AJP - Heart Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 288: H2323-H2331, 2005. First published January 6, 2005; doi:10.1152/ajpheart.00822.2004
0363-6135/05 $8.00
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
288/5/H2323    most recent
00822.2004v1
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 ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (5)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chen, Y.
Right arrow Articles by Morgan, J. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chen, Y.
Right arrow Articles by Morgan, J. P.

Cocaine and catecholamines enhance inflammatory cell retention in the coronary circulation of mice by upregulation of adhesion molecules

Yu Chen,* Qingen Ke,* Yong-Fu Xiao, Guifu Wu, Emel Kaplan, Thomas G. Hampton, Sohail Malek, Jiang-Yong Min, Ivo Amende, and James P. Morgan

Cardiovascular Division, Department of Medicine, The Charles A. Dana Research Institute and Harvard-Thorndike Laboratories, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts

Submitted 13 August 2004 ; accepted in final form 3 January 2005


   ABSTRACT
TOP
 ABSTRACT
MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
 REFERENCES
 
Cocaine treatment of mice with viral myocarditis significantly increases neutrophil infiltration into the myocardium and exacerbates the inflammatory response. The mechanisms of these effects are unknown; however, it may be that cocaine increases circulating catecholamines and consequently increases inflammatory cell adhesion to the coronary endothelium. Here, we examined the hypothesis that cocaine enhances inflammatory cell infiltration via catecholamine-induced upregulation of cell adhesion molecule (CAM) expression in adult BALB/c mouse hearts. Intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelial leukocyte adhesion molecule-1 (E-selectin), and leukocyte adhesion molecule-1 (L-selectin) were detected by gene array analysis, RT-PCR, Western blotting, and immunohistochemical staining. CAMs were significantly upregulated in cocaine-treated mouse hearts. {beta}-Adrenergic stimulation with epinephrine also upregulated CAM expression, confirming the effects obtained with cocaine. {beta}-Adrenergic blockade with propranolol inhibited epinephrine-induced CAM expression. In hearts infused with polymorphonuclear neutrophils (PMN), an increased adhesion of PMN to the coronary endothelium was observed in cocaine-treated and epinephrine-treated mouse hearts compared with control hearts. Blocking antibodies against ICAM-1, E-selectin, and L-selectin significantly inhibited epinephrine-enhanced PMN adhesion, whereas anti-VCAM-1 had lesser effects. Our findings suggest that cocaine-induced neutrophil infiltration is mediated by {beta}-adrenergic stimulation through upregulation of CAM expression, which enhances PMN adhesion. Conversely, {beta}-adrenergic blockade with propranolol inhibits the effects of cocaine and epinephrine on CAM expression and decreases PMN adhesion to the coronary endothelium. These observations may be of significance for the development of preventative and therapeutic approaches to patients with cocaine- or catecholamine-induced myocarditis.

epinephrine; propranolol; cell adhesion molecules; polymorphonuclear neutrophils; heart perfusion

INFLAMMATION IS A PROTECTIVE response in vascularized tissue designed to rid the organism of both the initial cause of cell injury (i.e., microbes, toxins) and the consequences of such injury (i.e., necrotic cells and tissues). A critical function of inflammation is the delivery of neutrophils to the site of injury, to ingest offending agents, engulf and kill bacteria and other microbes, and degrade necrotic tissues and foreign antigens. Neutrophils also release enzymes, chemical mediators, and toxic oxygen radicals, which may prolong and enhance the inflammatory response.

Neutrophils. Neutrophil adhesion occurs by transient attachment of the neutrophils to endothelial surfaces. It is a multistep process, which includes the initial phase of selectin-mediated attachment and rolling and the subsequent integrin-mediated firm adherence (14, 25). Chemical mediators, including certain cytokines, can affect the surface expression or binding properties of cell adhesion molecules (CAMs). Neutrophil-endothelial adhesion molecules belong to four molecular families, including selectins, immunoglobulins, integrins, and mucin-like glycoproteins. Endothelial leukocyte adhesion molecule-1 (E-selectin), ICAM-1, and VCAM-1 are three of the most important molecules associated with neutrophil-endothelial adhesion (22). Leukocyte adhesion molecule-1 (L-selectin) is primarily expressed by neutrophils and monocytes and mediates neutrophil rolling with subsequent integrin-mediated firm adherence (30). Several different mechanisms modulate neutrophil adhesion during inflammation, including redistribution to the cell surface of prejoined adhesion molecules, the synthesis and surface expression of new adhesion molecules, and increased CAM binding avidity (4). There is strong evidence that neutrophil adherence to the endothelium is of central importance in the inflammatory response to infections (16, 27).

CAM expression. There is evidence to support a role for sympathetic stimulation as a mediator of enhanced CAM expression, although its importance remains controversial (7, 20, 24). Gan et al. (8) showed that cocaine enhances brain endothelial adhesion molecule expression and neutrophil migration. Buemi et al. (2) reported a statistically significant correlation between soluble adhesion molecules (ICAM-1, VCAM-1, and E-selectin) and plasma concentrations of epinephrine and norepinephrine at rest and after stimulation using the cold pressor test in humans. At the cellular level, Braun et al. (1) showed that the expression of CAMs on human smooth muscle cells induced by cytokines is differentially modulated by the action of adenylate cyclase. Rainer et al. (21) showed that epinephrine enhances L-selectin expression on monocytes and that {beta}-blockade may have an inhibitory role for certain aspects of leukocyte trafficking.

It has been shown in a murine model of viral myocarditis that cocaine administration enhances inflammation and neutrophil infiltration into the myocardium (11, 33). The precise mechanisms of these effects remain unclear, although the effects of cocaine probably include neutrophil homing to the heart, cell adhesion to the coronary endothelium, and cell transmigration across the endothelial membrane into the cardiac interstitium. Cocaine is also known to increase catecholamine levels in the plasma of animals and patients (3, 9, 18, 19, 29).

{beta}-Adrenergic stimulation. It has been reported that {beta}-adrenergic stimulation may enhance CAM expression in the endothelial cell membrane. In particular, {beta}-adrenergic stimulation has been shown to enhance CAM expression of endothelial cells (8, 21). We propose, therefore, that endothelial CAM expression is enhanced by {beta}-adrenergic stimulation and consequently increases neutrophil adhesion to the coronary endothelium. This in turn is a potent stimulus that elicits an increase of inflammation in cocaine-treated mouse hearts.

