temocapril-hydrochloride and Heart-Failure

We are investigating whether aldosterone breakthrough negatively impacts on the antiproteinuric effects of angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin II receptor blockers (ARB).. We examine the role of aldosterone breakthrough in 43 normotensive, proteinuric (0.7 +/- 0.3 g/day) outpatients (aged 41.5 +/- 10.9 years) with immunoglobulin A nephropathy (IgAN) accompanied by stable renal function (creatinine clearance >50 mL/min). The patients were treated with temocapril (1 mg; n = 14), losartan (12.5 mg; n = 16), or a combination therapy (n = 13) for 12 months. We prospectively evaluated blood pressure (BP), urinary protein excretion (UPE), biochemical parameters and the renin-angiotensin-aldosterone system before and after 12 months of treatment.. Although the overall plasma aldosterone concentrations values did not change after any of the treatments administered for 12 months, they eventually increased in 23 (temocapril, seven patients; losartan, eight patients; combination, seven patients) of the 43 patients (53.4%; aldosterone breakthrough), and fell in the remainder (46.6%). Blood pressure and renal function did not differ among the three groups at 12 months. In contrast, UPE was significantly higher in patients with, than without aldosterone breakthrough during temocapril and losartan administration. However, combination therapy induced a more remarkable reduction in UPE regardless of aldosterone breakthrough.. A combination of ACE inhibitors and ARB in normotensive patients with IgAN produces a more profound decrease in proteinuria than either monotherapy. This additive antiproteinuric effect is not dependent on aldosterone breakthrough. Additional larger, prospective, randomized studies will be needed for general acceptance of this strategy.

Topics: Adult; Aldosterone; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Blood Pressure; Drug Therapy, Combination; Female; Glomerulonephritis, IGA; Heart Failure; Humans; Losartan; Male; Middle Aged; Prospective Studies; Proteinuria; Thiazepines

Promoted myocardial stiffening has a crucial role in the transition to overt diastolic heart failure (DHF) in hypertensive hearts and is attributed to progressive ventricular fibrosis. Previous studies revealed the effects of an angiotensin II type 1 receptor blocker (ARB) and an angiotensin-converting enzyme inhibitor (ACEI) on the synthesis and degradation of collagens in the other phenotype of heart failure, systolic heart failure, which has a different pathophysiology; however, little is known about their effects in DHF.. To investigate effects of an ACEI and an ARB on the regulatory system of ventricular fibrosis in hypertensive DHF.. Dahl salt-sensitive rats fed a diet containing 8% NaCl from age 7 weeks (DHF model) were divided into three groups: six untreated rats, six rats treated with a subdepressor dose of an ARB, candesartan cilexetil (1 mg/kg per day), from age 8 weeks, and six rats treated with a subdepress or dose of an ACEI, temocapril hydrochloride (0.2 mg/kg per day), from age 8 weeks. Six Dahl salt-sensitive rats fed on normal chow served as controls. Data were collected when animals were aged 20 weeks.. The administration of an ARB or an ACEI inhibited ventricular fibrosis to the same degree. The ACEI decreased the level of type I collagen mRNA, but the decrease was less than that induced by the ARB. The difference in collagen synthesis was probably cancelled out by that in degradation: both in-vitro and in-situ zymography showed that gelatinase activity was greater in the rats treated with the ACEI than in those treated with the ARB.. An ARB and an ACEI inhibited ventricular fibrosis through different mechanisms in hypertensive DHF.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Animals; Benzimidazoles; Biphenyl Compounds; Collagen Type I; Echocardiography; Fibrosis; Gene Expression; Heart Failure; Heart Ventricles; Hemodynamics; Hypertension; Male; Rats; Rats, Inbred Dahl; Tetrazoles; Thiazepines; Ventricular Dysfunction, Left

