role of adhesion in their
production.
|
The assay of circulating PMNL provided evidence of efficacy of the
pretreatment with the anti-CD18 antibody in inhibiting PMNL adhesion.
After A-23187 activation, a rapid disappearance of PMNL from the
recirculating buffer was observed, suggesting intravascular adhesion.
However, pretreatment with the anti-CD18 mAb resulted in persistence of
PMNL-associated MPO activity in the recirculating buffer as a result of
inhibited adhesion (Figure 4
).
|
Challenge with fMLP (0.3 µmol/L, 60 minutes) of GM-CSFprimed PMNL preparations in suspension showed a substantial release of LTA4 metabolites, which was not affected by pretreatment with anti-CD18 mAb 6.5E (25.5±3.4 vs 31.1±2.9 pmol/106 PMNL in control and anti-CD18treated cells, respectively; n=3). Similarly, production of LTA4 metabolites on challenge with A-23187 (0.5 µmol/L, 30 minutes) was not affected by pretreatment with the anti-CD18 mAb (5 µg/mL-1) (291.3±13.7 vs 265.3±10.3 pmol/106 PMNL in control and anti-CD18treated cells, respectively; n=3).
In Vivo Studies
Excretion of LTE4 in urine was evaluated
during the 3 hours after permanent ligature of the left descending
coronary artery (coronary artery ligature, CAL) in the
rabbit, resulting in acute myocardial infarction of the left
ventricular wall, and was compared with the values obtained
in sham-operated animals. Urinary excretion of
LTE4 was significantly higher in the CAL group,
treated with the nonbinding IgG1 mAb MOPC-21 (1 mg/kg IV, 15 minutes
before ligature), indicating endogenous production
of cys-LT during the ischemia associated with the
coronary ligature. Treatment with the anti-CD18 mAb 6.5E (1
mg/kg IV, 15 minutes before ligature) fully prevented the increase in
LTE4 excretion (Figure 5
).
|
| Discussion |
|---|
|
|
|---|
Neither PMNL nor EC can synthesize cys-LT from the precursor AA; however, the former have been shown to produce predominantly LTA4,13 whereas the latter possess a remarkably effective metabolic capacity for cys-LT from the epoxide precursor LTA4. It is therefore likely that during adhesion, a privileged interface between the donor PMNL and the acceptor EC is formed, creating the necessary conditions to transfer the unstable intermediate LTA4. LTC4-activated endothelium may then become adhesive for PMNL through the surface expression of platelet-activating factor14 and P-selectin, providing a self-amplifying loop that may result in increased transcellular synthesis of cys-LT.
The mechanism that explains the increase in coronary vascular resistance and myocardial stiffness involves activated PMNL attaching to the vascular endothelium and triggering transcellular biosynthesis of cys-LT; local formation of cys-LT results in edema formation and extravascular compression of coronary microvessels, as previously shown by scanning electron microscopy.12 Local production of cys-LT also may contribute to active coronary vasoconstriction; in fact, the increase in coronary perfusion pressure evoked by PMNL activation is partially reversible after intracoronary injection of sodium nitroprusside.11 The inhibition of PMNL-EC adhesion by the anti-CD18 mAb, reducing cell-cell contact and making transcellular biosynthesis events much less efficient, exerts protective effects against cardiac inflammation and its functional outcomes.
We used the presence of cell-associated MPO activity as an indirect tool to quantitatively evaluate the extent of PMNL adhesion to its target cells and obtained evidence that anti-CD18 mAb effectively blunted PMNL sequestration through the coronary bed. A significant body of evidence supports the notion that the inflammatory tissue damage that accompanies ischemia or ischemia-reperfusion is mediated to a large extent by PMNL.15 Accordingly, prevention of leukocyte-EC interaction, through the use of mAbs directed against adhesion molecules, has proven successful in limiting ischemic damage in experimental models.16 17 A study with isolated PMNLglomerular EC coincubations showed that transcellular synthesis of cys-LT was inhibited by pretreatment with an anti-CD18 mAb.18 Our work extends these findings to a functional organ system and provides a link between adhesion of PMNL, synthesis of cys-LT, and functional modifications.