The present study was designed to test the hypothesis that cocaine and catecholamines enhance inflammatory cell retention in the coronary endothelium of mice by upregulation of adhesion molecules. Our hypothesis is supported by our findings that neutrophil adhesion is enhanced in cocaine- and epinephrine-treated mouse hearts. Blocking antibodies against CAMs attenuated these effects, lending further support to our hypothesis.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 GRANTS
 REFERENCES
 
Animals. This study was performed with the approval of the Institutional Animal Care and Use Committee of Beth Israel Deaconess Medical Center. Adult BALB/c mice (8 wk) of each sex were purchased from the Jackson Laboratory. Handling and care of mice were consistent with federal and institutional guidelines. Animals were housed at room temperature on a 14:10-h light-dark cycle, with food and water provided ad libitum. Human blood collection was obtained under the agreements with the Institutional Committee of Beth Israel Deaconess Medical Center.

TNF-{alpha} and IL-6 expression. Epinephrine-treated hearts and saline-treated control hearts (100 mg/heart, n = 3) were homogenized in 1 ml of PBS and centrifuged at 1,000 g for 10 min at 4°C. The concentrations of TNF-{alpha} and IL-6 in the supernatant were determined by commercial ELISA kits (Genzyme, Framingham, MA).

Gene expression analysis. To determine whether cocaine affects gene expression of CAMs, heart tissue was obtained from three cocaine-treated mice (30 mg·kg–1·day–1 for 2 wk, provided intraperitoneally) and three saline-treated control mice. Total RNA was extracted from the heart tissue by Tri-Reagent (Sigma, St. Louis, MO). Two micrograms of RNA were used to perform adhesion molecules analyses via GEArray Q Series mouse extracellular matrix and adhesion molecule gene array (SuperArray Bioscience), which contains 96 genes encoding cell adhesion and extracellular matrix proteins. Analyses were performed according to the protocol of the SuperArray Bioscience manufacturer, and the data were analyzed with a GEArray analyzer. Gene comparisons were expressed as a ratio adjusted for background and housekeeping gene expression. A greater than twofold increase in the gene signal intensity of CAMs was considered significant. Genes of CAMs with a signal intensity less than twofold were not further studied.

CAM mRNA analysis. RT-PCR was performed in 18 mouse hearts to determine the expression of CAM mRNA (n = 3 in each of the following groups): saline-treated control, cocaine treated (30 mg·kg–1·day–1 for 2 wk), epinephrine treated (3 mg/kg for 6 h), cocaine plus propranolol treated (3 mg/kg for 2 wk), epinephrine plus propranolol treated (3 mg/kg for 6 h), and propranolol only treated (3 mg/kg for 6 h). Saline and drugs were administered intraperitonially. Total RNA was extracted from heart tissue by Tri-Reagent. A single-strand cDNA as a PCR template was synthesized with oligo(dT)12–18 primer and Moloney murine leukemia virus reverse transcriptase (Invitrogen, Carlsbad, CA). cDNA fragments of ICAM-1, VCAM-1, and E- and L-selectins were amplified with Taq DNA polymerase (Invitrogen).

The sequences of the sense and antisense primers for CAMs were designed via the Biology WorkBench (National Laboratory for Computational Science and Engineering, University of California, San Diego, CA). These were as follows: for ICAM-1, sense = 5'-CTGGCTGTCACAGAACAGGA-3' and antisense = 5'-AAAGTAGGTGGGGAGGTGCT-3' (559 bp product length); for VCAM-1, sense = 5'-CCCAAGGATCCAGAGATTCA-3' and antisense = 5'-TAAGGTGAGGGTGGCATTTC-3' (489 bp product length); for E-selectin, sense = 5'-AGCTACCCATGGAACACGAC-3' and antisense = 5'-TGCAAGCTAAAGCCCTCATT-3' (623 bp product length); and for L-selectin, sense = 5'-CTCCTCCTAATTTCCCCTCG-3' and anti-sense = 5'-TCAATGCAGGAGATTTTCCC-3' (480 bp product length). Reaction conditions were as follows: 1 x (94°C for 2 min), 30 x (94°C for 1 min, 54°C for 1 min, and 72°C for 2 min), and 1 x (72°C for 7 min). Products were visualized and analyzed by electrophoresis on a 1% agarose gel containing ethidium bromide. The expression of 18S RNA was referenced to an endogenous internal standard. Densitometry was performed to quantify CAM mRNA expression. Results are expressed as a percentage of control.

Protein analysis. Protein was determined in 18 mouse hearts by Western blotting (n = 3 in each group): saline-treated control, cocaine treated (30 mg·kg–1·day–1, 2 wk), epinephrine treated (3 mg/kg, 6 h), cocaine plus propranolol treated (3 mg/kg, 2 wk), epinephrine plus propranolol treated (3 mg/kg, 6 h), and propranolol only treated (3 mg/kg, 6 h). Hearts were homogenized in RIPA buffer (Boston Bioproducts). Sixty micrograms of protein in an equal volume of loading buffer (Boston Bioproducts) were boiled and separated by 4–15% SDS-PAGE ready gel and transferred to a polyvinylidene difluoride membrane (Bio-Rad Laboratories, Hercules, CA) for staining. The nonspecific binding sites of protein were blocked in PBS containing 1% BSA, 1.5% nonfat dry milk, 1% horse serum, and 0.1% Tween 20 for 1 h. The membrane was then incubated at 4°C overnight with primary antibodies against either ICAM-1 (R&D Systems, Minneapolis, MN), VCAM-1 (Chemicon, Temecula, CA), E-selectin (Pharmingen, San Diego, CA), or L-selectin (Research Diagnostics, Flanders, NJ) (diluted 1:500). The antibody-positive proteins were conjugated with horseradish peroxidase-linked secondary antibodies (diluted 1:2,000) and visualized with enhanced chemiluminescence luminol reagent (Santa Cruz Biotechnology, Santa Cruz, CA). To ensure a similar amount of protein in each sample, the polyvinylidene difluoride membranes were "stripped off," reprobed with GAPDH, developed with horseradish peroxidase-conjugated secondary antibodies, and visualized by enhanced chemiluminescence. Densitometry was performed to quantify CAM protein expression. Results are expressed as a percentage of control values.