Diastolic heart failure (DHF) has become a social burden; however, evidences leading to its therapeutic strategy are lacking. This study investigated effects of addition of angiotensin II type 1 receptor blocker (ARB) to angiotensin-converting enzyme inhibitor (ACEI) at advanced stage of DHF in hypertensive rats. Dahl salt-sensitive rats fed 8% NaCl diet from age 7 weeks served as DHF model, and those fed a normal chow served as control. The DHF model rats were arbitrarily assigned to 3 treatment regimens at age 17 weeks: ACEI (temocapril 0.4 mg/kg per day), combination of ACEI (temocapril 0.2 mg/kg per day) with ARB (olmesartan 0.3 mg/kg per day), or placebo. At age 17 weeks, this model represents progressive ventricular hypertrophy and fibrosis, relaxation abnormality, and myocardial stiffening. Data were collected at age 20 weeks. As compared with the monotherapy with ACEI, the addition of ARB induced more prominent suppression of ventricular hypertrophy and fibrosis, leading to suppression of myocardial stiffening, improvement of relaxation, and inhibition of hemodynamic deterioration. Such benefits were associated with greater decreases in reactive oxygen species (ROS) generation, macrophage infiltration, and gene expression of transforming growth factor (TGF)-beta(1) and interleukin (IL)-1beta, but not with changes in gene expression of monocyte chemoattractant protein (MCP)-1 and tumor necrosis factor (TNF)-alpha. Thus, ARB added to ACEI provides more benefits as compared with ACEI alone in DHF when initiated at an advanced stage. The additive effects are likely provided through more prominent suppression of ROS generation and inflammatory changes without effects on expression of MCP-1 and TNF-alpha.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Calcium-Binding Proteins; Calcium-Transporting ATPases; Diastole; Disease Progression; Drug Therapy, Combination; Extracellular Matrix; Heart Failure; Heart Ventricles; Hemodynamics; Hypertension; Imidazoles; Inflammation; Male; Olmesartan Medoxomil; Rats; Rats, Inbred Dahl; Reactive Oxygen Species; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Tetrazoles; Thiazepines; Ventricular Dysfunction, Left

Both angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 (AT1) receptor blockers have been demonstrated to improve symptoms and prognosis in heart failure (HF). We compared the effects of ACE inhibition and AT1 receptor blockade on myocardial beta-adrenoceptor desensitization in rabbits with HF established 3 weeks after myocardial infarction (MI) with left circumflex coronary artery ligation. Rabbits with MI were randomized to no treatment, the ACE inhibitor temocapril (0.5 mg/kg/day) or AT1 receptor blocker valsartan (3 mg/kg/day). Echocardiographic examinations showed that, relative to rabbits with untreated MI, rabbits receiving temocapril or valsartan had a limitation of cardiac remodeling and prevention of the development of systolic dysfunction. Circulating plasma norepinephrine levels that were markedly elevated in MI animals were strongly inhibited by temocapril or valsartan therapy. beta-Adrenoceptor density, beta-adrenoceptor proportion showing high-affinity agonist binding, and basal and isoproterenol-stimulated adenylate cyclase activities were significantly reduced in MI rabbits. These defects were similarly reversed by temocapril or valsartan. Importantly, as found in human HF, myocardial protein levels of beta-adrenoceptor kinase 1 and G(i alpha) were significantly elevated in MI rabbits, suggesting that these molecules are contributing to the defects in myocardial beta-adrenoceptor signaling. The expression levels of these molecules were normalized equally by both treatments. The results suggest that pharmacologically different interventions in the renin-angiotensin system can equivalently improve the derangements in the beta-adrenoceptor signaling system in the failing heart. This may be important for the beneficial effects of these agents in HF.

Topics: Adenylyl Cyclases; Adrenergic beta-Agonists; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Animals; beta-Adrenergic Receptor Kinases; Blotting, Western; Cyclic AMP-Dependent Protein Kinases; Down-Regulation; Echocardiography; GTP-Binding Protein alpha Subunits, Gi-Go; Heart Failure; Hemodynamics; In Vitro Techniques; Iodocyanopindolol; Male; Membranes; Myocardial Infarction; Myocardium; Norepinephrine; Organ Size; Rabbits; Radioligand Assay; Receptor, Angiotensin, Type 1; Receptors, Adrenergic, beta; Signal Transduction; Thiazepines

Congestive heart failure with left ventricular (LV) diastolic dysfunction and preserved systolic function, i.e. diastolic heart failure (DHF), is often observed in hypertensive patients. Although angiotensin converting enzyme (ACE) inhibitors are widely used as antihypertensive therapy, there is a continued controversy about long-term effect of ACE inhibition on diastolic function. The current study was designed to elucidate a therapeutic effect of ACE inhibitor, temocapril, administration initiated after LV hypertrophy (LVH) and diastolic dysfunction are evident.. Dahl salt sensitive rats fed on 8% NaCl diet from 7 weeks (hypertensive DHF model) were studied at 13 weeks (n=6) or at 19 weeks following chronic administration of a subdepressor dose of temocapril (0.2 mg/kg/day, TEM(+), n=6) or placebo (TEM(-), n=7) from 13 weeks.. Compensatory LVH was associated with prolonged time constant of LV relaxation (Tau) at 13 weeks. In TEM(-), progression of LVH and fibrosis and elevation of LV end diastolic pressure were observed at 19 weeks. Administration of temocapril from 13 weeks prevented the further progression of LVH and fibrosis, attenuated increases in myocardial stiffness constant and Tau, and prevented the development of DHF. These effects were accompanied with the attenuation of decreases in sarcoplasmic reticulum calcium(2+)-ATPase 2a and phosphorylated phospholamban and of hypertrophic signalings' upregulation.. This study demonstrated that chronic administration of temocapril exerts a therapeutic effect on diastolic dysfunction and prevents the transition to DHF even if initiated after appearance of LVH and diastolic dysfunction.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Antihypertensive Agents; Calcium-Binding Proteins; Calcium-Transporting ATPases; Disease Progression; Fibrosis; Gene Expression Regulation; Heart Failure; Hemodynamics; Hypertension; Hypertrophy, Left Ventricular; Male; Rats; Rats, Inbred Dahl; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Thiazepines; Ventricular Function, Left

In view of their mutual crosstalk, the roles of angiotensin II (Ang II) and endothelin-1 (ET-1) in the myocardium are assumed to be synergistic and supplemental.. In the phase of compensated left ventricular (LV) hypertrophy of Dahl salt-sensitive rats, Ang II peptide and the ACE mRNA in the LV were increased by 1.6- and 3.8-fold, respectively. In contrast, ET-1 peptide and the preproET-1 mRNA remained unchanged. In subsequent congestive heart failure (CHF), Ang II and ACE mRNA did not show further increases. But ET-1 and the mRNA were increased de novo by 5.3- and 4.1-fold, respectively. In ascending aorta-banded rats, the local activations of Ang II and ET-1 also showed a differential time course between LV hypertrophy and CHF. Long-term treatments of Dahl salt-sensitive rats with temocapril (an ACE inhibitor) and with bosentan (a mixed ET receptor blocker) equally improved long-term survival. Temocapril reduced the LV/body weight ratio and ameliorated LV fractional shortening. Conversely, although bosentan equally improved fractional shortening, it did not reduce the increase in LV mass. Combined treatment with these 2 drugs further ameliorated the animal's survival without additional decreases in systolic pressure.. The pathophysiological roles in the myocardium during the transition to CHF differ qualitatively between Ang II and ET-1. Thus, long-term therapy with a combination of ACE inhibition and ET antagonism may provide a new approach for heart failure in humans.

Topics: Angiotensin II; Angiotensinogen; Animals; Antihypertensive Agents; Blood Pressure; Bosentan; Disease Progression; Endothelin-1; Endothelins; Gene Expression Regulation; Heart Failure; Heart Ventricles; Hemodynamics; Hypertrophy, Left Ventricular; Male; Organ Size; Peptidyl-Dipeptidase A; Protein Precursors; Rats; Rats, Inbred Dahl; Rats, Sprague-Dawley; RNA, Messenger; Sulfonamides; Survival Analysis; Thiazepines; Time Factors

We studied an alteration of calcineurin expression in the heart and its modification by cyclosporin A and an ACE inhibitor, temocapril, using Dahl salt-sensitive (DS) rats with hypertensive left ventricular hypertrophy (LVH) and congestive heart failure (CHF). Calcineurin protein expression in the LV myocardium was increased in the LVH stage, but then decreased during CHF transition. Chronic cyclosporin A treatment (10 mg/kg/day), which inhibits calcineurin activity, could not block the increases of LV weight and dimensions and did not improve the LV systolic function during the CHF transition. In contrast, chronic temocapril treatment (20 mg/kg/day) restored the downregulation of calcineurin expression, but progression of the hypertrophic process was inhibited. Therefore, cardiac calcineurin is increased in the hypertensive LVH and may be involved in the development of the adaptive hypertrophic process. However, calcineurin expression is downregulated during CHF transition and may no longer play a major role in the pathogenesis of myocardial hypertrophy in the failing hearts.

Topics: Adaptation, Physiological; Angiotensin-Converting Enzyme Inhibitors; Animals; Blotting, Western; Body Weight; Calcineurin; Calcineurin Inhibitors; Cyclosporine; Disease Progression; Down-Regulation; Electrocardiography; Heart Failure; Hemodynamics; Hypertension; Hypertrophy; Myocardium; Rats; Rats, Inbred Dahl; Thiazepines