The model of in vitro PMNL-dependent cardiac damage used for this study is different from more complex in vivo models of ischemia-reperfusion injury. Recently, a 54% reduction in PMNL accumulation and a 57% decrease of myocardial necrosis after ischemia-reperfusion was observed in CD18-deficient mice and intracellular adhesion molecule-1deficient mice,19 supporting a critical role of these cell adhesion molecules in myocardial cell injury of the reperfused myocardium. The more significant functional protection observed in our study (>80% inhibition of increase in CPP and LVEDP) is not unexpected given the fact that our model is uniquely PMNL dependent, whereas it is conceivable that in vivo other cells and factors may contribute to the development of the cardiac injury.
Measurement of LTE4 in urine has been largely adopted as a noninvasive, time-integrated index of cysteinyl leukotriene synthesis in vivo. Evaluation of urinary LTE4 excretion showed a significant increase after permanent coronary ligature in the rabbit, in agreement with the results of 2 independent groups reporting increased urinary LTE4 excretion in patients with coronary artery disease and in patients after myocardial infarction.20 21 The observed inhibition after pretreatment with anti-CD18 antibody supports the hypothesis that pathophysiologically relevant cys-LT formation within an ischemic myocardium may represent the outcome of transcellular biosynthetic events.
The increased urinary excretion of LTE4 associated with the CAL observed in the present study is also clearly complementary with our previous results with the same model, in which we showed a significant decrease of the mortality rate by pretreatment with a specific leukotriene synthesis 5-lipoxygenase-activating protein (FLAP) inhibitor.22
Although it may seem difficult to hypothesize the infiltration of neutrophils into the infarcted area in the time course described, we must point out that under our working hypothesis there is no need to have actual neutrophil infiltration, but it would be sufficient for them to adhere to EC to achieve local leukotriene formation associated with altered vascular permeability and tone. In fact, it has recently been shown that increased endothelial permeability occurs even in the absence of neutrophil infiltration.23
The leukocyte count has been originally proposed as a valuable routine index for the assessment of risk for myocardial infarction.24 Since then, a number of epidemiological studies have shown the existence of a significant relation between blood white cell count and the occurrence of coronary heart disease (eg, angina pectoris and myocardial infarction).25 Furthermore, enhanced neutrophil expression of CD11b/CD18 adhesion receptors has been recently reported in patients with unstable angina.26 Our data, supporting the functional relevance of CD18-mediated, PMNL-dependent synthesis of cys-LT, provide a link between PMNL implication in the natural history of coronary heart disease and increased urinary LTE4 levels in patients with cardiac ischemia, two observations apparently uncorrelated.
In conclusion, we propose that among the PMNL-dependent factors contributing to the development of cardiac damage associated with ischemia, the production of cys-LT through transcellular biochemical mechanisms may have a significant role and may represent a potential therapeutic target.
| Methods |
|---|
|
|
|---|
PMNL (2x107 mL-1) were primed with granulocyte macrophage-colony stimulating factor (GM-CSF, 1 nmol/L, 30 minutes) (Amersham International), supplied with Ca2+ (2 mmol/L) and Mg2+ (0.5 mmol/L), and allowed to equilibrate for 5 minutes at 37°C before perfusion and challenge.
Isolated Perfused Heart Preparation
Albino rabbits (weight 2.5 to 3.0 kg, BMG-Allevamento, Cividate
al Piano, BG, Italy) were used. Hearts were isolated and perfused
retrogradely at 37°C through the aorta as previously
described.27 CPP and LVEDP were monitored
continuously.
Cell-Perfused Hearts
PMNL (5x106 to 107
cells) were diluted to 3 mL in Tyrodes solution and slowly infused
into the recirculating medium of isolated rabbit hearts.
Challenge with 0.3 µmol/L fMLP (Sigma Chemical Co) was performed 10 minutes after addition to the recirculating reservoir; alternatively, challenge with 0.5 µmol/L A-23187 was performed with the use of unprimed PMNL. Isolated hearts were observed up to 60 minutes after fMLP challenge and up to 30 minutes after activation with A-23187.
Analysis of Leukotrienes in Heart
Perfusates by HPLC
The entire heart reservoir (
45 mL) was collected, spiked with
50 000 dpm 3H-LTD4 and 25
ng of PGB2, and stored at -20°C until
analysis.22 Briefly, samples were extracted on
solid-phase cartridges (Mega Bond-Elut C8, Varian) and eluted with 4 mL
of ethyl acetate/methanol (99:1) and 4 mL of methanol/water (90:10).
