| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Internal Medicine-1, National Defense Medical College, Saitama, Japan
Submitted 18 March 2005 ; accepted in final form 30 January 2006
 |
ABSTRACT |
|---|
 TOP ABSTRACT METHODSRESULTSDISCUSSIONREFERENCES |
|---|
. We then analyzed their heart morphology and functions. Histological and echocardiographic analyses revealed concentric LV hypertrophy with preserved LV systolic function in the mice. Our results suggest that myocardial expression of IL-1 is sufficient to cause LV hypertrophy.
myocardium; left ventricular systolic function; cardiovascular disease
We previously reported that mice with a ubiquitous overexpression of human IL-1 (hIL-1), which were originally generated as a mouse model of rheumatoid arthritis, unexpectedly showed prominent left ventricular (LV) hypertrophy (7). The study did not, however, define whether the specific expression of IL-1 in the myocardium caused the LV hypertrophy, because the systemic expressions might induce the LV hypertrophy. Therefore, to elucidate the role of myocardial expression of IL-1 in the myocardium, we developed transgenic (Tg) mice with a constitutive overexpression of hIL-1 restricted to cardiomyocytes under the control of -myosin heavy chain (MHC) promoter.
The Tg mice exhibited concentric LV hypertrophy with a preserved LV systolic function. Our data suggest that cardiac expression of IL-1 thus is sufficient to cause LV hypertrophy.
|
METHODS |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
cDNA (Immunex) was derived from a plasmid of the chicken 
-actin promoter containing cytomegalovirus enhancer-hIL-1. The plasmid had been used for generation of mice with a ubiquitous overexpression of hIL-1 (17). The fragment containing hIL-1 cDNA was excised by Bgl II/Xba I (770 bp). The terminal fragment was blunted by the Klenow fragment (Takara Bio). The plasmid containing the -MHC promoter construct (pGL--MHC-SVpA) (11) was kindly donated by Dr. Arthur M. Feldman. The fragment containing hIL-1 cDNA was inserted into the plasmid that was digested by Hind III. Finally, we generated the Tg construct pGL--MHC-hIL-1-SVpA (9.88 kbp). BamH I digestion produced a linear 6.96-kbp fragment used for microinjection into mouse embryos (Fig. 1).
|
Generation and identification of Tg mice. C57BL/6N mice were used for the generation of Tg mice. The Tg mice were identified by PCR with primers as follows: 5'-CAC ATA GAA GCC TAG CCC AC-3' (forward) and 5'-TTC CAC CAC TGC TCC CAT TC-3' (reverse). The PCR conditions were as follows: 30 cycles of denaturation at 95°C for 10 s, annealing at 62°C for 15 s, and extension at 72°C for 90 s.
Quantitative PCR was performed to estimate the DNA copy number of transgene loci in each line. The primers specific for hIL-1 and an internal normalizer gene, RNase P1, were used in multiplex PCR on a PCR thermocycler (TaqMan 7700, Applied Biosystems, Foster City, CA) following the manufacturer's recommended conditions. The following primers were used: hIL-1 [5'-TGT ATG TGA CTG CCC AAG ATG AA-3' (forward) and 5'-CCT GTG ATG GTT TTG GGT ATC TC-3' (reverse)] and RNase P1 [5'-CAC TTA CTG GTC TGT GAG AAA TCC A-3' (forward) and 5'-TGC GTC TCC ACG AGA TGC T-3' (reverse)]. The data are shown as the change in cycle threshold (
Ct), which can be converted to the relative transgene DNA copy number as follows: 2
.
Northern blot analysis.
Total RNA was purified from quick-frozen cardiac tissue specimens from 12-wk-old male mice using the RNeasy protocol (Qiagen). Total RNA (5–10 µg) was electrophoresed in 1.2% agarose-formaldehyde gel, blotted onto nylon membranes (Roche Molecular Biochemicals), and UV cross-linked. Hybridization was performed overnight at 42°C using a digoxigenin-labeled probe generated with a digoxigenin DNA labeling kit (Roche Molecular Biochemicals). The probe was a 660-bp Hind III/Hinc II fragment from hIL-1 cDNA (Immunex). For visualization of digoxigenin-labeled IL-1 cDNA, the membranes were washed and incubated with alkaline phosphatase-labeled anti-digoxigenin Fab fragments and then in a solution of alkaline phosphatase substrate (4-nitro blue tetrazolium chloride and bromo-4-chloro-3-indolyl phosphate). The hybridization signals were detected using a scanner (Epson). The mRNA levels were qualified by 28S and 18S ribosomal RNA ethidium bromide staining.