Immunohistochemistry. Immunohistochemistry was performed in sections of 24 hearts to determine CAM expression by using antibodies against ICAM-1, VCAM-1, E-selectin, and L-selectin (n = 6 in each of the following groups): saline-treated control, cocaine treated (30 mg·kg–1·day–1, 2 wk), epinephrine treated (3 mg/kg, 6 h), and propranolol only treated (3 mg/kg, 6 h). Xylene (Sigma) was used to remove paraffin from the paraffin-embedded heart sections; this was followed by dehydration with 100, 95, 80, and 40% ethanol (5 min for each procedure). The sections were boiled in 10 mM sodium citrate buffer (pH 6.0) for 1 min and then cooled down to unmask the antigen. The sections were then incubated in 1% H2O2 for 10 min at room temperature to block endogenous peroxidase. Antibodies against adhesion molecules ICAM-1, VCAM-1, and E-selectin (diluted 1:50) were incubated overnight with sections at 4°C. The immunologic reaction was obtained using Vectastain Elite ABC reagent (Vector Laboratories, Burlingame, CA) and visualized in a solution containing diaminobenzidine, which produced a yellow-brown color of the antibody-positive cells. Nuclei were stained with hematoxylin. Frozen heart sections were incubated overnight with an antibody against L-selectin (diluted 1:50) at 4°C. The procedure was the same as that performed in paraffin-fixed samples. Wide-field images were obtained with a x20 objective microscope (model E-400, Nikon) equipped with a back-illuminated charge-coupled device camera (model Y-FL, Nikon) and processed with Spot 4.0 software (Diagnostic Instrument). Image-Pro Plus (MediaCybernetics) image analysis was performed to quantify the immunoreactivity of CAMs. Positively stained cells were counted in each section at a magnification of x50. Results are presented as the percentage of CAM-positive cells (dark brown staining) within the image. To determine whether MAPK pathways of polymorphonuclear neutrophils (PMN) were involved in cocaine- and epinephrine-treated hearts, the degrees of phosphorylation of JNK, ERK, and p38 MAPK were also analyzed.

PMN isolation. Human PMN were obtained from five normal healthy volunteers (24–50 yr old) on the day when the mouse heart perfusion studies were performed. Informed consent was obtained. PMN were isolated by sedimentation of plasma using Ficoll-Paque (Amersham Bioscience) as described by Tyagi et al. (28). PMN purity was 94–98%, determined by microscopically identifying cellular morphology and by hematoxylin staining.

Isolated heart perfusion. Hearts from adult BALB/c mice (~2 mo old) were perfused in vitro as previously described (10). Briefly, the aorta was cannulated, and the heart was perfused at 37°C in a modified Krebs buffer containing (in mM) 118 NaCl, 4.7 KCl, 1.2 KH2PO4, 1.5 CaCl2, 1.2 MgCl2, 23 NaHCO3, 10 dextrose, and 0.3 pyruvate and 0.5% BSA and then gassed with 95% O2-5% CO2 and adjusted to a pH of 7.4. A flow pump (Masterflex model 7013-20, Cole-Parmer Instruments) provided constant coronary perfusion at a rate of 2.5 ml/min. An incision was made at the root of the pulmonary artery to drain coronary effluent.

PMN infusion. Human PMN were diluted to 3 x 105 cells/ml in modified Krebs buffer (see PMN isolation above). One milliliter of the solution containing PMN was infused for 1 min into the coronary system of 36 hearts (n = 6 in each group of the following groups) via an additional tubing connected to the perfusion line using an infusion pump (model PHD2000, Harvard Apparatus): saline-treated control, cocaine treated (30 mg·kg–1·day–1, 2 wk), epinephrine treated (3 mg/kg, 6 h), cocaine plus propranolol treated (3 mg/kg, 2 wk), epinephrine plus propranolol treated (3 mg/kg, 6 h), and propranolol only treated (3 mg/kg, 6 h).

Adhesion molecule antibodies. We tested whether antibodies against CAMs affect PMN adhesion to the coronary endothelium in epinephrine-treated hearts. Epinephrine-treated hearts (3 mg/kg, 6 h, n = 18) were perfused for 15 min with antibodies (5 µg/ml) against ICAM-1, VCAM-1, and E -selectin (n = 6 in each group) followed by infusion of 1 ml PMN for 1 min. It has been shown that L-selectin is widely distributed on neutrophils in the blood and participates in many neutrophil-endothelial cell interactions (22, 30). In six additional epinephrine-treated hearts (n = 6), a blocking antibody (5 µg/ml) against L-selectin was administered followed by the infusion of 1 ml PMN. PMN were pretreated with anti-L-selectin (5 µg/ml) for 15 min. Six epinephrine-treated hearts (3 mg/kg, 6 h), not treated with specific antibodies against CAMs, served as control. We used the following blocking antibodies against CAMs: for ICAM-1, polyclonal mouse ICAM-1 extracellular domain-specific goat IgG (goat IgG isotype; R&D Systems); for VCAM-1, monoclonal rat anti-mouse VCAM-1 (M/K-2 clone, rat IgG1{kappa} isotype; Chemicon); for E-selectin, monoclonal rat anti-mouse E-selectin (10E9.6 clone, rat IgG2{alpha}{kappa} isotype; Research Diagnostics); and for L-selectin, monoclonal rat anti-mouse L-selectin (MEL 14 clone, rat IgG2{alpha}{kappa} isotype; Research Diagnostics). All of these antibodies are directed against murine CAMs. We used nonbinding, isotype-matched antibodies [goat IgG for ICAM-1, rat IgG1{kappa} for VCAM-1, rat IgG2{alpha} for E-selectin, and rat IgG2{alpha}{kappa} for L-selectin (n = 6 in each group)] to confirm the effects of the specific antibodies against CAMs.

PMN adhesion analysis. Coronary effluent was continuously collected during the 1-min infusion of PMN and 2 min after the infusion to determine PMN output. Coronary effluent was not collected beyond 2 min because a negligible number (<1%) of PMN were detected after 3 min of PMN infusion (n = 6). In all hearts, 1 ml of the solution containing PMN was collected exogenously for 1 min before infusion into the coronary circulation to determine the PMN content. The percentage of PMN adhering to the coronary endothelium was calculated as follows: adhesion (%) = [1 – (PMN output/PMN input)] x 100.

JNK and ERK inhibition. To further assess the role of JNK and ERK in PMN adhesion, specific inhibitors for studying signaling pathways were used in cocaine- and epinephrine-treated hearts. SP-600125 (10 µM), an inhibitor of JNK (Calbiochem), PD-98059 (10 µM), an inhibitor of ERK (Calbiochem), or both of them together were administered to cocaine- and epinephrine-treated hearts 10 min before PMN perfusion (n = 3 in each group). p38 was not further studied because no phosphorylation of p38 MAP kinase was found.

Data analysis. Values are presented as means ± SD. Results between two individual groups were compared by the unpaired Student's t-test. Data from more than two experimental groups were statistically compared by one-way ANOVA. Differences were considered significant at P < 0.05.


   RESULTS
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
DISCUSSION
 GRANTS
 REFERENCES
 
Epinephrine does not increase cytokine expression. We did not detect an expression of TNF-{alpha} and IL-6 in epinephrine-treated hearts under the conditions of our experiments.

Cocaine upregulates mRNA expression of CAMs. CAMs such as immunoglobulins, selectins, and integrins are required for neutrophil transmigration across the endothelium during most inflammatory responses (20). We used gene array analysis in three cocaine-treated and in three saline-treated control mouse hearts to determine whether cocaine affects gene expression of CAMs. We obtained gene signals of the following CAMs: ICAM-1, VCAM-1, platelet endothelial cell adhesion molecule 1 (PECAM-1), E-selectin, L-selectin, {alpha}5-integrin, {alpha}7-integrin, {alpha}x-integrin, {beta}1-integrin, {beta}5-integrin, and {beta}6-integrin (Fig. 1). Cocaine (30 mg·kg–1·day–1 for 2 wk) significantly enhanced the expression of ICAM-1 (2.4 ± 0.2-fold, P < 0.05), VCAM-1 (3.0 ± 0.3-fold, P < 0.05), E-selectin (2.4 ± 0.3-fold, P < 0.05), and L-selectin (5.5 ± 0.5-fold, P < 0.05) compared with control hearts. PECAM-1 (1.3 ± 0.2-fold), P-selectin (1.5 ± 0.4-fold), {alpha}5-integrin (1.4 ± 0.3-fold), {alpha}7-integrin (1.2 ± 0.5-fold), {alpha}x-integrin (1.2 ± 0.2-fold), {beta}1-integrin (1.1 ± 0.3-fold), {beta}5-integrin (1.2 ± 0.3-fold), and {beta}6-integrin (1.3 ± 0.2-fold) showed a slight increase in cocaine-treated hearts compared with control hearts. PECAM-1, P-selectin, and integrins were not further studied because the gene signal intensity was <2.0-fold. We used RT-PCR to validate gene expression identified by gene array. ICAM-1, VCAM-1, and E- and L-selectin mRNA levels were significantly upregulated in cocaine-treated and epinephrine-treated hearts compared with saline-treated control hearts: 1.5 ± 0.2- and 1.5 ± 0.1-fold for ICAM-1, 1.6 ± 0.2- and 1.6 ± 0.2-fold for VCAM-1, 4.4 ± 1.3- and 3.6 ± 0.9-fold for E-selectin, and 3.2 ± 0.5- and 2.5 ± 0.5-fold for L-selectin, respectively (Fig. 2). Pretreatment with propranolol significantly attenuated CAM mRNA upregulation in cocaine- and epinephrine-treated hearts. P < 0.05 in all comparisons of cocaine- and epinephrine-treated hearts with saline-treated control hearts (n = 3 in each group). RT-PCR confirmed the changes of gene expression of CAMs identified by gene array.



View larger version (59K):
[in this window]
[in a new window]
  		Fig. 1. Gene array of cell adhesion molecules (CAMs). RNA was extracted from 3 cocaine-treated (30 mg·kg–1·day–1 for 2 wk) and 3 saline-treated control mouse hearts. Two micrograms of RNA were used to generate the gene array. A >2-fold increase of the gene signal intensity of CAMs compared with control hearts was considered significant. Cocaine treatment significantly enhanced the expression of ICAM-1 (2.4 ± 0.2-fold, P < 0.05), VCAM-1 (3.0 ± 0.3-fold, P < 0.05), E-selectin (2.4 ± 0.3-fold, P < 0.05), and L-selectin (5.5 ± 0.5-fold, P < 0.05) compared with control hearts. Platelet endothelial cell adhesion molecule 1, P-selectin, and integrins, with a signal intensity of <2-fold, were not further studied.

 


View larger version (42K):
[in this window]
[in a new window]
  		Fig. 2. A: RT-PCR analysis of CAM mRNA. CAM mRNA was isolated from control, cocaine-treated (30 mg·kg–1·day–1, 2 wk), epinephrine-treated (3 mg/kg, 6 h), cocaine plus propranolol-treated (3 mg·kg–1·day–1, 2 wk), epinephrine plus propranolol-treated (3 mg/kg, 6 h), and propranolol only-treated mouse hearts (n = 3 in each group). Densitometry was used to quantify CAM mRNA expression. B: quantitative analysis of mRNA levels. CAM mRNA intensity was normalized to the relative intensity of 18S RNA. *P < 0.05 compared with control mouse hearts.

 
Propranolol attenuates cocaine- and epinephrine-induced upregulation of CAM protein expression. Western blot analysis was performed to determine the protein expression of CAM. The protein expression of CAMs significantly increased in cocaine- and epinephrine-treated hearts compared with control hearts: 1.7 ± 0.2- and 1.5 ± 0.2-fold for ICAM-1, 2.2 ± 0.3- and 2.1 ± 0.4-fold for VCAM-1, 3.7 ± 0.5- and 3.0 ± 0.3-fold for E-selectin, and 3.8 ± 0.4- and 3.2 ± 0.2-fold for L-selectin, respectively (Fig. 3). Propranolol administration significantly attenuated both cocaine- and epinephrine-induced CAM protein expression (Fig. 3). The P value was <0.05 in all comparisons of cocaine-treated and epinephrine-treated hearts to saline-treated control hearts (n = 3 in each group).



View larger version (57K):
[in this window]
[in a new window]
  		Fig. 3. A: Western blot of CAMs from control, cocaine-treated (30 mg·kg–1·day–1, 2 wk), epinephrine-treated (3 mg/kg, 6 h), cocaine plus propranolol-treated (3 mg·kg–1·day–1, 2 wk), epinephrine plus propranolol-treated (3 mg/kg, 6 h), and propranolol only-treated mouse hearts (n = 6 in each group). Antibodies against ICAM-1, VCAM-1, and E- and L-selectins were used to determine relative protein expression. B: quantitative analysis of protein expression. Each protein's intensity was normalized to the relative intensity of GAPDH. CAM protein expression was significantly increased in cocaine-treated and epinephrine-treated mouse hearts compared with control hearts. Propranolol administration significantly attenuated both cocaine- and epinephrine-induced CAM expression. *P < 0.05 compared with control mouse hearts.

 
Immunohistochemistry revealed a significant increase in ICAM-1, VCAM-1, E-selectin, and L-selectin expression in cocaine-treated and epinephrine-treated hearts compared with control hearts (Fig. 4) but not in propranolol only-treated hearts (not shown). For ICAM-1, the percentage of the area with positively stained cells in cocaine-treated and epinephrine-treated hearts was 3.2 ± 0.7% and 1.9 ± 0.4% compared with control (1.2 ± 0.3%); for VCAM-1, the percentage of the area with positively stained cells in cocaine-treated and epinephrine-treated hearts was 3.0 ± 0.8% and 2.6 ± 0.8% compared with control (1.5 ± 0.4%); for E-selectin, the percentage of the area with positively stained cells in cocaine-treated and epinephrine-treated hearts was 4.5 ± 0.9% and 4.0 ± 0.8% compared with control (1.3 ± 0.4%); and for L-selectin, the percentage of the area with positively stained cells in cocaine-treated and epinephrine-treated hearts was 5.4 ± 1.1% and 2.7 ± 0.7% compared with control (0.5 ± 0.3%). The P value was <0.05 in all comparisons of cocaine- and epinephrine-treated hearts to saline-treated control hearts (n = 6 in each group). Immunohistochemistry analyses confirmed our Western blot findings. Heart sections containing ICAM, VCAM, and E-selectin were paraffin embedded; those containing L-selectin were frozen sections.



View larger version (151K):
[in this window]
[in a new window]
  		Fig. 4. Immunohistochemistry was performed to determine CAMs using antibodies against ICAM-1, VCAM-1, E-selectin, and L-selectin in slices of control, cocaine-treated (30 mg·kg–1·day–1, 2 wk), epinephrine-treated (3 mg/kg, 6 h), and propranolol only-treated (3 mg/kg, 6 h) mouse hearts (n = 6 in each group). ICAM-1, VCAM-1, E-selectin (paraffin-fixed slices), and L-selectin (frozen slices) increased significantly in cocaine- and epinephrine-treated hearts but not in propranolol only-treated hearts. Dark brown staining (arrows) indicates antibody-positive CAMs.

 
Propranolol attenuates cocaine- and epinephrine-induced PMN adhesion to the coronary endothelium. Figure 5 shows human PMN adhesion to the coronary endothelium. In cocaine-treated hearts 45 ± 5% of the infused human PMN and in epinephrine-treated hearts 38 ± 8% remained adhered to the coronary endothelium compared with 21 ± 4% in control hearts (P < 0.05 for both). The {beta}-adrenergic receptor blocker propranolol, however, significantly attenuated PMN adhesion to 29 ± 4% in cocaine-treated hearts (P < 0.05) and to 26 ± 5% in epinephrine-treated hearts (P < 0.05). Propranolol alone did not affect PMN adhesion.



View larger version (23K):
[in this window]
[in a new window]
  		Fig. 5. Human polymorphonuclear neutrophil (PMN) adhesion to the coronary endothelium. Human PMNs were diluted in modified Krebs solution, and 1 ml of the solution was infused into the coronary system. In cocaine-treated hearts, 45 ± 5% of the infused human PMNs remained adhered to the coronary endothelium compared with 21 ± 4% in control hearts (P < 0.05). PMN adhesion significantly increased to 38 ± 8% in epinephrine-treated hearts. The {beta}-adrenergic receptor blocker propranolol, however, significantly attenuated PMN adhesion to 29 ± 4% in cocaine-treated hearts and to 26 ± 5% in epinephrine-treated hearts. *P < 0.05 vs. control; **P < 0.05 vs. cocaine-treated hearts; ***P < 0.05 vs. epinephrine-treated hearts; n = 6 in each group.

 
CAM antibodies attenuate epinephrine-induced PMN adhesion to the coronary endothelium. To test whether CAMs affect PMN adhesion to the coronary endothelium, six epinephrine-treated hearts were perfused with a blocking antibody against either ICAM-1, VCAM-1, E-selectin, or L-selectin followed by infusion of PMN (Fig. 6). In epinephrine-treated hearts, PMN adhesion was significantly attenuated by antibodies against ICAM-1 (29 ± 4%), E-selectin (27 ± 2%), and L-selectin (25 ± 3%) compared with epinephrine-treated control hearts (43 ± 4%). The antibody against VCAM-1 had no significant effect on PMN adhesion (39 ± 2%). Combined antibodies against ICAM-1, E-selectin, and L-selectin significantly reduced PMN adhesion (15 ± 3%) (n = 6 in each group). The nonbinding, isotype-matched antibodies did not affect PMN adhesion to the coronary endothelium in epinephrine-treated hearts.



View larger version (17K):
[in this window]
[in a new window]
  		Fig. 6. Effects of antibodies against CAMs on PMN adhesion to the coronary endothelium in epinephrine-treated hearts. Epinephrine-treated hearts were perfused with blocking antibodies (5 µg/ml) against ICAM-1, VCAM-1, and E-selectin followed by infusion of 1 ml of PMNs. In epinephrine-treated hearts, PMN adhesion was significantly attenuated by antibodies against ICAM-1 (29% ± 4%), E-selectin (27 ± 2%), and L-selectin (25 ± 3%) compared with epinephrine-treated control hearts (43 ± 4%). The antibody against VCAM-1 had no significant effect on PMN adhesion (39 ± 2%). Combined antibodies against ICAM-1, E-selectin, and L-selectin significantly reduced PMN adhesion (15 ± 3%). The nonbinding, isotype-matched antibodies did not affect PMN adhesion to the coronary endothelium in epinephrine-treated hearts. *P <0.05 vs. epinephrine-treated control hearts; n = 6 in each group.

 
JNK and ERK inhibitors attenuate PMN retention. Figure 7A shows positive staining of phosphorylated JNK and ERK (but not of phosphorylated p38, not shown) of adhered PMN in cocaine- and epinephrine-treated hearts. JNK and ERK inhibitors SP-600125 and PD-98059 significantly attenuated PMN adhesion in cocaine-treated hearts from 45 ± 5% to 33 ± 3% for SP-600125 and to 29 ± 3% for PD-98059 and in epinephrine-treated hearts from 42 ± 5% to 31 ± 2% for SP-600125 and to 29 ± 2% for PD-98059. The combination of SP-600125 and PD-98059 further attenuated PMN adhesion to 25 ± 2% in cocaine-treated hearts and to 27 ± 3% in epinephrine-treated hearts (Fig. 7B).



View larger version (81K):
[in this window]
[in a new window]
  		Fig. 7. A: activation of JNK and ERK of PMNs. Phosphorylation of JNK, ERK, and p38 MAPK was analyzed to determine whether MAPK pathways of PMNs were involved in cocaine- and epinephrine-treated hearts. Heart slices from control, cocaine-treated, and epinephrine-treated hearts were stained with antibodies against phosphorylated JNK, ERK, and p38 MAPK. Dark brown staining indicates phosphorylated JNK- or ERK-positive cells. No phosphorylated p38 MAPK was found (not shown). B: role of JNK and ERK on PMN adhesion. JNK and ERK inhibitors SP-600125 (SP) and PD-98059 (PD) significantly attenuated PMN adhesion in cocaine- and epinephrine-treated hearts. Combined SP-600125 and PD-98059 further attenuated PMN adhesion in cocaine- and epinephrine-treated hearts. *P < 0.05 vs. cocaine-treated hearts; **P < 0.05 vs. epinephrine-treated hearts; n = 6 in each group.

 

   DISCUSSION
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
GRANTS
 REFERENCES
 
We have previously demonstrated that cocaine and catecholamines can exacerbate and propranolol can ameliorate viral myocarditis in mice, although the mechanisms remain unclear (26, 31, 33). The most important findings of the present study are that, first, upregulation of CAMs in cocaine-treated mouse hearts may be a major mechanism responsible for cocaine's inflammatory effects on the heart; second, epinephrine, which is elevated in cocaine abusers (9), mirrored the effects of cocaine, suggesting that catecholamines may be mediators of cocaine's inflammatory effects on the heart; and third, {beta}-adrenergic blockade significantly attenuated the effects on neutrophil retention in cocaine- and epinephrine-treated hearts. Because {beta}-adrenergic blocking agents are widely used clinically in a variety of conditions, our results may be of significance for the development of preventative and therapeutic approaches in patients susceptible to the proinflammatory effects of cocaine and catecholamines.

We administered epinephrine for 6 h as an acute treatment because a previous study has shown that, after 6–18 h of cocaine administration, ICAM-1 expression peaked in brain microvascular endothelial cells; on the other hand, cocaine's effect on VCAM-1 was most pronounced early (at 4 h) and became less significant at later times (8). In a mouse model of ischemia, E-selectin expression peaked between 5 and 24 h in the intestinal microvasculature (23). In our experiments, CAM expression was detected in the heart after 6 h of epinephrine administration. Moreover, we did not detect TNF-{alpha} or IL-6, which stimulate ICAM-1 and VCAM-1 expression in endothelial cells (5) and which modulate E-selectin expression in a mouse model of intestinal ischemia and reperfusion that used blocking antibody against TNF-{alpha} (23). Therefore, we propose that CAM expression appears to be stimulated by epinephrine rather than cytokines under our experimental conditions.

We used gene array analysis to generate a global view of CAM expression. ICAM-1, VCAM-1, E-selectin, and L-selectin were significantly upregulated in the cocaine-treated heart compared with the control heart. The upregulation of individual CAMs at the genetic level was further shown by RT-PCR for RNA (Fig. 2), Western blotting, and immunohistochemical staining for proteins (Figs. 3 and 4). Therefore, the gene array data provided consistent information for our cell adhesion studies.

Previous studies of cocaine and catecholamine action on the immune response showed that epinephrine upregulates monocyte L-selectin via a {beta}-adrenergic receptor-mediated effect (21). However, Kugelmass et al. (13) showed that intravenous cocaine but not norepinephrine activated circulating platelets through cocaine metabolites rather than an effect of the cocaine molecule itself. In the present study, propranolol significantly attenuated the upregulation of CAM mRNA and protein in cocaine- and epinephrine-treated hearts (Figs. 2–4). This phenomenon confirmed our hypothesis that cocaine and epinephrine upregulate CAM expression by increasing serum catecholamine levels, which subsequently stimulate {beta}-adrenergic receptors.

One important objective of the present study was to investigate cocaine's inflammatory mechanism by evaluation of PMN adhesion in isolated perfused mouse hearts. Kupatt et al. (14) tested the coronary neutrophil adhesion in guinea pig hearts using human PMN perfusion because PMN are difficult to obtain in mice. Therefore, we also used human PMN. In the present study, PMN adhesion to the coronary endothelium was 21 ± 4% in control hearts, which is similar to what Kupatt et al. (14) reported in guinea pigs (~18%). Cocaine administration significantly enhanced PMN adhesion to 45 ± 5%, whereas epinephrine mirrored the effects of cocaine by enhancing PMN adhesion to 38 ± 8%. Both cocaine and epinephrine affect PMN adhesion through {beta}-adrenergic stimulation. This is supported by our results that show that propranolol significantly attenuated the effects of cocaine and epinephrine of neutrophil adhesion to the coronary endothelium (Fig. 5). Our results are consistent with the findings of Gan et al. (8) that {beta}-adrenergic stimulation enhanced brain endothelial cell adhesion and migration.

CAMs are crucial molecules associated with neutrophil-endothelial adhesion at inflammatory sites (22, 30). Our results indicate that ICAM-1, E-selectin, and L-selectin contributed to PMN adhesion, which is supported by our findings that the respective antibodies attenuated PMN adhesion to the coronary endothelium in epinephrine-treated hearts (Fig. 6). Our findings are in agreement with those of Simon et al. (25), who reported that ICAM-1 increased inflammatory cell sequestration, and Jones et al. (12), who reported that ICAM-1 and E-selectin are involved in leukocyte adhesion in the pathogenesis of infarcted mouse hearts. The antibody against VCAM-1, however, had little effect on PMN adhesion (Fig. 6), which is similar to the findings of Gan et al. (8) who reported that VCAM-1 has less effect on neutrophil adhesion in brain microvascular endothelial cells. Our results indicate that upregulation of ICAM-1 and selectins plays an important role in epinephrine-induced neutrophil homing.

The family of MAPKs are important in cellular responses to inflammation. Simon et al. (25) reported that the JNK/ERK pathway is involved in ligation and clustering of L-selectin and results in increased ICAM-1 adhesiveness through de novo expression of active integrin and increased inflammatory cell sequestration and emigration of neutrophils. We also observed that the JNK and ERK signaling pathway is activated in cocaine- and epinephrine-treated hearts (Fig. 7A), where neutrophil adhesion was significantly increased (Fig. 5). The central importance of JNK or ERK is further supported by the response to their respective inhibitors, SP-600125 or PD-98059, which were administered before PMN infusion and which blocked the activation of their signaling pathway (Fig. 7B).