The ethyl acetate fractions containing PGB2 and
the hydroxy-arachidonic acid derivative
LTB4 were injected into an HPLC gradient pump
system (Beckman model 126) connected to a diode-array UV detector
(Beckman model 168). A multilinear gradient from solvent A
(methanol/acetonitrile/water/acetic acid,
10:10:80:0.02,vol/vol/vol/vol, pH 5.5, with ammonium hydroxide)
to solvent B (50% methanol, 50% acetonitrile) was used. The dried
methanolic extracts, containing cysteinyl leukotrienes
only, were reconstituted in HPLC solvent A (0.6 mL) containing 25 ng of
PGB2; radioactivity was measured with the use of
a ß-counter (Packard model 4000) to assess recovery of cysteinyl
leukotrienes (40% to 70%). The remaining sample was
injected into the same HPLC system used for
LTB4.
Positive identification of leukotrienes was obtained through UV spectral analysis and quantitation was performed on positively identified peaks only. Intra-assay variability was <7% for cys-LT and LTB4, and values of cys-LT were corrected for the recovery of radioactive tracer.
Isolated Cell Incubation
PMNL (107 mL-1)
were challenged with fMLP (0.3 µmol/L) or A-23187 (0.5
µmol/L), and stimulation was terminated after 60 and 30 minutes,
respectively. Incubates were extracted with the use of solid-phase
cartridges (Oasis, 1 mL, Waters), eluted with 90% aqueous methanol,
taken to dryness, reconstituted, and analyzed as previously
described.13
Quantitative Analysis of Circulating PMNL
MPO activity associated with circulating PMNL was used as a
marker for indirect evaluation of PMNL adhesion. Aliquots (1 mL) of the
buffer recirculating through the isolated hearts were withdrawn at
different time intervals and centrifuged at 12 000g
(2 minutes). The supernatant was carefully removed and cell pellets
were resuspended in 200 µL phosphate buffer, 50 mmol/L, pH 6.0,
containing 0.5% (wt/vol), hexamethyltetraammonium bromide and 0.1%
(wt/vol) gelatin. Samples (kept on ice) were then sonicated and
centrifuged at 13 000g (15 minutes).
MPO activity was assayed in the supernatant by measuring the H2O2-dependent oxidation of TMB.28 Samples were incubated for 5 minutes at 37°C and the reaction blocked by the addition of bovine catalase. Oxidized TMB develops a blue color, which was measured spectrophotometrically at 620 nm.
In Vivo Experiments
Animal Preparation
Male Albino rabbits (weight 2.4 to 2.6 kg) were
anesthetized with 30 mg/kg IV sodium pentothal. After
laparotomy, the bladder was manually voided and, under artificial
respiration, the left side of the thorax was opened through the fourth
to fifth intercostal space. The small branch of the left anterior
descending coronary artery was separated from the myocardial
tissue and ligated with a silk 6.0 suture. Pericardiotomy and isolation
of the coronary artery without ligature was performed in
sham-operated animals (n=6). Rabbits with permanent CAL, were
pretreated (15 minutes) either with 1 mg/kg of an anti-CD18 mAb (6.5E,
n=4) or 1 mg/kg of a homotypic, nonbinding mAb as control (MOPC-21,
n=6). The bladder was again fully voided at 3 hours after ligature and
urine immediately stored at -80°C for LTE4
analysis.
Measurement of Urinary LTE4
Urinary LTE4 was evaluated according to
Westcott et al29 with minor modifications. Briefly, urine
(10 to 20 mL) was thawed, centrifuged, and 0.4 mL was added
with 50 µg of an anticys-LT mAb (Biomol). After 4 hours of
incubation at room temperature, LTE4-antibody
complexes were extracted by filtration over Centricon 10 000
microfilters (Amicon), and LTE4 was freed with
methanol (500 µL). After centrifugation
(12 000g, 10 minutes) the supernatant was taken to dryness,
reconstituted in 300 µL of appropriate buffer, and
LTE4 was quantified with the use of a commercial
enzyme immunoassay (Cayman Chem).
Statistical Analysis
All values in the text and figures are expressed as mean±SEM of
the number of observations. A 2-way ANOVA was used to analyze
results from repeated measurements. Results of urinary
LTE4 excretion were analyzed by 1-way
ANOVA followed by Dunnetts test versus the sham-operated group.
Probability values <0.05 were considered statistically
significant.
| Acknowledgments |
|---|
| Footnotes |
|---|
The Methods section of this article can be found at http://www.circulationaha.org
Received July 7, 1999; revision received October 1, 1999; accepted October 6, 1999.
| References |
|---|
|
|
|---|
2.
