ATS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Patrick E. Parrino
Robert C. King
Curtis G. Tribble
Irving L. Kron
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Parrino, P. E.
Right arrow Articles by Kron, I. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Parrino, P. E.
Right arrow Articles by Kron, I. L.

Ann Thorac Surg 1998;66:733-739
© 1998 The Society of Thoracic Surgeons

Original articles: Cardiovascular

Inhibition of inducible nitric oxide synthase after myocardial ischemia increases coronary flow

Patrick E. Parrino, MDa, Victor E. Laubach, PhDa, John R. Gaughen, Jr, BAa, Kimberly S. Shockey, MSa, Terri-Ann Wattsman, MDa, Robert C. King, MDa, Curtis G. Tribble, MDa, Irving L. Kron, MDa

a Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Virginia Health Sciences Center, Charlottesville, Virginia, USA

Address reprint requests to Dr Kron, Department of Surgery, Box 310, University of Virginia Health Sciences Center, Charlottesville, VA 22908
e-mail: (ikron{at}virginia.edu)

Presented at the Forty-fourth Annual Meeting of the Southern Thoracic Surgical Association, Naples, FL, Nov 6–8, 1997.


   Abstract
Top
 Abstract
Introduction
 Material and methods
 Results
 Comment
 Acknowledgments
 References
 
Background. The role of nitric oxide synthase in myocardial ischemia–reperfusion injury is complex. Our hypothesis was that inducible nitric oxide synthase has a role in the regulation of coronary flow after ischemia.

Methods. Four groups of isolated blood-perfused rabbit hearts underwent sequential periods of perfusion, ischemia, and reperfusion (20, 30, and 20 minutes). Two groups underwent 40 minutes of perfusion. Ischemic groups received saline vehicle, N{omega}-nitro-L-arginine methyl ester (L-NAME) or the highly specific inducible nitric oxide synthase inhibitor 1400W in low or high doses during reperfusion. Two nonischemic groups were treated with saline vehicle or 1400W during the last 20 minutes of perfusion. Left ventricular developed pressure and coronary flow were measured after each perfusion period. Ventricular levels of myeloperoxidase and cyclic guanosine monophosphate were measured at the end of the second perfusion period.

Results. Coronary flow was significantly increased in both 1400W groups versus L-NAME (p < 0.001) and in high-dose 1400W versus control (p < 0.001). Coronary flow was not significantly different between the nonischemic groups. Left ventricular developed pressure was not significantly different among the ischemic groups or between the two nonischemic groups. There were no differences in cyclic guanosine monophosphate levels in any of the ischemic hearts. Myeloperoxidase levels were significantly elevated in L-NAME versus high-dose 1400W, nonischemic 1400W, and nonischemic saline groups (p < 0.02).

Conclusions. Highly selective inhibition of inducible nitric oxide synthase results in increased coronary flow after ischemia but not after continuous perfusion. This occurs with decreased neutrophil accumulation and a trend toward increased contractility without elevation of cyclic guanosine monophosphate levels.


   Introduction
Top
 Abstract
 Introduction
Material and methods
 Results
 Comment
 Acknowledgments
 References
 
The role of nitric oxide synthase (NOS) and its product, nitric oxide (NO), in myocardial ischemia–reperfusion injury is complex and has not been clearly defined. Many studies that demonstrate a beneficial role for NO after ischemia–reperfusion use either the substrate for NOS (L-arginine), a NOS inhibitor, or both [1–5]. Other studies use the same substrate or inhibitor and report a contrary response [6–9]. Data from different studies that often seems contradictory may be explained, in part, by a bimodal effect of NO that is the result of the timing of administration of either inhibitors or substrate. Defining a clear role for NOS has been further complicated by the elucidation of three different isoforms of NOS: endothelial NOS (eNOS), inducible NOS (iNOS), and neuronal NOS. In the heart, NO is produced under basal conditions predominantly by eNOS. After appropriate stimulus (lipopolysaccharide, interleukin-1ß, tumor necrosis factor-{alpha}, interferon-{gamma}, interleukin-6, and ischemia) cardiac myocytes, microvascular endothelium, endocardial endothelial cells, and vascular smooth muscle cells, as well as certain inflammatory cells (macrophages, neutrophils), may also express iNOS in a time-dependent fashion [10, 11]. Neuronal NOS is thought to play a relatively minor role in the generation of NO in the heart [10].

