Decreased expression of cardiac sarcoplasmic reticulum Ca2+-pump ATPase in congestive heart failure due to myocardial infarction

1996 ◽  
Vol 163-164 (1) ◽  
pp. 285-290 ◽  
Author(s):  
Angel Zarain-Herzberg ◽  
Nasir Afzal ◽  
Vijayan Elimban ◽  
Naranjan S. Dhalla
Keyword(s):  
Myocardial Infarction ◽  
Heart Failure ◽  
Congestive Heart Failure ◽  
Sarcoplasmic Reticulum ◽  
Cardiac Sarcoplasmic Reticulum

Influence of long-term treatment of imidapril on mortality, cardiac function, and gene expression in congestive heart failure due to myocardial infarction

2004 ◽  
Vol 82 (12) ◽  
pp. 1118-1127 ◽  
Author(s):  
Bin Ren ◽  
Qiming Shao ◽  
Pallab K Ganguly ◽  
Paramjit S Tappia ◽  
Nobuakira Takeda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Myocardial Infarction ◽  
Heart Failure ◽  
Congestive Heart Failure ◽  
Sarcoplasmic Reticulum ◽  
Cardiac Function ◽  
Term Treatment ◽  
Cardiac Performance ◽  
Long Term Treatment

Although it is generally accepted that the efficacy of imidapril, an angiotensin-converting enzyme inhibitor, in congestive heart failure (CHF) is due to improvement of hemodynamic parameters, the significance of its effect on gene expression for sarcolemma (SL) and sarcoplasmic reticulum (SR) proteins has not been fully understood. In this study, we examined the effects of long-term treatment of imidapril on mortality, cardiac function, and gene expression for SL Na+/K+ ATPase and Na+–Ca2+ exchanger as well as SR Ca2+ pump ATPase, Ca2+ release channel (ryanodine receptor), phospholamban, and calsequestrin in CHF due to myocardial infarction. Heart failure subsequent to myocardial infarction was induced by occluding the left coronary artery in rats, and treatment with imidapril (1 mg·kg–1·day–1) was started orally at the end of 3 weeks after surgery and continued for 37 weeks. The animals were assessed hemody nam ically and the heart and lung were examined morphologically. Some hearts were immediately frozen at –70 °C for the isolation of RNA as well as SL and SR membranes. The mortality of imidapril-treated animals due to heart failure was 31% whereas that of the untreated heart failure group was 64%. Imidapril treatment improved cardiac performance, attenuated cardiac remodeling, and reduced morphological changes in the heart and lung. The depressed SL Na+/K+ ATPase and increased SL Na+–Ca2+ exchange activities as well as reduced SR Ca2+ pump and SR Ca2+ release activities in the failing hearts were partially prevented by imidapril. Although changes in gene expression for SL Na+/K+ ATPase isoforms as well as Na+–Ca2+ exchanger and SR phospholamban were attenuated by treatments with imidapril, no alterations in mRNA levels for SR Ca2+ pump proteins and Ca2+ release channels were seen in the untreated or treated rats with heart failure. These results suggest that the beneficial effects of imidapril in CHF may be due to improvements in cardiac performance and changes in SL gene expression.Key words: sarcolemmal Na+/K+ ATPase, Na+–Ca2+ exchange, sarcoplasmic reticulum, heart failure, ACE inhibition.

Changes in skeletal muscle SR Ca2+ pump in congestive heart failure due to myocardial infarction are prevented by angiotensin II blockade

2004 ◽  
Vol 82 (7) ◽  
pp. 438-447 ◽  
Author(s):  
Kanu R Shah ◽  
Pallab K Ganguly ◽  
Thomas Netticadan ◽  
Amarjit S Arneja ◽  
Naranjan S Dhalla
Keyword(s):  
Myocardial Infarction ◽  
Heart Failure ◽  
Skeletal Muscle ◽  
Congestive Heart Failure ◽  
Sarcoplasmic Reticulum ◽  
Muscle Fatigue ◽  
Ace Inhibitors ◽  
Renin Angiotensin System ◽  
Exercise Intolerance ◽  
Angiotensin System