Carlos TM, Harlan JM.
Leukocyte-endothelial adhesion molecules.
Blood. 1994;84:20682101.
3. Lewis RA, Austen KF, Soberman RJ. Leukotrienes and other products of the 5-lipoxygenase pathway: biochemistry and relation to pathobiology in human diseases. N Engl J Med. 1990;323:645655.[Medline] [Order article via Infotrieve]
4. Feuerstein G. Cardiac and vascular effects of leukotrienes. Adv Prostaglandin Thromboxane Leukot Res. 1986;16:299308.[Medline] [Order article via Infotrieve]
5.
Michelassi F, Landa L, Hill RD, Lowenstein E, Watkins
WD, Petkau AJ, Zapol WM. Leukotriene
D4: a potent coronary artery
vasoconstrictor associated with impaired ventricular
contraction. Science. 1982;217:841843.
6.
Dahlen SE, Bjork J, Hedqvist P, Arfors KE, Hammarstrom
S, Lindgren JA, Samuelsson B. Leukotrienes promote plasma
leakage and leukocyte adhesion in postcapillary venules: in vivo
effects with relevance to the acute inflammatory response. Proc
Natl Acad Sci U S A. 1981;78:38873891.
7.
Maclouf J, Murphy RC, Henson PM. Transcellular
sulfidopeptide leukotriene biosynthetic capacity of
vascular cells. Blood. 1989;74:703707.
8. Marcus AJ, Broekman MJ, Safier LB, Ullman HL, Islam N, Sherhan CN, Rutherford LE, Korchak HM, Weissmann G. Formation of leukotrienes and other hydroxy acids during platelet-neutrophil interactions in vitro. Biochem Biophys Res Commun. 1982;109:130137.[Medline] [Order article via Infotrieve]
9. Feinmark SJ. The role of the endothelial cell in leukotriene biosynthesis. Am Rev Respir Dis. 1992;146:S51S55.[Medline] [Order article via Infotrieve]
10. Sala A, Maclouf J. Transcellular biosynthesis of leukotrienes: a unique mode of cell communication. In: Folco G, Murphy R, Samuelsson B, eds. Inhibitors of Leukotrienes. Basel, Switzerland: Birkhauser; 1999:113124.
11. Sala A, Rossoni G, Buccellati C, Berti F, Folco G, Maclouf J. Formation of sulphidopeptide-leukotrienes by cell-cell interaction causes coronary vasoconstriction in isolated, cell-perfused heart of rabbit. Br J Pharmacol. 1993;110:12061212.[Medline] [Order article via Infotrieve]
12.
Sala A, Aliev GM, Rossoni G, Berti F, Buccellati C,
Burnstock G, Folco G, Maclouf J. Morphological and functional changes
of coronary vasculature caused by transcellular biosynthesis of
sulfidopeptide leukotrienes in isolated heart of rabbit.
Blood. 1996;87:18241832.
13.
Sala A, Bolla M, Zarini S, Muller-Peddinghaus R, Folco
G. Release of leukotriene A4 versus
leukotriene B4 from human
polymorphonuclear leukocytes. J Biol Chem. 1996;271:1794417948.
14.
McIntyre TM, Zimmerman GA, Prescott SM.
Leukotrienes C4 and
D4 stimulate human endothelial
cells to synthesize platelet-activating factor and bind
neutrophils. Proc Natl Acad Sci U S A. 1986;83:22042208.
15. Lucchesi BR, Werns SW, Fantone JC. The role of the neutrophil and free radicals in ischemic myocardial injury. J Mol Cell Cardiol. 1989;21:12411251.[Medline] [Order article via Infotrieve]
16. Jolly SR, Kane WJ, Hook BG, Abrams GD, Kunkel SL, Lucchesi BR. Reduction of myocardial infarct size by neutrophil depletion: effect of duration of occlusion. Am Heart J. 1986;112:682690.[Medline] [Order article via Infotrieve]
17.
Ma XL, Weyrich AS, Lefer DJ, Buerke M, Albertine KH,
Kishimoto TK, Lefer AM. Monoclonal antibody to L-selectin attenuates
neutrophil accumulation and protects ischemic reperfused cat
myocardium. Circulation. 1993;88:649658.