Oxidative stress may also play an important role in CAM expression following cocaine administration. Moritz et al. (17) reported an increase in oxidative stress in rat myocardium after 2 days of cocaine administration; stress was indicated by an increase in lipid peroxidation and antioxidant enzymes. In a transgenic rat model, characterized by hypertension and cardiac injury, stimulation of oxidative stress was followed by activation of the transcription factor NF-{kappa}B, resulting in expression of adhesion molecules (ICAM-1 and VCAM-1), leukocyte infiltration in the vascular wall, and inflammation (15). Conceivably, then, cocaine-induced oxidative stress may also contribute to the increased expression of endothelial CAMs.

It is well known that epinephrine is one of the most important catecholamines elevated in cocaine-treated animals (9, 18, 19). Our data show that epinephrine mirrors cocaine's effect on CAM regulation and PMN adhesion to the coronary endothelium. We propose that the effects of cocaine on CAM expression may occur at least partially through elevated epinephrine levels in mice. However, we did not directly measure serum epinephrine levels in cocaine-treated mice. Further studies are needed to investigate whether there is a dose-response correlation between cocaine vs. CAM expression and epinephrine vs. CAM expression, which may have clinical relevance for preventative and therapeutic applications. Because epinephrine is both an {alpha}- and {beta}-adrenoceptor agonist, propranolol was administered to cocaine- and epinephrine-treated mice to determine whether the effect of epinephrine on CAM expression was mediated by {beta}-adrenoceptors. Our results revealed that propranolol significantly attenuated PMN adherence to coronary endothelium via CAM regulation. However, we did not determine whether {beta}1- or {beta}2-receptors mediated the effect since propranolol blocks both receptors.

It has been shown that cytokines stimulate CAM expression both in vivo and in vitro (5, 23). Because TNF-{alpha} was significantly increased in mouse hearts and serum after long-term treatment with cocaine (31–33), we conclude that cocaine's effects on CAM expression might also occur through elevated cytokine levels. Our results may explain the findings of Gan et al. (8) showing that cocaine in a concentration (10–5 M) detected in the plasma of cocaine addicts has effects on monocyte and neutrophil adhesion comparable to that of TNF-{alpha} (50 ng/ml). In the present study, however, TNF-{alpha} and IL-6 levels were not detectable in epinephrine-treated hearts. We conclude that CAM expression appears to be stimulated by epinephrine rather than by cytokines such as TNF-{alpha} and IL-6 under our experimental conditions.

The present study demonstrates that {beta}-adrenergic blockade substantially attenuates the effects of cocaine and epinephrine on PMN adherence to the coronary endothelium by upregulation of CAM expression. Our results support the stimulatory role of catecholamines on CAM expression and suggest that moderate doses of propranolol may be clinically useful to ameliorate inflammation in patients with myocarditis of viral causation as a preventative and therapeutic measure.


   GRANTS
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
REFERENCES
 
This study was supported by National Institute on Drug Abuse Grants DA-11762 and DA-12774 (to J. P. Morgan). I. Amende was supported by Förderkreis zur Verbesserung des Gesundheitswesens e.V.


   ACKNOWLEDGMENTS
 
We especially thank Dr. Ionita C. Ghiran, Allergy Division, Beth Israel Deaconess Medical Center, for help in the human PMN isolation.


   FOOTNOTES
 

Address for reprint requests and other correspondence: J. P. Morgan, Beth Israel Deaconess Medical Center, Harvard Medical School, RW453, 330 Brookline Ave., Boston, MA 02215 (E-mail: jmorgan{at}caregroup.harvard.edu)