In order to understand the mechanisms of exercise intolerance and muscle fatigue, which are commonly observed in congestive heart failure, we studied sarcoplasmic reticulum (SR) Ca2+-transport in the hind-leg skeletal muscle of rats subjected to myocardial infarction (MI). Sham-operated animals were used for comparison. On one hand, the maximal velocities (Vmax) for both SR Ca2+-uptake and Ca2+-stimulated ATPase activities in skeletal muscle of rats at 8 weeks of MI were higher than those of controls. On the other hand, the Vmax values for both SR Ca2+-uptake and Ca2+-stimulated ATPase activities were decreased significantly at 16 weeks of MI when compared with controls. These alterations in Ca2+-transport activities were not associated with any change in the affinity (1/Ka) of the SR Ca2+-pump for Ca2+. Furthermore, the stimulation of SR Ca2+-stimulated ATPase activity by cyclic AMP-dependent protein kinase was not altered at 8 or 16 weeks of MI when compared with the respective control values. Treatment of 3-week infarcted animals with angiotensin-converting enzyme (ACE) inhibitors such as captopril, imidapril, and enalapril or an angiotensin receptor (AT1R) antagonist, losartan, for a period of 13 weeks not only attenuated changes in left ventricular function but also prevented defects in SR Ca2+-pump in skeletal muscle. These results indicate that the skeletal muscle SR Ca2+-transport is altered in a biphasic manner in heart failure due to MI. It is suggested that the initial increase in SR Ca2+-pump activity in skeletal muscle may be compensatory whereas the depression at late stages of MI may play a role in exercise intolerance and muscle fatigue in congestive heart failure. Furthermore, the improvements in the skeletal muscle SR Ca2+-transport by ACE inhibitors may be due to the decreased activity of renin-angiotensin system in congestive heart failure.Key words: skeletal muscle, sarcoplasmic reticulum, Ca2+-transport, SR Ca2+-pump, congestive heart failure, renin-angiotensin system.

scholarly journals Trends in mortality, co-morbidity and treatment after acute myocardial infarction in patients with rheumatoid arthritis 1998–2013

2020 ◽  
Vol 9 (8) ◽  
pp. 931-938 ◽  
Author(s):  
Mattias Skielta ◽  
Lars Söderström ◽  
Solbritt Rantapää-Dahlqvist ◽  
Solveig W Jonsson ◽  
Thomas Mooe
Keyword(s):  
Rheumatoid Arthritis ◽  
Myocardial Infarction ◽  
Heart Failure ◽  
Atrial Fibrillation ◽  
Acute Myocardial Infarction ◽  
Congestive Heart Failure ◽  
Cox Regression Analysis ◽  
Co Morbidity ◽  
One Year ◽  
Over Time

Aims: Rheumatoid arthritis may influence the outcome after an acute myocardial infarction. We aimed to compare trends in one-year mortality, co-morbidities and treatments after a first acute myocardial infarction in patients with rheumatoid arthritis versus non-rheumatoid arthritis patients during 1998–2013. Furthermore, we wanted to identify characteristics associated with mortality. Methods and results: Data for 245,377 patients with a first acute myocardial infarction were drawn from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions for 1998–2013. In total, 4268 patients were diagnosed with rheumatoid arthritis. Kaplan-Meier analysis was used to study mortality trends over time and multivariable Cox regression analysis was used to identify variables associated with mortality. The one-year mortality in rheumatoid arthritis patients was initially lower compared to non-rheumatoid arthritis patients (14.7% versus 19.7%) but thereafter increased above that in non-rheumatoid arthritis patients (17.1% versus 13.5%). In rheumatoid arthritis patients the mean age at admission and the prevalence of atrial fibrillation increased over time. Congestive heart failure decreased more in non-rheumatoid arthritis than in rheumatoid arthritis patients. Congestive heart failure, atrial fibrillation, kidney failure, rheumatoid arthritis, prior diabetes mellitus and hypertension were associated with significantly higher one-year mortality during the study period 1998–2013. Conclusions: The decrease in one-year mortality after acute myocardial infarction in non-rheumatoid arthritis patients was not applicable to rheumatoid arthritis patients. This could partly be explained by an increased age at acute myocardial infarction onset and unfavourable trends with increased atrial fibrillation and congestive heart failure in rheumatoid arthritis. Rheumatoid arthritis per se was associated with a significantly worse prognosis.

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