Determination of cytokine levels.
The myocardial cytokine levels were determined using a specific ELISA of hIL-1 (Japan Immunoresearch Laboratories), mouse IL-1 (Biosource International), mouse IL-1 and mouse TNF- (Endogen), and mouse IL-6 (R & D Systems). At 12 wk of age, male mice were killed with an overdose of pentobarbital sodium (200 mg/kg ip), and the hearts were removed and homogenized in ice-cold tissue protein-extraction reagent (T-PER, Pierce Biotechnology) with protease inhibitors (Sigma-Aldrich). The homogenized solutions were spun at 10,000 rpm for 20 min at 4°C. The supernatants for the total protein level of 100 µg/ml were applied to the ELISA plate. The serum levels of hIL-1 were also analyzed using a specific ELISA.
Western blot analysis.
The protein samples were prepared from heart tissue specimens from 12-wk-old male mice. Ventricular tissue specimens were homogenized in ice-cold tissue protein-extraction reagent containing protease inhibitors (Sigma-Aldrich). The extracts of 50 µg of protein were separated by SDS-PAGE, and the proteins were electrophoretically transferred to polyvinylidene difluoride filters. The filters were washed and incubated with primary antibody: rabbit polyclonal anti-nuclear factor (NF)-
B p65 antibody (Abcam), anti-phosphorylated p65 antibody (Ser536) and anti-phosphorylated p38 antibody (Cell Signaling Technology), and anti-p38 MAPK antibody (Santa Cruz Biotechnology). The filters were washed and then incubated with horseradish peroxidase-conjugated anti-rabbit secondary antibody (Amersham Pharmacia Biotech). The signals were visualized using the ECL Plus system (Amersham Pharmacia Biotech). Densitometry was done using an image analysis software (Scion Image, Scion) on a computer.
Histological analysis. At 12 wk of age the mice were killed with an overdose pentobarbital sodium (200 mg/kg ip). The hearts were removed and rinsed well in ice-cold normal saline and then fixed in 4% paraformaldehyde in PBS. The tissue blocks were embedded in paraffin for sectioning (7 µm). Tissue sections were stained with hematoxylin-eosin or Masson's trichrome. The regions in the left and right ventricular free wall were used for the analysis. The myocyte cross-sectional area was measured in the sections stained with Masson's trichrome as reported previously (5).
Myocardial ultrastructural analysis. An ultrastructural analysis of morphological changes in Tg mice at 12 wk of age was performed after the heart was fixed in conventional fixing solutions [4% (vol/vol) paraformaldehyde and 1% (vol/vol) glutaraldehyde in PBS]. All samples were processed after fixation and dehydration for embedding in epoxy resin. Next, ultrathin sections from a midportion of the LV free wall were stained with uranyl and lead acetate and then examined by transmission electron microscopy (TEM; Nihon Electric).
Echocardiography. At 12 wk of age, male mice were anesthetized intraperitoneally with a mixture of ketamine (100 mg/kg) and xylazine (2.5 mg/kg), and their chests were shaved. Next, transthoracic echocardiography was performed using a Hewlett-Packard Sonos 7500 ultrasound system equipped with a 15-MHz linear transducer (Philips). M-mode studies were analyzed as reported previously (7).
Measurement of blood pressure and heart rate. Arterial blood pressure and heart rate were measured in conscious mice by the tail cuff method.
Detection of gene expression.
Fetal gene expression was detected by purification of total RNA from cardiac ventricular tissue from 12-wk-old male mice with use of the RNeasy protocol (Qiagen). First-strand cDNA was synthesized using RT with random hexamers from 1 µg of total RNA in a 20-µl reaction volume according to the manufacturer's protocol (Perkin-Elmer); then one-tenth of the resulting RT product was applied to 25 µl of PCR solutions containing 1.5 mM Mg2+, 0.2 µM primers, 0.2 mM dNTPs, and 2.5 U/100 µl Taq DNA polymerase (Perkin-Elmer). PCR conditions for the various primers were as follows: 32 cycles of denaturation at 95°C for 15 s, annealing at 58°C for 15 s, and extension at 72°C for 60 s for atrial natriuretic factor [ANF, 5'-AAG AGG GCA GAT CTA TCG GA-3' (forward) and 5'-TTG GCT TCC AGG CCA TAA TTG-3' (reverse)]; 30 cycles of denaturation at 95°C for 15 s, annealing at 61°C for 15 s, and extension at 72°C for 60 s for B-type natriuretic peptide [BNP, 5'-CAG CTC TTG AAG GAC CAA GG-3' (forward) and 5'-AAG AGA CCC AGG CAG AGT CA-3' (reverse)]; 30 cycles of denaturation at 95°C for 15 s, annealing at 60°C for 15 s, and extension at 72°C for 60 s for -MHC [5'-AGA GGA GAA GGC CAA GAA GG-3' (forward) and 5'-GCA GCC GCA TTA AGT TCT TC-3' (reverse)]; 32 cycles of denaturation at 95°C for 15 s, annealing at 62°C for 15 s, and extension at 72°C for 60 s for -MHC [5'-cag ctc ttg aag gac caa gg-3' (forward) and 5'-aag aga ccc agg cag agt ca-3' (reverse)]; 30 cycles of denaturation at 95°C for 15 s, annealing at 61°C for 15 s, and extension at 72°C for 60 s for sarco/endoplasmic reticulum Ca2+-ATPase [SERCA2a, 5'-AAG CTAT GGG AGT GGT TGG TG-3' (forward) and 5'-ACA ACC AAG GGT CTC CAC AG-3' (reverse)]; 30 cycles of denaturation at 95°C for 15 s, annealing at 60°C for 15 s, and extension at 72°C for 60 s for ryanodine Ca2+-release channels [CRC, 5'-AGG TGG TGC CGT ATC AGT TC-3' (forward) and 5'-CAT CCA CAG CCT GGT AGG TT-3' (reverse)]; and 30 cycles of denaturation at 95°C for 30 s, annealing at 62°C for 15 s, and extension at 72°C for 120 s for GAPDH [5'-GGT CCA GGG TTT CTT ACT CC-3' (forward) and 5'-AAG CCC ATC ACC ATC TTC CA-3' (reverse)]. Densitometry was done using an image analysis software (Scion Image) on a computer. mRNA levels were corrected for the mRNA level of GAPDH and are expressed as percentage of non-Tg mice.
Gene expressions of adhesion molecules were detected using a quantitative PCR technique. RT was performed with TaqMan RT reagent (Applied Biosystems) with random oligonucleotide primers. The conditions were as follows: 25°C for 10 min, 48°C for 30 min, and 95°C for 5 min. TaqMan probes and primer sets for intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), platelet-endothelial cell adhesion molecule 1 (PECAM-1), and -actin mRNAs are commercially available and were purchased from Applied Biosystems. Amplification was performed with a sequence detection system (Prism 7700, Applied Biosystems) under the following conditions: 50°C for 2 min, 95°C for 10 min, and 40 cycles at 95°C for 15 s and 60°C for 1 min. PCR results were analyzed with Sequence Detector version 1.6 (Applied Biosystems). To correct for variations in the total RNA content and unequal RT efficiency, ICAM-1, VCAM-1, and PECAM-1 quantities were normalized to the amount of -actin mRNA.
Statistical analysis.
Values are means ± SE. Two-tailed Student's t-test and the 
2 test were used for statistical analysis. P < 0.05 was considered to be statistically significant.
|
RESULTS |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
Ct values were –4.2, –3.0, and –5.1 for Tg17, Tg50, and Tg71, respectively. Because the most prominent increase in heart weight-to-body weight ratio was observed in the Tg71 line, male mice of the Tg71 line were used in this study. The Tg mice show normal growth and normal gross appearance, and the 1-yr survival rate of the Tg mice is similar to that of the non-Tg mice (>95% for each group).
mRNA expressions of hIL-1.
A Northern blot analysis demonstrated a high level of hIL-1 mRNA in the ventricular tissue specimens of the Tg mice (Fig. 2A). Signals were either weak or absent in other organs, such as the lung and spleen (Fig. 2B).
|
levels of ventricular tissue specimens in Tg mice were 73 pg/100 µg protein, on average, as determined by a specific ELISA (n = 6 per group; Table 1). However, the serum level of hIL-1 was too low to be detected. There were no significant differences in mouse IL-1 (too low to be detected in both groups), IL-1 (7.6 ± 0.7 and 8.1 ± 0.7 pg/100 µg protein, respectively), and TNF- (1.1 ± 0.1 and 1.3 ± 0.1 pg/100 µg protein, respectively) in ventricular tissue specimens between the Tg and non-Tg mice (n = 6 per group; Table 1). The protein expression of IL-6, a downstream cytokine of IL-1, in the ventricular tissue samples was greater in Tg than in non-Tg mice (20.6 ± 8.2 vs. 2.0 ± 1.1 pg/100 µg protein, P < 0.05), suggesting that the Tg-derived hIL-1 was active as a proinflammatory cytokine in mice.
|
B (15). We thus examined the signal activations of p38 MAPK and p65 NF-B, which are important intracellular signaling molecules in inflammation, to estimate whether transgene-derived hIL-1 is biologically active as a proinflammatory cytokine in mice, because the transgene was of human origin. The ratio of phosphorylated p38 to p38 (Fig. 3A) and phosphorylated p65 to p65 (Fig. 3B) was significantly higher (P < 0.05) in Tg than in non-Tg mice (1,350 ± 13 vs. 148 ± 4%, n = 4 per group).
|
|
|
|
|
|
-MHC (536 ± 40%) gene expressions and a decrease in -MHC (66 ± 4%), SERCA2a (80 ± 2%), and CRC (88 ± 3%) gene expressions in the Tg mice compared with the non-Tg mice (n = 4 per group; Fig. 7).
|
-actin (4.73 ± 0.46 and 2.15 ± 0.32% for Tg and non-Tg, respectively, P < 0.05) and VCAM-1-to--actin (15.8 ± 2.0 and 8.3 ± 0.5% for Tg and non-Tg, respectively, P < 0.05) mRNA ratios were significantly elevated in the Tg myocardium compared with the non-Tg myocardium (n = 4 per group). In contrast, the PECAM-1-to--actin mRNA ratio (89.7 ± 3.9 and 88.8 ± 6.3% for Tg and non-Tg, respectively, P = NS) did not increase (n = 4 per group). |
DISCUSSION |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
.
An elevated expression of IL-1 in hearts has been revealed in a variety of cardiovascular diseases, such as myocarditis (22), myocardial ischemia and infarction (18), and congestive heart failure (13, 18, 22). IL-1 is also implicated in the pathogenesis of the hypertrophied myocardium in vitro and in vivo (21). We found that mice with a ubiquitous overexpression of hIL-1, which were originally generated as a mouse model of rheumatoid arthritis, unexpectedly showed prominent LV hypertrophy and congestive heart failure to death within 2 wk after birth. However, the findings we reported did not address whether hIL-1 expressed in the myocardium caused the LV remodeling, because hIL-1 was ubiquitously expressed in the Tg mice. Thus we generated and analyzed Tg mice with a cardiac-specific overexpression of hIL-1 in this study. The Tg mice showed an increased heart weight-to-body weight ratio. A histological analysis revealed that the hypertrophy was the result of the increased size of the myocardium. TEM observations revealed rounded mitochondria that were increased in number. The overexpression of hIL-1 increased mRNA expressions of ANF, BNP, and -MHC and decreased mRNA expressions of -MHC, SERCA2a, and CRC in the myocardium. An echocardiographic study revealed that the end-diastolic LV wall was thicker in the Tg than in the non-Tg mice. These findings are compatible with LV hypertrophy (9). The responses in the Tg heart are further evidence that LV hypertrophy is the result of hIL-1 overexpression, because hypertrophy was observed without evidence of hemodynamic overload.
Cardiac hypertrophy is defined as an enlargement of the heart associated with an increase in cardiomyocyte cell volume that occurs in response to diverse pathophysiological stimuli such as hypertension, ischemic heart disease, valvular insufficiency, infectious agents, or mutations in sarcomeric genes (14). Hypertrophic growth of the myocardium is thought to preserve pump function, although prolongation of the hypertrophic state is a leading predictor for the development of sudden death and heart failure (6, 12). In our study, the cardiac-specific hIL-1-overexpressing mice showed LV hypertrophy but a preserved systolic function and a normal 1-yr survival rate. However, we revealed that the pathological significance of the LV hypertrophy observed in this study was an increase in ANF, BNP, and -MHC gene expression and a decrease in -MHC, SERCA2a, and CRC gene expression in the myocardium. Therefore, these results suggest that the hypertrophy may be a consequence of compensatory mechanisms. The result is different from those observed in the ubiquitous hIL-1-overexpressing mice, which demonstrated congestive heart failure to death within 2 wk after birth (7). We speculate that the phenotypic difference most likely is due to the different regulation of the hIL-1 expression by each promoter as well as the distinct degrees of hIL-1 expression. The gene expression controlled under the -MHC promoter can affect the myocardium only after birth, whereas the expression under the CAG promoter can affect the myocardium even before birth (20). The IL-1 transgene regulated under the CAG promoter acts on fetal myocardial cells, which maintain the capacity to divide. On the other hand, the IL-1 transgene under the -MHC promoter acts on mature myocardial cells, which have no capacity to divide. This could lead to an increase in myocyte number and volume and cause severe ventricular hypertrophy and congestive heart failure in CAG-IL-1 Tg mice. In addition, because of a ubiquitous overexpression of IL-1 in CAG-IL-1 Tg mice, mononuclear cells and macrophages overexpressing IL-1 appeared to gain a tissue-destructive phenotype (17), which was likely to cause robust inflammatory infiltrations in the hearts and, subsequently, an aggravation of myocardial injury.
The effects of TNF-, which is also a proinflammatory cytokine, on the myocardium have been well investigated. A recent report demonstrated that a chronic overexpression of TNF- (TNF- Tg) in mice induced LV hypertrophy, eventual LV dilation, and congestive heart failure (8). In contrast, in our mice, a persistent overexpression of IL-1 in the heart induced ventricular hypertrophy, but not ventricular dilatation or congestive heart failure. These phenotypic differences might be explained by the cytokines expressed in the heart. The TNF- Tg mice showed a significant increase in the myocardial TNF- and IL-1 levels (8). Kadokami et al. (8) reported that, in TNF- Tg mice treated with a TNF--neutralizing antibody, LV systolic function was improved to the same level as in the non-Tg mice; however, these TNF- Tg mice still showed a high expression of myocardial IL-1 without any attenuation of development of LV hypertrophy. In our study, IL-1 Tg mice showed a significant increase in the myocardial level of hIL-1, but not TNF- (7).
There has also been considerable interest in the relative roles of IL-1 and IL-1 in cardiac hypertrophy. Both isoforms have been demonstrated to be involved in cardiac hypertrophy (1, 10), and mRNA expressions of IL-1 in hypertrophied myocardium were reported to be higher than those of IL-1 (1, 10). Although the relative pathogenic contributions of IL-1 and IL-1 to myocardial hypertrophy remain to be fully elucidated, the roles of IL-1 in cardiac hypertrophy have been well investigated. The expression of IL-1 increased in hypertrophied hearts with pressure overload in vivo (21) and in hypertrophied myocardium in vitro (13). In addition, in vitro experiments have revealed that IL-1 can induce cardiomyocyte hypertrophy (19, 23). The two isoforms bind to the same receptor, IL-1 type 1 receptor, to elicit the biological effects of IL-1 (4). However, the precursor form of IL-1, in contrast to IL-1, is known to act as a membrane-associated IL-1 (4). We could not detect hIL-1 protein in the serum, suggesting that membrane-associated IL-1 on the cardiomyocytes contributes to cardiac hypertrophy through cell-to-cell interaction. Furthermore, by histological evaluation, we recognized a lack of inflammatory infiltrates in the Tg myocardium. Thus we measured the mRNA expressions of cell adhesion molecules. ICAM-1 and VCAM-1 were found to induce the firm adhesion of inflammatory cells on the vascular surface, whereas PECAM-1 plays a critical role in the extravasation of leukocytes into underlying tissue as previously reported (2). In our study, we demonstrated an increase in ICAM-1 and VACM-1, but not PECAM-1, gene expression in the Tg myocardium. The chronic cardiac-specific overexpression of IL-1 did not augment PECAM expression in the myocardium, which might result in a lack of leukocyte extravasation into the myocardial tissue.