18. Brady HR, Serhan CN. Adhesion promotes transcellular leukotriene biosynthesis during neutrophil-glomerular endothelial cell interactions: inhibition by antibodies against CD18 and L-selection. Biochem Biophys Res Commun. 1992;186:13071314.[Medline] [Order article via Infotrieve]
19. Palazzo AJ, Jones SP, Girod WG, Anderson DC, Granger DN, Lefer DJ. Myocardial ischemia-reperfusion injury in CD18- and ICAM-1-deficient mice. Am J Physiol. 1998;275:H2300H2307.
20.
Carry M, Korley V, Willerson JT, Weigelt L,
Ford-Hutchinson AW, Tagari P. Increased urinary leukotriene
excretion in patients with cardiac ischemia: in vivo evidence
for 5-lipoxygenase activation. Circulation. 1992;85:230236.
21. Allen SP, Sampson AP, Piper PJ, Chester AH, Ohri SK, Yacoub MH. Enhanced excretion of urinary leukotriene E4 in coronary artery disease and after coronary artery bypass surgery. Coron Artery Dis. 1993;4:899904.[Medline] [Order article via Infotrieve]
22.
Rossoni G, Sala A, Berti F, Testa T, Buccellati C,
Molta C, Muller-Peddinghaus R, Maclouf J, Folco GC. Myocardial
protection by the leukotriene synthesis
inhibitor BAY X1005: importance of transcellular
biosynthesis of cysteinyl-leukotrienes. J
Pharmacol Exp Ther. 1996;276:335341.
23. Gautam N, Hedqvist P, Lindbom L. Kinetics of leukocyte-induced changes in endothelial barrier function. Br J Pharmacol. 1998;125:11091114.[Medline] [Order article via Infotrieve]
24. Friedman GD, Klatsky AL, Siegelaub AB. The leukocyte count as a predictor of myocardial infarction. N Engl J Med. 1975;290:12751278.
25. Lowe GDO, Machado SG, Krol WF, Barton BA, Forbes CD. White blood cell count and haematocrit as predictors of coronary recurrence after myocardial infarction. Thromb Haemost. 1985;54:700703.[Medline] [Order article via Infotrieve]
26.
Mazzone A, DeServi S, Ricevuti G, Mazzucchelli I,
Fossati G, Pasotti D, Bramucci E, Angoli L, Marsico F, Specchia G,
Notario A. Increased expression of neutrophil and monocyte adhesion
molecules in unstable coronary artery disease.
Circulation. 1993;88:358363.
27. Berti F, Rossoni G, Magni F, Caruso D, Omini C, Puglisi L, Galli G. Non steroidal antiinflammatory drugs aggravate acute myocardial ischemia in perfused rabbit heart: a role for prostacyclin. J Cardiovasc Pharmacol. 1988;12:438444.[Medline] [Order article via Infotrieve]
28. Schierwagen C, Bylund-Fellenius AC, Lundberg C. Improved method for quantification of tissue PMN accumulation measured by myeloperoxidase activity. J Pharmacol Methods. 1990;23:179186.[Medline] [Order article via Infotrieve]
29. Westcott JY, Sloan S, Wenzel SE. Immunofiltration purification for urinary leukotriene E4 quantitation. Anal Biochem. 1997;248:202210.[Medline] [Order article via Infotrieve]
This article has been cited by other articles:
![]() |
G. Folco and R. C. Murphy Eicosanoid Transcellular Biosynthesis: From Cell-Cell Interactions to in Vivo Tissue Responses Pharmacol. Rev., September 1, 2006; 58(3): 375 - 388. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Dickinson Zimmer, D. F. Dyckes, D. A. Bernlohr, and R. C. Murphy Fatty acid binding proteins stabilize leukotriene A4: competition with arachidonic acid but not other lipoxygenase products J. Lipid Res., November 1, 2004; 45(11): 2138 - 2144. [Abstract] [Full Text] [PDF] |
||||
![]() |
W Anne, R Willems, N Van der Merwe, F Van de Werf, H Ector, and H Heidbuchel Atrial fibrillation after radiofrequency ablation of atrial flutter: preventive effect of angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, and diuretics Heart, September 1, 2004; 90(9): 1025 - 1030. [Abstract] [Full Text] [PDF] |
||||
![]() |
J Martel-Pelletier, D Lajeunesse, P Reboul, and J-P Pelletier Therapeutic role of dual inhibitors of 5-LOX and COX, selective and non-selective non-steroidal anti-inflammatory drugs Ann Rheum Dis, June 1, 2003; 62(6): 501 - 509. [Abstract] [Full Text] [PDF] |
||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2000 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |