Blockade of AT1 receptors and Na+/H+exchanger and LV dysfunction after myocardial infarction in rats

1999 ◽  
Vol 277 (2) ◽  
pp. H610-H616 ◽  
Author(s):  
Marcel Ruzicka ◽  
Baoxue Yuan ◽  
Frans H. H. Leenen
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Cardiac Remodeling ◽  
Left Ventricular ◽  
Lv Function ◽  
Coronary Artery Ligation ◽  
Ang Ii ◽  
Artery Ligation ◽  
Volume Load ◽  
Lv Dysfunction

Mechanical stretch, ANG II, and α1-receptor stimulation may contribute to cardiac remodeling after myocardial infarction (MI). Each of these mechanisms involves different signaling pathways for the cellular hypertrophic response. All three also activate the Na+/H+exchanger. In the present study we evaluated the hypothesis that activation of the Na+/H+exchanger is involved in parallel with other signaling mechanisms for ANG II. Three days before coronary artery ligation, rats were randomly allocated to no treatment or treatment with amiloride, losartan, or amiloride and losartan in combination. Four weeks after coronary artery ligation, left ventricular (LV) function was assessed from in vivo resting cardiac pressures, hemodynamic responses to cardiac volume and pressure load, and cardiac remodeling by in vitro pressure-volume curves and LV and right ventricle (RV) weight. Amiloride and losartan given alone to a similar extent attenuated the shift of the pressure-volume curve to the right. This effect was significantly more pronounced with amiloride and losartan in combination. Each drug alone to a minor extent improved LV responses to pressure and volume load. However, with amiloride and losartan in combination, close-to-normal responses to pressure and volume load were observed. Losartan and amiloride alone had only a small effect on development of RV hypertrophy after MI but in combination completely prevented the RV hypertrophy. Amiloride and losartan appear to be complementary in prevention of cardiac remodeling and LV dysfunction after MI. This finding suggests that, besides ANG II, other mechanisms activating the Na+/H+exchanger contribute to cardiac remodeling after MI.

scholarly journals Clofibrate Treatment Decreases Inflammation and Reverses Myocardial Infarction-Induced Remodelation in a Rodent Experimental Model

Molecules ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 270 ◽  
Author(s):  
Luz Ibarra-Lara ◽  
María Sánchez-Aguilar ◽  
Elizabeth Soria-Castro ◽  
Jesús Vargas-Barrón ◽  
Francisco Roldán ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Cardiac Remodeling ◽  
Ventricular Remodeling ◽  
Ex Vivo ◽  
Left Ventricular ◽  
Coronary Artery Ligation ◽  
Cardiac Damage ◽  
Artery Ligation ◽  
Apoptotic Proteins

Myocardial infarction (MI) initiates an inflammatory response that promotes both beneficial and deleterious effects. The early response helps the myocardium to remove damaged tissue; however, a prolonged later response brings cardiac remodeling characterized by functional, metabolic, and structural pathological changes. Current pharmacological treatments have failed to reverse ischemic-induced cardiac damage. Therefore, our aim was to study if clofibrate treatment was capable of decreasing inflammation and apoptosis, and reverse ventricular remodeling and MI-induced functional damage. Male Wistar rats were assigned to (1) Sham coronary artery ligation (Sham) or (2) Coronary artery ligation (MI). Seven days post-MI, animals were further divided to receive vehicle (V) or clofibrate (100 mg/kg, C) for 7 days. The expression of IL-6, TNF-α, and inflammatory related molecules ICAM-1, VCAM-1, MMP-2 and -9, nuclear NF-kB, and iNOS, were elevated in MI-V. These inflammatory biomarkers decreased in MI-C. Also, apoptotic proteins (Bax and pBad) were elevated in MI-V, while clofibrate augmented anti-apoptotic proteins (Bcl-2 and 14-3-3ε). Clofibrate also protected MI-induced changes in ultra-structure. The ex vivo evaluation of myocardial functioning showed that left ventricular pressure and mechanical work decreased in infarcted rats; clofibrate treatment raised those parameters to control values. Echocardiogram showed that clofibrate partially reduced LV dilation. In conclusion, clofibrate decreases cardiac remodeling, decreases inflammatory molecules, and partly preserves myocardial diameters.

scholarly journals Protective and Therapeutic Effects of Chinese Medicine Formula Jiajian Yunvjian on Experimental Cardiac Remodeling after Myocardial Infarction Induced by Coronary Artery Ligation

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Jun Du ◽  
Wei-liang Gu ◽  
Chang-xun Chen ◽  
Ying Wang ◽  
Jian Lv
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Chinese Medicine ◽  
Cardiac Remodeling ◽  
Heart Weight ◽  
Coronary Artery Ligation ◽  
Ang Ii ◽  
Artery Ligation ◽  
Weight Index ◽  
Chinese Medicine Formula

Introduction. This study was designed to explore the effect and mechanism of a classic Chinese medicine formula Jiajian Yunvjian (JJYNJ) on cardiac remodeling. Cardiac remodeling after myocardial infarction (MI) model was achieved by coronary artery ligation (CAL).Methodology. When dosed orally once daily, the effects of JJYNJ on hemodynamics, left ventricular weight index (LVWI), heart weight index (HWI), concentration, and gene expression of neuroendocrine factors as well as the histomorphological observation were determined.Results. After 4 weeks, mild cardiac remodeling in CAL group was characterized compared with sham group, but after 4 weeks of treatment of JJYNJ, hemodynamics improved, HWI reduced, and circulating angiotensin II (Ang II), endothelin-1 (ET-1), tumor necrosis factor-α(TNF-α), and hydroxyproline (Hyp) concentrations as well as Ang II receptor type 1 (AT1R) mRNA, transforming growth factorβ1(TGF-β1) mRNA, and TNF-αmRNA levels in myocardium were lower than in CAL group. Decreased plasma aldosterone (ALD) concentration, cross-sectional area of cardiomyocyte, collagen volume fraction (CVF), collagen types I and III, perivascular collagen area (PVCA), and upregulated nitric oxide (NO) levels were observed at the same time.Conclusions. These findings suggest that JJYNJ may have a protective and therapeutic function on cardiac remodeling related to MI.

Regulation of components of the brain and cardiac renin-angiotensin systems by 17β-estradiol after myocardial infarction in female rats

2006 ◽  
Vol 291 (1) ◽  
pp. R155-R162 ◽  
Author(s):  
Stephanie A. Dean ◽  
Junhui Tan ◽  
Roselyn White ◽  
Edward R. O’Brien ◽  
Frans H. H. Leenen
Keyword(s):  
Myocardial Infarction ◽  
Left Ventricular ◽  
Female Rats ◽  
Lv Function ◽  
Coronary Artery Ligation ◽  
Brain Nuclei ◽  
Renin Angiotensin ◽  
Lv Dysfunction ◽  
17Β Estradiol ◽  
The Brain

The present study tested the hypothesis that 17β-estradiol (E2) inhibits increases in angiotensin-converting enzyme (ACE) and ANG II type 1 receptor (AT1R) in the brain and heart after myocardial infarction (MI) and, thereby, inhibits development of left ventricular (LV) dysfunction after MI. Age-matched female Wistar rats were treated as follows: 1) no surgery (ovary intact), 2) ovariectomy + subcutaneous vehicle treatment (OVX + Veh), or 3) OVX + subcutaneous administration of a high dose of E2 (OVX + high-E2). After 2 wk, rats were randomly assigned to coronary artery ligation (MI) and sham operation groups and studied after 3 wk. E2 status did not affect LV function in sham rats. At 2–3 wk after MI, impairment of LV function was similar across MI groups, as measured by echocardiography and direct LV catheterization. LV ACE mRNA abundance and activity were increased severalfold in all MI groups compared with respective sham animals and to similar levels across MI groups. In most brain nuclei, ACE and AT1R densities increased after MI. Unexpectedly, compared with the respective sham groups the relative increase was clearest (20–40%) in OVX + high-E2 MI rats, somewhat less (10–15%) in ovary-intact MI rats, and least (<10–15%) in OVX + Veh MI rats. However, because in the sham group brain ACE and AT1R densities increased in the OVX + Veh rats and decreased in the OVX + high-E2 rats compared with the ovary-intact rats, actual ACE and AT1R densities in most brain nuclei were modestly higher (<20%) in OVX + Veh MI rats than in the other two MI groups. Thus E2 does not inhibit upregulation of ACE in the LV after MI and amplifies the percent increases in ACE and AT1R densities in brain nuclei after MI, despite E2-induced downregulation in sham rats. Consistent with these minor variations in the tissue renin-angiotensin system, during the initial post-MI phase, E2 appears not to enhance or hinder the development of LV dysfunction.

Comparison of Myocardial Infarction with Sequential Ligation of the Left Anterior Descending Artery and Its Diagonal Branch in Dogs and Sheep

2003 ◽  
Vol 26 (4) ◽  
pp. 351-357 ◽  
Author(s):  
W.G. Kim ◽  
Y.C. Shin ◽  
S.W. Hwang ◽  
C. Lee ◽  
C.Y. Na
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Pulmonary Artery ◽  
Left Ventricular ◽  
Coronary Artery Ligation ◽  
Suitable Model ◽  
Artery Ligation ◽  
Diagonal Branch ◽  
Left Anterior Descending Artery ◽  
Arterial Blood

We report a comparison of the effects of myocardial infarction in dogs and sheep using sequential ligation of the left anterior descending artery (LAD) and its diagonal branch (DA), with hemodynamic, ultrasonographic and pathological evaluations. Five animals were used in each group. After surgical preparation, the LAD was ligated at a point approximately 40% of the distance from the apex to the base of the heart, and after one hour, the DA was ligated at the same level. Hemodynamic and ultrasonographic measurements were performed preligation, 30 minutes after LAD ligation, and 1 hour after DA ligation. As a control, two animals in each group were used for the simultaneous ligation of the LAD and the DA. Two months after the coronary ligation, the animals were evaluated as previously, and killed for postmortem examination of their hearts. All seven animals in the dog group survived the experimental procedures, while in the sheep group only animals with sequential ligation of the LAD and DA survived. Statistically significant decreases in systemic arterial blood pressure and cardiac output, and an increase in the pulmonary artery capillary wedge pressure (PACWP) were observed one hour after sequential ligation of the LAD and its DA in the sheep, while only systemic arterial pressures decreased in the dog. Ultrasonographic analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all sheep, but in no dogs. Data two months after coronary artery ligation showed significant increases in central venous pressure, pulmonary artery pressure, and PACWP in the sheep, but not in the dog. Left ventricular end-diastolic dimension and left ventricular end-systolic dimension in ultrasonographic studies were also increased only in the sheep. Pathologically, the well-demarcated thin-walled transmural anteroseptal infarcts with chamber enlargement were clearly seen in all specimens of sheep, and only-mild-to-moderate chamber enlargements with endocardial fibrosis were observed in the dog hearts. In conclusion, this study confirms that the dog is not a suitable model for myocardial infarction with failure by coronary artery ligation despite negligent operative mortality, when compared directly with an ovine model.

Depletion of cardiac 14-3-3η protein adversely influences pathologic cardiac remodeling during myocardial infarction after coronary artery ligation in mice

2016 ◽  
Vol 202 ◽  
pp. 146-153 ◽  
Author(s):  
Remya Sreedhar ◽  
Somasundaram Arumugam ◽  
Rajarajan A. Thandavarayan ◽  
Vijayasree V. Giridharan ◽  
Vengadeshprabhu Karuppagounder ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Cardiac Remodeling ◽  
Coronary Artery Ligation ◽  
Artery Ligation

Changes in cardiac ANG II postmyocardial infarction in rats: effects of nephrectomy and ACE inhibitors

1999 ◽  
Vol 276 (1) ◽  
pp. H317-H325 ◽  
Author(s):  
Frans H. H. Leenen ◽  
Vaclav Skarda ◽  
Baoxue Yuan ◽  
Roselyn White
Keyword(s):  
Coronary Artery ◽  
Ace Inhibitors ◽  
Time Course ◽  
Cardiac Tissue ◽  
Left Ventricular ◽  
Coronary Artery Ligation ◽  
Ang Ii ◽  
Artery Ligation ◽  
Conscious Rats ◽  
Postmyocardial Infarction

We evaluated in rats the time course of changes in cardiac versus plasma ANG I and II postmyocardial infarction (MI) and the effects of nephrectomy and angiotensin-converting enzyme (ACE) inhibitors on the early changes post-MI. Acute coronary artery ligation was induced in conscious rats using the two-stage model, and plasma and cardiac tissue were obtained shortly (6 h, 1 and 3 days) and chronically (1, 4, and 8–9 wk) after MI. In an additional group of rats, bilateral nephrectomy was performed 18 h before the coronary artery ligation, and samples were obtained at 6 h post-MI. Furthermore, in two additional groups of rats, treatment with enalapril and quinapril was started 3 days before the ligation, and samples were obtained at 1 or 3 days post-MI. In these groups of rats, plasma and left ventricular (LV) (infarct and infarct free) ANG I and II were measured by RIA after separation on HPLC. In control rats, plasma ANG I and II showed a clear increase at 6 h post-MI but subsequently only minor increases were observed. In contrast, LV ANG II showed major increases at 6 h and 1 day post-MI, which had returned to normal by 3 days in the infarct-free LV and after 1(–2) wk in the infarct LV. LV ANG I showed a more gradual increase and remained elevated in the infarct up to 8–9 wk. Nephrectomy preceding the MI lowered ANG I and II in plasma but enhanced their increases in the heart at 6 h post-MI. Both ACE inhibitors decreased plasma ANG II associated with large increases in plasma ANG I. They also inhibited the increases in LV ANG II in both the infarct and infarct-free LV at 1 and 3 days post-MI with however no significant increase in LV ANG I. In conclusion, induction of a MI in conscious rats leads to rapid and marked, but only short-lived, increases in cardiac tissue ANG II in both the infarct and infarct-free parts of the LV. Pretreatment with ACE inhibitors, but not nephrectomy, blocks this increase. Local production appears to play a major role in the increases in cardiac ANG II post-MI.

Midterm Surgical Outcomes for ALCAPA Repair in Infants and Children

2021 ◽  
Author(s):  
Renjie Hu ◽  
Wen Zhang ◽  
Xiafeng Yu ◽  
Hongbin Zhu ◽  
Haibo Zhang ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Mitral Valve ◽  
Mitral Valve Regurgitation ◽  
Left Ventricular ◽  
Surgical Correction ◽  
Circulatory Support ◽  
Lv Function ◽  
Coronary Artery Ligation ◽  
Artery Ligation

Abstract Background Surgical correction of an anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) has been associated with excellent survival during recent years. The purpose of this study was to evaluate the effectiveness of reimplantation of the coronary artery and to investigate the recovery of postoperative cardiac and mitral valve (MV) function. Methods From 2005 to 2015, 80 patients who had ALCAPA received surgical correction. Among them, 49 were infants. The median patient age was 7.8 months. Operative strategies included reimplantation of the coronary artery in 71 patients, the Takeuchi procedure in another 7 patients, and coronary artery ligation in the remaining 2 patients. Results There were 11 hospital deaths and 2 late deaths. Six patients required intraoperative or postoperative mechanical circulatory support. A significant improvement in the ejection fraction (EF) and shortening fraction (SF) was present in all surviving patients at discharge, at a 3-month follow-up and at a 1-year follow-up. MV function improved gradually after surgical repair with no late secondary intervention. Conclusions The repair of ALCAPA can be accomplished by establishment of a dual-coronary system, which offers an acceptable mortality rate and will rarely require a second surgery. Left ventricular (LV) recovery is a progressive process, especially for infants with impaired LV function. Concomitant MV annuloplasty is safe and reliable and can be performed as necessary in patients with moderate or severe mitral valve regurgitation.

Abstract 3659: High-Mobility Group Box 1 Restores Cardiac Dysfunction after Myocardial Infarction in Transgenic Mice

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Tatsuro Kitahara ◽  
Yasuchika Takeishi ◽  
Tetsuro Shishido ◽  
Satoshi Suzuki ◽  
Shigehiko Kato ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Cardiac Dysfunction ◽  
Nuclear Dna ◽  
Inflammatory Responses ◽  
High Mobility ◽  
Left Ventricular ◽  
High Mobility Group ◽  
Coronary Artery Ligation ◽  
Artery Ligation

High-mobility group box 1 (HMGB1) is a nuclear DNA-binding protein and is released from necrotic cells, inducing inflammatory responses and promoting tissue repair and angiogenesis. To test the hypothesis that HMGB1 enhances angiogenesis and restores cardiac dysfunction after myocardial infarction, we generated transgenic mouse with cardiac specific overexpression of HMGB1 (HMGB1-Tg) using α-myosin heavy chain (MHC) promoter. The left anterior descending coronary artery was ligated in HMGB1-Tg and wild-type littermate (Wt) mice. After coronary artery ligation, HMGB1 was released into circulation from the necrotic cardiomyocytes of HMGB1 overexpressing hearts. The size of myocardial infarction was smaller in HMGB1-Tg than in Wt mice (figure ). Echocardiography and cardiac catheterization demonstrated that cardiac remodeling and dysfunction after myocardial infarction were prevented in HMGB1-Tg mice compared to Wt mice. Furthermore, survival rate after myocardial infarction in HMGB1-Tg mice was higher than that in Wt mice (figure ). Immunohistochemical staining revealed that capillary and arteriole formations after myocardial infarction were enhanced in HMGB1-Tg mice. We demonstrated the first in vivo evidence that HMGB1 enhances angiogenesis, restores cardiac dysfunction, and improves survival after myocardial infarction. These results may provide a novel therapeutic approach for left ventricular dysfunction after myocardial infarction.

Sign in / Sign up

Export Citation Format

Share Document