An additional factor that has made the role of NOS after ischemia–reperfusion difficult to sort out is the lack of specific inhibitors for the various isoforms. Commonly used inhibitors of NOS such as L-NAME (N{omega}-nitro-L-arginine methyl ester) and L-NMMA (NG-monomethyl-L-arginine) are L-arginine analogs that compete for binding with L-arginine and lack specificity for any of the known NOS variants.

We developed the hypothesis that both eNOS and iNOS have a role in the regulation of coronary flow after ischemia, and that selective inhibition of iNOS might improve postischemic myocardial function without compromising the ability of the endothelium to synthesize appropriate amounts of NO.


   Material and methods
Top
 Abstract
 Introduction
 Material and methods
Results
 Comment
 Acknowledgments
 References
 
All protocols in this study were reviewed and approved by the Animal Review Committee of the University of Virginia. All animals received humane care in compliance with the "Principles of Laboratory Animal Care" as described by the National Society for Medical Research and the "Guide for the Care and Use of Laboratory Animals" (NIH publication 85-23, revised 1985). Adult New Zealand white rabbits of either sex were used throughout this study.

Preparation of donor animal and organ harvest
New Zealand white rabbits (2.8 to 3.0 kg) were anesthetized with an intramuscular injection of xylazine (10 mg) and ketamine (100 mg); this was followed by placement of an ear vein catheter and a tracheostomy, and volume ventilation (12 mL/kg) with 100% oxygen was begun. Vecuronium bromide (0.2 mg) and 2,000 units of heparin sodium were administered intravenously. A sternotomy was performed and the aorta isolated. The inferior vena cava was then transected, followed by a rapid aortotomy and insertion of a saline-filled stainless steel cannula, which was secured in place. The hearts were then quickly excised and immediately reperfused ex vivo in the Langendorff mode.

Establishment of perfusion and baseline data
All hearts were reperfused with oxygenated whole blood from a support animal as described in detail by Mauney and coworkers [12] (Fig 1). In brief, a support rabbit was used to provide oxygenated blood through a perfusion circuit to the isolated heart. This blood was filtered and warmed (37°C) before passing an ultrasonic flow probe (Transonic Systems, Inc, Ithaca, NY) and entering the cannula. The perfusion pressure was a constant 80 mm Hg, which is the normal physiologic perfusion pressure of the rabbit heart. Transfusion of blood from a blood-donor rabbit was used as needed to maintain adequate circulating blood volume in the support animal. All hearts were allowed to equilibrate during the first 10 minutes of perfusion. At 10 minutes, pacing leads were attached to the right ventricular free wall and the hearts were paced at 150 Hz. Subsequently, a left atriotomy was made and the mitral valve was gently disrupted. A saline-filled latex balloon was then placed into the left ventricle for continuous measurement of left ventricular developed pressure. Baseline data were collected for an additional 10 minutes.



View larger version (27K):
[in this window]
[in a new window]
  		Fig 1. Schematic of the isolated, blood-perfused heart circuit. (Vent = ventilator.)

 
Experimental design
Six groups of rabbits were studied. All groups underwent harvest, equilibration, and baseline data collection as described above. Four groups were subjected to a 30-minute period of warm ischemia by occlusion of the aortic cannula and immersion in a warm saline bath (37°C). Hearts were not paced during this time. After this interval, the saline bath was drained, perfusion was restarted, and the hearts were again paced at 150 Hz. Simultaneously, infusion of drug or saline vehicle was begun. An infusion pump (syringe infusion pump 22; Harvard Apparatus, South Natick, MA) was connected to a side port in the aortic cannula and was used to administer drug directly into the coronary circulation. The infusate was given at a constant rate of 0.25 mL/min. The hearts were reperfused for 20 minutes before removal from the apparatus. During reperfusion, effluent blood from the isolated heart was discarded and not returned to the support animal, thus limiting drug exposure to the isolated heart only. After removal from the apparatus, the hearts were gently flushed with 20 mL of normal saline solution through the cannula, the right ventricular free wall and atria were dissected away, and the left ventricle was immersed in liquid nitrogen. The frozen hearts were then stored at -80°C for later assay. Two groups of animals did not undergo warm ischemia; rather, after 20 minutes of equilibration, infusion of drug or vehicle was begun at the aforementioned rate. As in the other four groups, 20 minutes of data were collected before removal, flushing, trimming, and freezing. The infusates in the four ischemic groups consisted of saline vehicle, L-NAME (1 µg/min, Sigma Chemical Co, St. Louis, MO), low-dose 1400W (N-[3-(aminomethyl)benzyl] acetamidine, 5 µg/min, provided by Glaxo-Wellcome Research, Hertfordshire, UK), and high-dose 1400W (50 µg/min). Drugs were prepared in appropriate concentrations to allow a uniform infusion rate in all groups. The dose of L-NAME was selected based on a previous study in which a rabbit model was used to study the effect of L-NAME on regional myocardial ischemia–reperfusion [13]. The dose of 1400W was chosen based on previous work that examined the efficacy of 1400W in preventing vascular leakage caused by endotoxin [14]. In that study, the authors found a median effective dose ED50 of 0.3 mg/kg in their study animals. In the present study, the mass of the typical rabbit heart was approximately 10 g, resulting in a dose of 0.005 mg/heart. However, because the blood was not recirculated, this dose was used on a per minute basis to approximate the in vivo exposure of the heart to 1400W. The two nonischemic groups received saline vehicle or low-dose 1400W. Groups were defined according to the specific interventions that were made (Table 1).


View this table:
[in this window]
[in a new window]
  		Table 1. Experimental Groups

 
Data acquisition during reperfusion of isolated hearts
Throughout the 20-minute reperfusion period, data were obtained from the in-line ultrasonic flow probe and the left ventricular balloon. These continuous data were collected and recorded by customized digital data acquisition software (Workbench PC; Strawberry Tree, Inc, Sunnyvale, CA) and allowed analysis of coronary flow (CF), left ventricular developed pressure, and the first derivative of the left ventricular pressure.

Biochemical assays
The test hearts, which had been reduced to the left ventricle and quickly frozen in liquid nitrogen at the end of reperfusion, were stored at -80°C for later assay. Before assay, the hearts were removed from the freezer, crushed using a mortar and pestle on a bed of dry ice, and separated into 0.45- to 0.55-g samples. These samples were used to measure myeloperoxidase (MPO) activity and cyclic guanosine 3', 5' monophosphate (cGMP) levels.

Myeloperoxidase assay
To elucidate the role of neutrophils in ischemia–reperfusion injury, MPO was studied as a marker of neutrophil accumulation. Samples from all hearts were used to determine MPO activity. The samples were allowed to thaw and then were homogenized (Polytron model PCV 11, Kinnematica AG, Littau, Switzerland) in 2.5 mL of 0.05 mol/L Na2PO4 at 4°C for 30 seconds. The samples were then centrifuged (Sorvall RC-5B refrigerated superspeed centrifuge, DuPont Instruments, Newtown, CT) at 4°C, the supernatant was discarded, and the pellet was resuspended in 2.5 mL of 0.5% HTAB (hexadecyltrimethylammonium bromide). This solution was homogenized (Polytron model PCV 11) and sonicated (Bransonic ultrasonic cleaner 3210, Branson Ultrasonics Co, Danbury, CT) for 2 minutes at room temperature. The sample was then centrifuged (Sorvall RC-5B) at 4°C for 10 minutes and the supernatant removed. One tenth of a milliliter of the supernatant was then added to a stock solution of H2O2 and ODD (o-dianisidine dihydrochloride, Sigma) and placed immediately into the spectrophotometer (LKB Biochrom model 4050, Cambridge, England), and the change in absorbance at 460 nm measured over 2 minutes. Myeloperoxidase activity is reported as change in absorbance per gram tissue (wet weight) per minute.

Determination of myocardial cGMP content
Nitric oxide is known to activate the enzyme guanylyl cyclase, which then catalyzes the production of cGMP [15]. As a second messenger for NO, cGMP exerts effects directly on cGMP-sensitive ion channels and on cGMP-regulated cyclic adenosine 3', 5' monophosphate (cAMP) phosphodiesterases [16]. To evaluate tissue levels of cGMP, samples from hearts in all six groups were homogenized (Polytron model PCV 11) at 4°C in 5 mL of 6% trichloroacetic acid (J.T. Baker, Phillipsburg, NJ). They were then centrifuged (Sorvall RC-5B) for 15 minutes at 4°C. The supernatant was then removed and washed four times with ethyl ether (Fisher Scientific, Fair Lawn, NJ). The samples were then vacuum-dried at 60°C for 3 to 4 hours. The resulting pellet was then resuspended in 1 mL of 0.1 N HCl, and the solution was subjected to radioimmunoassay [17]. The results of all assays are reported as picomoles per gram of tissue (wet weight).

Statistical analysis
All results are expressed as the mean ± standard error of the mean. All functional, metabolic, and molecular data were analyzed for between-group differences using analysis of variance (ANOVA) and Tukey’s HSD test. Significance was defined as a p value less than 0.05. All analyses were performed using SPSS software (SPSS Inc, Chicago, IL).


   Results
Top
 Abstract
 Introduction
 Material and methods
 Results
Comment
 Acknowledgments
 References
 
Functional and metabolic data
Table 2 provides the mean CF data of isolated hearts after 20 minutes of baseline preintervention perfusion and after 20 minutes of postintervention (ischemia + drug or drug alone) perfusion. Also included in Table 2 is the percent of end-baseline CF present at end-reperfusion (% CF recovery). This value was calculated as follows: . The mean baseline CF before intervention was similar in all six groups; however, after ischemia followed by reperfusion with drug the CF was significantly reduced in the L-NAME group versus high-dose (HD) 1400W and low-dose (LD) 1400W groups. There was also a significant decrease in CF between the control group and HD 1400W. There was no significant difference between the two drug-only, nonischemic groups. Figure 2 represents the entire 20-minute postintervention perfusion period.


View this table:
[in this window]
[in a new window]
  		Table 2. Coronary Flow Before Intervention (Ischemia + Drug or Drug Alone), After 20 Minutes of Postintervention Perfusion, and Percent Recoverya

 


View larger version (31K):
[in this window]
[in a new window]
  		Fig 2. Coronary flow during postintervention perfusion. (L-NAME = N{omega}-nitro-L-arginine methyl ester; LD 1400W = low-dose 1400W; HD 1400W = high-dose 1400W; Non I 1400W = nonischemic 1400W; Non I Control = nonischemic control.)

 
The baseline, postintervention, and percent recovery data for left ventricular developed pressure are reported in Table 3. As was the case with CF, there were no between-group differences at baseline. Left ventricular developed pressure was significantly reduced among all groups undergoing ischemia versus the two nonischemic groups (Non I Control, Non I 1400W). There were no significant differences among the ischemic or nonischemic subsets. Figure 3 represents the entire 20-minute postintervention perfusion period.


View this table:
[in this window]
[in a new window]
  		Table 3. Left Ventricular Developed Pressure Before Intervention (Ischemia + Drug or Drug Alone), After 20 Minutes of Postintervention Perfusion, and Percent Recoverya

 


View larger version (30K):
[in this window]
[in a new window]
  		Fig 3. Left ventricular developed pressure during postintervention perfusion. (L-NAME = N{omega}-nitro-L-arginine methyl ester; LD 1400W = low-dose 1400W; HD 1400W = high-dose 1400W; Non I 1400W = nonischemic 1400W; Non I Control = nonischemic control.)

 
Contractility, or the first derivative of the left ventricular pressure, is reported in Table 4. Although there was not a significant increase in contractility between the four groups that underwent ischemia–reperfusion, there is a clear trend toward improved function in the LD 1400W and HD 1400W groups that approaches that of the nonischemic groups.


View this table:
[in this window]
[in a new window]
  		Table 4. Left Ventricular Contractility Before Intervention (Ischemia + Drug or Drug Alone), After 20 Minutes of Postintervention Perfusion, and Percent Recoverya

 
Biochemical data
Table 5 lists the results of the biochemical assays that were performed. There was a statistically significant difference in MPO levels between the L-NAME group and the HD 1400W, Non I 1400W, and Non I Control groups. The Non I Control group had cGMP levels significantly higher than all other groups except Non I 1400W.


View this table:
[in this window]
[in a new window]
  		Table 5. Results of Biochemical Assaysa

 

   Comment
Top
 Abstract
 Introduction
 Material and methods
 Results
 Comment
Acknowledgments
 References
 
Knowledge of the physical locations and functions of the various isoforms of NOS within the heart is necessary when considering manipulations of the L-arginine–NOS pathway. Virtually ubiquitous throughout the heart, eNOS is found in the endothelium of both the endocardium and the coronary vasculature, in myocytes, and in specialized cardiac conduction tissue [10]. Although its role is multifaceted, its primary function is the regulation of coronary blood flow [10]. Although iNOS is not significantly expressed by any tissues within the heart in the normal state, with appropriate stimulation (as discussed subsequently), iNOS may be manifested by a variety of tissues and cells within the heart. Endocardial endothelium, infiltrating inflammatory cells, vascular smooth muscle, fibroblasts, cardiac myocytes, and microvascular endothelium have all been shown in vitro and in vivo to produce iNOS after appropriate stimuli [10]. Among these cell types, cardiac myocytes and the microvascular endothelium probably account for the majority of NO production after induction of iNOS [10]. The role of iNOS is a topic of considerable and persistent debate. The production of large amounts of NO after induction of iNOS has been shown to be detrimental in a variety of ways, including decreased contractile function, a decreased rate of spontaneous contraction, and even apoptosis in cardiac myocytes [10].

Determining the relative contributions of eNOS and iNOS to the pathogenesis of ischemia–reperfusion injury has been made more difficult by the lack of truly specific inhibitors of the various isoforms. 1400W is a highly specific inhibitor of iNOS. Aminoguanidine, frequently used as a specific inhibitor of iNOS is, at best, 30 times more selective for iNOS versus constitutive, or eNOS, whereas 1400W is more than 5,000 times more selective for iNOS [14].

In this investigation 1400W was used to demonstrate that a highly specific inhibitor of iNOS improves CF when given during reperfusion, but has no effect when given to hearts that have undergone continuous perfusion. From an examination of the CF data (Fig 2), it would appear that the effects of 1400W are not caused by some unsuspected, intrinsic vasodilating property unrelated to iNOS inhibition, as the two nonischemic groups demonstrated virtually identical CFs throughout the 20-minute period. Furthermore, it is unlikely that 1400W was acting as a substrate for eNOS or iNOS. Detailed studies conducted by the group that synthesized 1400W could not demonstrate any activity for 1400W as a substrate of iNOS [14]. It is also unlikely that 1400W inhibited eNOS. Inhibition of eNOS has been shown in several studies to be associated with a decrease in CF and an increase in neutrophil accumulation, contrary to what was seen in this experiment [3, 4, 13]. And, as was shown previously, eNOS has a low, rapidly reversible affinity for 1400W [14].

The net effects of administration of 1400W, increased CF and decreased neutrophil accumulation, were similar to observed effects of administration of exogenous NO or of L-arginine, the substrate for NOS (all isoforms) [2–5, 13]. It is possible, therefore, that by inhibiting iNOS we have provided, in effect, additional substrate for the resident eNOS. Increased eNOS production of NO would be expected to promote coronary vasodilation and to decrease neutrophil accumulation. Several studies have demonstrated the presence of iNOS in myocardium [18–20]. In our experimental protocol, the isolated hearts were exposed to 30 minutes of ischemia followed by 20 minutes of perfusion. This 50 minutes is adequate for the early demonstration of iNOS activity, which would then be inhibited by the administration of 1400W [20].

Myeloperoxidase levels were lower in hearts treated with HD 1400W during reperfusion compared with the other ischemic groups (Table 5). This difference was significant when compared with the L-NAME group. Inhibition of iNOS may account for this effect. Selective inhibition of iNOS could, as theorized previously, in effect provide additional substrate for eNOS. Nitric oxide, produced by the vascular endothelium, exerts an inhibitory effect on neutrophils that compromises their ability to attach to the endothelium [21]. Interestingly, aminoguanidine has been shown to promote neutrophil adhesion to venules in the rat mesentery, an effect that correlated with the effect of L-NAME and was reversed by the addition of L-arginine [22]. This further illustrates the need for specific inhibitors to dissect the varying roles of iNOS and eNOS.

Left ventricular developed pressure was essentially the same within the ischemic groups and within the two nonischemic groups (Table 3). Contractility, though found to be statistically nonsignificant, demonstrated a clear trend toward improvement in the groups treated with 1400W, based on the percent recovery of baseline values (Table 4). Previous reports have demonstrated reduced contractility in both isolated cardiac myocytes and in whole-organ models in response to iNOS stimulation [7, 9, 23]. In some studies, this has been found to be linked to increased cGMP levels thought to be mediated by NO [24, 25]. In an effort to explore this further, all hearts were assayed for cGMP content using a radioimmunoassay [17]. All the ischemic groups demonstrated decreased tissue levels of cGMP relative to the nonischemic controls, with a significant difference between the Non I Control group and all four ischemic groups. Thus, no conclusions could be drawn from this data.

We have shown that iNOS inhibition increased CF significantly. It also reduced MPO significantly, suggesting an effect on neutrophils. It may be that iNOS inhibition increases the available substrate for eNOS, thus increasing the amount of NO produced by this isoform and accounting for the findings we have demonstrated. Clearly both eNOS and iNOS have a major role in the coronary circulation. Augmentation of eNOS while inhibiting iNOS could ultimately be used clinically after ischemia–reperfusion.


   Acknowledgments
Top
 Abstract
 Introduction
 Material and methods
 Results
 Comment
 Acknowledgments
References
 
We express our grateful appreciation to Mr. Anthony J. Herring for his invaluable technical assistance. We also thank Mr. Jeffery Oplinger for synthesizing the 1400W.

This research was supported by a National Research Service Award (Fellowship No. 1 F32 HL09558-01A1) granted by the National Heart, Lung, and Blood Institute of the National Institutes of Health.


   References
Top
 Abstract
 Introduction
 Material and methods
 Results
 Comment
 Acknowledgments
 References
 

  1. Williams M.W., Taft C.S., Ramnauth S., et al. Endogenous nitric oxide (NO) protects against ischemia–reperfusion injury in the rabbit. Cardiovasc Res 1995;30:79-86.[Medline]
  2. Wang Q.D., Morcos E., Wiklund P., et al. L-Arginine enhances functional recovery and Ca++ dependent nitric oxide synthase activity after ischemia and reperfusion in the rat heart. J Cardiovasc Pharmacol 1997;29:291-296.[Medline]
  3. Engelman D.T., Watanabe M., Engelman R.M., et al. Constitutive nitric oxide release is impared after ischemia and reperfusion. J Thorac Cardiovasc Surg 1995;110:1047-1053.[Abstract/Free Full Text]
  4. Vinten-Johansen J., Sato H., Zhao Z.Q. The role of nitric oxide and NO-donor agents in myocardial protection from surgical ischemic–reperfusion injury. Int J Cardiol 1995;50:273-281.[Medline]
  5. Carrier M., Khalil A., Tourigny A., et al. Effect of L-arginine on metabolic recovery of the ischemic myocardium. Ann Thorac Surg 1996;61:1651-1657.[Abstract/Free Full Text]
  6. Wang P., Zweier J.L. Measurement of nitric oxide and peroxynitrite generation in the postischemic heart. J Biol Chem 1996;27:29223-29230.
  7. Matheis G., Sherman M.P., Buckberg G.D., et al. Role of L-arginine–nitric oxide pathway in myocardial reoxygenation injury. Am J Physiol 1992;262:H616-H620.
  8. Lefer D.J., Scalia R., Campbell B., et al. Peroxynitrite inhibits leukocyte–endothelial cell interactions and protects against ischemia–reperfusion in rats. J Clin Invest 1997;99:684-691.[Medline]
  9. Schulz R., Wambolt R. Inhibition of nitric oxide synthesis protects the isolated working rabbit heart from ischemia–reperfusion injury. Cardiovasc Res 1995;30:432-439.[Medline]
  10. Kelly R.A., Balligand J.L., Smith T.W. Nitric oxide and cardiac function. Circ Res 1996;79:363-380.[Free Full Text]
  11. Akiyama K., Suzuki H., Grant P., et al. Oxidation products of nitric oxide, NO2 and NO3, in plasma after experimental myocyte infarction. J Mol Cell Cardiol 1997;29:1-9.[Medline]
  12. Mauney M.C., Cope J.T., Binns O.A.R., et al. Non-heart-beating donors: a model of thoracic allograft injury. Ann Thorac Surg 1996;62:54-62.[Abstract/Free Full Text]
  13. Hoshida S., Yamashita N., Igarashi J., et al. Nitric oxide synthase protects the heart against ischemia–reperfusion injury in rabbits. J Pharmacol Exp Ther 1995;274:413-418.[Abstract/Free Full Text]
  14. Garvey E.P., Oplinger J.A., Furfine E.S., et al. 1400W is a slow, tight binding, and highly selective inhibitor of inducible nitric-oxide synthase in vitro and in vivo. J Biol Chem 1997;272:4959-4963.[Abstract/Free Full Text]
  15. Loscalzo J., Welch G. Nitric oxide and its role in the cardiovascular system. Prog Cardiovasc Dis 1995;38:87-104.[Medline]
  16. Lohmann S.M., Fischmeister R., Walter U. Signal transduction by cGMP in heart. Basic Res Cardiol 1991;86:503-514.[Medline]
  17. Brooker G., Terasaki W.L., Price M.G. Gammaflow: a completely automated radioimmunoassay system. Science 1976;194:270-276.[Free Full Text]
  18. Bateson A.N., Jakiwczyk O.M., Schulz R. Rapid increase in inducible nitric oxide synthase gene expression in the heart during endotoxemia. Eur J Pharmacol 1996;303:141-144.[Medline]
  19. Balligand J.L., Ungureanu-Longrois D., Simmons W.L., et al. Cytokine-inducible nitric oxide synthase (iNOS) expression in cardiac myocytes. J Biol Chem 1994;269:27580-27588.[Abstract/Free Full Text]
  20. Schulz R., Nava E., Moncada S. Induction and potential biological relevance of a Ca2+-independent nitric oxide synthase in the myocardium. Br J Pharmacol 1992;105:575-580.[Medline]
  21. Ma X.L., Weyrich A.S., Lefer D.J., et al. Diminished basal nitric oxide release after myocardial ischemia and reperfusion promotes neutrophil adherence to coronary endothelium. Circ Res 1993;72:403-412.[Abstract/Free Full Text]
  22. Lopez-Belmonte J., Whittle B.J. Aminoguanidine-provoked leukocyte adherence to rat mesenteric venules: role of constitutive nitric oxide synthase inhibition. Br J Pharmacol 1995;116:2710-2714.[Medline]
  23. Sun X., Wei S., Szabo C., et al. Depression of the ionotropic action of isoprenaline by nitric oxide synthase induction in rat isolated hearts. Eur J Pharmacol 1997;320:29-35.[Medline]
  24. Kinugawa K., Kohmoto O., Yao A., et al. Cardiac inducible nitric oxide synthase negatively modulates myocardial function in cultured rat myocytes. Am J Physiol 1997;272:H35-H47.
  25. Balligand J.L., Ungureanu D., Kelly R.A., et al. Abnormal contractile function due to induction of nitric oxide synthesis in rat cardiac myocytes follows exposure to activated macrophage-conditioned medium. J Clin Invest 1993;91:2314-2319.



This article has been cited by other articles:


Home page
 Am. J. Physiol. Lung Cell. Mol. Physiol.Home page
D. J. Vaughan, T. V. Brogan, M. E. Kerr, S. Deem, D. L. Luchtel, and E. R. Swenson
Contributions of nitric oxide synthase isozymes to exhaled nitric oxide and hypoxic pulmonary vasoconstriction in rabbit lungs
Am J Physiol Lung Cell Mol Physiol, May 1, 2003; 284(5): L834 - L843.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
L. Zhang, C. G. Looney, W.-N. Qi, L.-E. Chen, A. V. Seaber, J. S. Stamler, and J. R. Urbaniak
Reperfusion injury is reduced in skeletal muscle by inhibition of inducible nitric oxide synthase
J Appl Physiol, April 1, 2003; 94(4): 1473 - 1478.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
S. Kanno, P. C. Lee, Y. Zhang, C. Ho, B. P. Griffith, L. L. Shears II, and T. R. Billiar
Attenuation of Myocardial Ischemia/Reperfusion Injury by Superinduction of Inducible Nitric Oxide Synthase
Circulation, June 13, 2000; 101(23): 2742 - 2748.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
G. Cotter, E. Kaluski, A. Blatt, O. Milovanov, Y. Moshkovitz, R. Zaidenstein, A. Salah, D. Alon, Y. Michovitz, M. Metzger, et al.
L-NMMA (a Nitric Oxide Synthase Inhibitor) is Effective in the Treatment of Cardiogenic Shock
Circulation, March 28, 2000; 101(12): 1358 - 1361.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
Z. Yang, B. Zingarelli, and C. Szabo
Crucial Role of Endogenous Interleukin-10 Production in Myocardial Ischemia/Reperfusion Injury
Circulation, March 7, 2000; 101(9): 1019 - 1026.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Patrick E. Parrino
Robert C. King
Curtis G. Tribble
Irving L. Kron
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Parrino, P. E.
Right arrow Articles by Kron, I. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Parrino, P. E.
Right arrow Articles by Kron, I. L.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ANN THORAC SURG ASIAN CARDIOVASC THORAC ANN EUR J CARDIOTHORAC SURG
J THORAC CARDIOVASC SURG ICVTS ALL CTSNet JOURNALS