The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

* Y. Chen and Q. Ke contributed equally to this work. Back


   REFERENCES
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
 REFERENCES
 

  1. Braun M, Pietsch P, Zepp A, Schror K, Baumann G, and Felix SB. Regulation of tumor necrosis factor-{alpha}- and interleukin-1-{beta}-induced induced adhesion molecule expression in human vascular smooth muscle cells by cAMP. Arterioscler Thromb Vasc Biol 17: 2568–2575, 1997.[Abstract/Free Full Text]
  2. Buemi M, Allegra A, Aloisi C, Corica F, Alonci A, Ruello A, Montalto G, and Frisina N. Cold pressor test raises serum concentrations of ICAM-1, VCAM-1, and E-selectin in normotensive and hypertensive patients. Hypertension 30: 845–847, 1997.[Abstract/Free Full Text]
  3. Cho T, Tanimura A, and Saito Y. Catecholamine-induced cardiopathy accompanied with pheochromocytoma. Acta Pathol Jpn 37: 123–132, 1987.[Medline]
  4. Cotran R. Acute and chronic inflammation. In: Pathologic Basis of Disease, edited by Cotran VKR and Collins T. Philadelphia, PA: Saunders, 1999, p. 50–88.
  5. Daxecker H, Raab M, Markovic S, Karimi A, Griesmacher A, and Mueller MM. Endothelial adhesion molecule expression in an in vitro model of inflammation. Clin Chim Acta 325: 171–175, 2002.[Medline]
  6. Deisher TA, Garcia I, and Harlan JM. Cytokine-induced adhesion molecule expression on human umbilical vein endothelial cells is not regulated by cyclic adenosine monophosphate accumulation. Life Sci 53: 365–370, 1993.[CrossRef][ISI][Medline]
  7. Galea P, Thibault G, Lacord M, Bardos P, and Lebranchu Y. IL-4, but not tumor necrosis factor-alpha, increases endothelial cell adhesiveness for lymphocytes by activating a cAMP-dependent pathway. J Immunol 15: 588–596, 1993.
  8. Gan X, Zhang L, Berger O, Stins MF, Way D, Taub DD, Chang SL, Kim KS, House SD, Weinand M, Witte M, Graves MC, and Fiala M. Cocaine enhances brain endothelial adhesion molecules and leukocyte migration. Clin Immunol 91: 68–76, 1999.[CrossRef][ISI][Medline]
  9. Haft JI. Cardiovascular injury induced by sympathetic catecholamines. Prog Cardiovasc Dis 17: 73–86, 1974.[CrossRef][ISI][Medline]
  10. Hampton TG, Amende I, Travers KE, and Morgan JP. Intracellular calcium dynamics in mouse model of myocardial stunning. Am J Physiol Heart Circ Physiol 274: H1821–H1827, 1998.[Abstract/Free Full Text]
  11. Jentzen JM. Cocaine-induced myocarditis. Am Heart J 11: 1398–1399, 1989.
  12. Jones SP, Trocha SD, Strange MB, Granger DN, Kevil CG, Bullard DC, and Lefer DJ. Leukocyte and endothelial cell adhesion molecules in a chronic murine model of myocardial reperfusion injury. Am J Physiol Heart Circ Physiol 279: H2196–H2220, 2000.[Abstract/Free Full Text]
  13. Kugelmass AD, Shannon RP, Yeo EL, and Ware JA. Intravenous cocaine induces platelet activation in the conscious dog. Circulation 91: 1336–1340, 1995.[Abstract/Free Full Text]
  14. Kupatt C, Habazettl H, Zahler S, Weber C, Becker BF, Messmer K, and Gerlach E. ACE-inhibition prevents postischemic coronary leukocyte adhesion and leukocyte-dependent reperfusion injury. Cardiovasc Res 36: 386–395, 1997.[Abstract/Free Full Text]
  15. Luft FC, Mervaala E, Mueller DN, Gross V, Schmidt F, Park JK, Schmitz C, Lippoldt A, Breu V, Dechend R, Dragun D, Schneider W, Ganten D, and Haller H. Hypertension-induced end-organ damage: a new transgenic approach to an old problem. Hypertension 33: 212–218, 1999.[Abstract/Free Full Text]
  16. Luscinskas FW, Brock AF, Arnaout MA, and Gimbrone MA Jr. Endothelial-leukocyte adhesion molecule-1-dependent and leukocyte (CD11/CD18)-dependent mechanisms contribute to polymorphonuclear leukocyte adhesion to cytokine-activated human vascular endothelium. J Immunol 142: 2257–2263, 1989.[Abstract]
  17. Moritz F, Monteil C, Isabelle M, Bauer F, Renet S, Mulder P, Richard V, and Thuillez C. Role of reactive oxygen species in cocaine-induced cardiac dysfunction. Cardiovasc Res 59: 834–843, 2003.[Abstract/Free Full Text]
  18. Nash CB and Carter JR. Hemorrhagic myocarditis and cardiovascular collapse induced by catecholamine infusion. Arch Int Pharmacodyn Ther 166: 172–180, 1967.[Medline]
  19. Om A. Cardiovascular complications of cocaine. Am J Med Sci 303: 333–339, 1992.[ISI][Medline]
  20. Pober JS, Slowik MR, De Luca LG, and Ritchie AJ. Elevated cyclic AMP inhibits endothelial cell synthesis and expression of TNF-induced endothelial leukocyte adhesion molecule-1, and vascular cell adhesion molecule-1, but not intercellular adhesion molecule-1. J Immunol 150: 5114–5123, 1993.[Abstract]
  21. Rainer TH, Lam N, and Cocks RA. Adrenaline upregulates monocyte L-selectin in vitro. Resuscitation 43: 47–55, 1999.[CrossRef][ISI][Medline]
  22. Rosen S. Selectins. In: Guide to the Extracellular Matrix and Adhesion Proteins, edited by Vale KTR. New York: Oxford Univ. Press, 1999, p. 290–297.
  23. Russell J, Epstein CJ, Grisham MB, Alexander JS, Yeh KY, and Granger DN. Regulation of E-selectin expression in postischemic intestinal microvasculature. Am J Physiol Gastrointest Liver Physiol 278: G878–G885, 2000.[Abstract/Free Full Text]
  24. Shephard RJ. Adhesion molecules, catecholamines and leukocyte redistribution during and following exercise. Sports Med 33: 261–284, 2003.[CrossRef][ISI][Medline]
  25. Simon SI, Cherapanov V, Nadra I, Waddell TK, Seo SM, Wang Q, Doerschuk CM, and Downey GP. Signaling functions of L-selectin in neutrophils: alterations in the cytoskeleton and colocalization with CD18. J Immunol 163: 2891–2901, 1999.[Abstract/Free Full Text]
  26. Soodini G and Morgan JP. Can cocaine abuse exacerbate the cardiac toxicity of human immunodeficiency virus? Clin Cardiol 24: 177–181, 2001.[Medline]
  27. Toyozaki T, Saito T, Takano H, Yorimitsu K, Kobayashi S, Ichikawa H, Takeda K, and Inagaki Y. Expression of intercellular adhesion molecule-1 on cardiac myocytes for myocarditis before and during immunosuppressive therapy. Am J Cardiol 72: 441–444, 1993.[Medline]
  28. Tyagi S, Nicholson-Weller A, Barbashov SF, Tas SW, and Klickstein LB. Intercellular adhesion molecule 1 and {beta}2 integrins in C1q-stimulated superoxide production by human neutrophils: an example of a general regulatory mechanism governing acute inflammation. Arthritis Rheum 43: 2248–2259, 2000.[CrossRef][Medline]
  29. Van Vliet PD, Burchell HB, and Titus JL. Focal myocarditis associated with pheochromocytoma. N Engl J Med 274: 1102–1108, 1966.[ISI][Medline]
  30. Vestweber D and Blanks JE. Mechanisms that regulate the function of the selectins and their ligands. Physiol Rev 79: 181–213, 1999.[Abstract/Free Full Text]
  31. Wang Y, Huang DS, and Watson RR. In vivo and in vitro cocaine modulation on production of cytokines in C57BL/6 mice. Life Sci 54: 401–411, 1994.[CrossRef][Medline]
  32. Wang JF, Yang Y, Sullivan MF, Min J, Cai J, Zeldin DC, Xiao YF, and Morgan JP. Induction of cardiac cytochrome p450 in cocaine-treated mice. Exp Biol Med 227: 182–188, 2002.[Abstract/Free Full Text]
  33. Wang JF, Zhang J, Min JY, Sullivan MF, Crumpacker CS, Abelmann WH, and Morgan JP. Cocaine enhances myocarditis induced by encephalomyocarditis virus in murine model. Am J Physiol Heart Circ Physiol 282: H956–H963, 2002.[Abstract/Free Full Text]



This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
G. Monchanin, L. D. Serpero, P. Connes, J. Tripette, D. Wouassi, L. Bezin, A. Francina, J. Ngongang, M. de la Pena, R. Massarelli, et al.
Effects of progressive and maximal exercise on plasma levels of adhesion molecules in athletes with sickle cell trait with or without {alpha}-thalassemia
J Appl Physiol, January 1, 2007; 102(1): 169 - 173.
[Abstract] [Full Text] [PDF]

Home page
 Mayo Clin. Proc.Home page
S. Arora, F. Alfayoumi, and V. Srinivasan
Transient Left Ventricular Apical Ballooning After Cocaine Use: Is Catecholamine Cardiotoxicity the Pathologic Link?
Mayo Clin. Proc., June 1, 2006; 81(6): 829 - 832.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
288/5/H2323    most recent
00822.2004v1
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 ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (5)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chen, Y.
Right arrow Articles by Morgan, J. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chen, Y.
Right arrow Articles by Morgan, J. P.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2005 by the American Physiological Society.