Niki et al. (17) reported that the bone marrow macrophages derived from hIL-1-overexpressing mice stimulated proliferation of murine cells and that the mitogenic activity was suppressed by the neutralizing antibody against hIL-1. In our study, to confirm the transactivation of murine myocardium by hIL-1, we demonstrated an increase in IL-6 protein levels, phosphorylated p38 MAPK, and phosphorylated p65 (Ser536) NF-B in the Tg hearts. IL-6, a downstream cytokine activated by IL-1, was reported to be a cardioprotective and hypertrophic signal via gp130. Thus gp130 signals as an effector might be involved in the pathogenesis of the phenotypes observed in this study. Both p38 MAPK and NF-B have been traditionally implicated as pivotal intracellular mediators of the inflammatory responses induced by IL-1. p38 MAPK is also associated with myocardial hypertrophy. However, it remains to be fully elucidated whether p38 MAPK itself plays a role in the onset and development of myocardial hypertrophy in mammalian adult hearts (3, 16, 24).
In summary, we generated mice with a cardiac-specific overexpression of hIL-1. The Tg mice showed concentric LV hypertrophy with a preserved LV systolic function. Our findings suggest that the cardiac expression of IL-1 may, therefore, cause LV hypertrophy in vivo.
|
FOOTNOTES |
|---|
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.
|
REFERENCES |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
. J Card Fail 7: 355–364, 2001.[CrossRef][Web of Science][Medline] antibody limits heart failure in a transgenic model. Circulation 104: 1094–1097, 2001.. Circ Res 81: 627–635, 1997.-stimulated delayed signal tranducer and activator of transcription 3 activation, atrial natriuretic factor expression, and cardiac myocyte morphology. J Biol Chem 276: 29490–29498, 2001. transgenic mice. J Clin Invest 107: 1127–1135, 2001.[Web of Science][Medline] induces cardiac myocyte growth but inhibits cardiac fibroblast proliferation in culture. J Clin Invest 95: 2555–2564, 1995.[Web of Science][Medline] and monocyte chemotactic and activating factor/monocyte chemoattractant protein-1 in the hypertrophied and failing heart with pressure overload. Circ Res 81: 664–671, 1997. modulates the growth and phenotype of neonatal rat cardiac myocytes. J Clin Invest 96: 1093–1099, 1995.[Web of Science][Medline]This article has been cited by other articles:
|
|
 |
|
  N. A. Turner, A. Das, P. Warburton, D. J. O'Regan, S. G. Ball, and K. E. Porter Interleukin-1{alpha} stimulates proinflammatory cytokine expression in human cardiac myofibroblasts Am J Physiol Heart Circ Physiol, September 1, 2009; 297(3): H1117 - H1127. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Jaffre, P. Bonnin, J. Callebert, H. Debbabi, V. Setola, S. Doly, L. Monassier, B. Mettauer, B. C. Blaxall, J.-M. Launay, et al. Serotonin and Angiotensin Receptors in Cardiac Fibroblasts Coregulate Adrenergic-Dependent Cardiac Hypertrophy Circ. Res., January 2, 2009; 104(1): 113 - 123. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. J. H. Smeets, B. E. J. Teunissen, A. Planavila, H. de Vogel-van den Bosch, P. H. M. Willemsen, G. J. van der Vusse, and M. van Bilsen Inflammatory Pathways Are Activated during Cardiomyocyte Hypertrophy and Attenuated by Peroxisome Proliferator-activated Receptors PPAR{alpha} and PPAR{delta} J. Biol. Chem., October 24, 2008; 283(43): 29109 - 29118. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Omland, M. H. Drazner, T. Ueland, M. Abedin, S. A. Murphy, P. Aukrust, and J. A. de Lemos Plasma Osteoprotegerin Levels in the General Population: Relation to Indices of Left Ventricular Structure and Function Hypertension, June 1, 2007; 49(6): 1392 - 1398. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
