piperidines and Hypertrophy--Left-Ventricular

piperidines has been researched along with Hypertrophy--Left-Ventricular* in 12 studies

Other Studies

12 other study(ies) available for piperidines and Hypertrophy--Left-Ventricular

ArticleYear
Mitochondrial protective effects of PARP-inhibition in hypertension-induced myocardial remodeling and in stressed cardiomyocytes.
    Life sciences, 2021, Mar-01, Volume: 268

    During oxidative stress mitochondria become the main source of endogenous reactive oxygen species (ROS) production. In the present study, we aimed to clarify the effects of pharmacological PARP-1 inhibition on mitochondrial function and quality control processes.. L-2286, a quinazoline-derivative PARP inhibitor, protects against cardiovascular remodeling and heart failure by favorable modulation of signaling routes. We examined the effects of PARP-1 inhibition on mitochondrial quality control processes and function in vivo and in vitro. Spontaneously hypertensive rats (SHRs) were treated with L-2286 or placebo. In the in vitro model, 150 μM H. PARP-inhibition prevented the development of left ventricular hypertrophy in SHRs. The interfibrillar mitochondrial network were less fragmented, the average mitochondrial size was bigger and showed higher cristae density compared to untreated SHRs. Dynamin related protein 1 (Drp1) translocation and therefore the fission of mitochondria was inhibited by L-2286 treatment. Moreover, L-2286 treatment increased the amount of fusion proteins (Opa1, Mfn2), thus preserving structural stability. PARP-inhibition also preserved the mitochondrial genome integrity. In addition, the mitochondrial biogenesis was also enhanced due to L-2286 treatment, leading to an overall increase in the ATP production and improvement in survival of stressed cells.. Our results suggest that the modulation of mitochondrial dynamics and biogenesis can be a promising therapeutical target in hypertension-induced myocardial remodeling and heart failure.

    Topics: Animals; Cells, Cultured; Citrate (si)-Synthase; DNA, Mitochondrial; Electrocardiography; Glutathione; Hypertension; Hypertrophy, Left Ventricular; Male; Membrane Potential, Mitochondrial; Mitochondria, Heart; Mitochondrial Proteins; Myocytes, Cardiac; Natriuretic Peptide, Brain; Piperidines; Poly(ADP-ribose) Polymerase Inhibitors; Quinazolines; Rats, Inbred SHR; Rats, Wistar

2021
Restoration of Adiponectin-Connexin43 Signaling Mitigates Myocardial Inflammation and Dysfunction in Diabetic Female Rats.
    Journal of cardiovascular pharmacology, 2020, Volume: 75, Issue:3

    ur preclinical findings replicated women's hypersensitivity to type-2 diabetes mellitus (T2DM)-evoked cardiac dysfunction along with demonstrating estrogen (E2)-dependent disruption of the cardiac adiponectin (APN)-connexin43 (Cx43) signaling. Whether the latter molecular anomaly underlies this women's cardiovascular health problem remains unknown. We hypothesized that restoration of the disrupted APN-Cx43 signaling alleviates this sex/E2-dependent cardiac dysfunction in diabetic female rats. To test this hypothesis, we administered the adiponectin receptor 1 (AdipoR1) agonist AdipoRon (30 mg/kg/d for 10 days) to female sham operated (SO) and ovariectomized (OVX) rats, which exhibited and lacked the T2DM left ventricular (LV) dysfunction, respectively, when fed high-fat diet and received low dose streptozotocin regimen; nondiabetic control SO and OVX rats received control diet and vehicle for streptozotocin. In T2DM SO rats, LV dysfunction, AdipoRon mitigated: (1) LV hypertrophy, (2) reductions in fractional shortening, LV developed pressure, dP/dtmax, dP/dtmin, and Tau. In LV tissues of the same rats, AdipoRon reversed reduction in Cx43 and elevations in TNFα, heme-oxygenase 1 (HO-1), and circulating cardiovascular risk factor asymmetric dimethylarginine. The findings also revealed ovarian hormones independent effects of AdipoRon, which included dampening of the pro-oxidant enzyme HO-1. These novel findings yield new insight into a causal role for compromised APN-Cx43 signaling in the E2-dependent hypersensitivity to T2DM-evoked cardiac inflammation and dysfunction. Equally important, the findings identify restoration of Cx43 signaling as a viable therapeutic modality for alleviating this women's cardiovascular health-related problem.

    Topics: Adiponectin; Animals; Arginine; Connexin 43; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Diabetic Cardiomyopathies; Estradiol; Estrogen Receptor alpha; Female; Heme Oxygenase (Decyclizing); Hypertrophy, Left Ventricular; Ovariectomy; Piperidines; Rats, Wistar; Receptors, Adiponectin; Receptors, G-Protein-Coupled; Signal Transduction; Tumor Necrosis Factor-alpha; Ventricular Dysfunction, Left; Ventricular Function, Left; Ventricular Remodeling

2020
Alogliptin prevents diastolic dysfunction and preserves left ventricular mitochondrial function in diabetic rabbits.
    Cardiovascular diabetology, 2018, 12-27, Volume: 17, Issue:1

    There are increasing evidence that left ventricle diastolic dysfunction is the initial functional alteration in the diabetic myocardium. In this study, we hypothesized that alogliptin prevents diastolic dysfunction and preserves left ventricular mitochondrial function and structure in diabetic rabbits.. A total of 30 rabbits were randomized into control group (CON, n = 10), alloxan-induced diabetic group (DM, n = 10) and alogliptin-treated (12.5 mg/kd/day for 12 weeks) diabetic group (DM-A, n = 10). Echocardiographic and hemodynamic studies were performed in vivo. Mitochondrial morphology, respiratory function, membrane potential and reactive oxygen species (ROS) generation rate of left ventricular tissue were assessed. The serum concentrations of glucagon-like peptide-1, insulin, inflammatory and oxidative stress markers were measured. Protein expression of TGF-β1, NF-κB p65 and mitochondrial biogenesis related proteins were determined by Western blotting.. DM rabbits exhibited left ventricular hypertrophy, left atrial dilation, increased E/e' ratio and normal left ventricular ejection fraction. Elevated left ventricular end diastolic pressure combined with decreased maximal decreasing rate of left intraventricular pressure (- dp/dtmax) were observed. Alogliptin alleviated ventricular hypertrophy, interstitial fibrosis and diastolic dysfunction in diabetic rabbits. These changes were associated with decreased mitochondrial ROS production rate, prevented mitochondrial membrane depolarization and improved mitochondrial swelling. It also improved mitochondrial biogenesis by PGC-1α/NRF1/Tfam signaling pathway.. The DPP-4 inhibitor alogliptin prevents cardiac diastolic dysfunction by inhibiting ventricular remodeling, explicable by improved mitochondrial function and increased mitochondrial biogenesis.

    Topics: Animals; Diabetes Mellitus, Experimental; Diabetic Cardiomyopathies; Diastole; Dipeptidyl-Peptidase IV Inhibitors; Fibrosis; Hypertrophy, Left Ventricular; Membrane Potential, Mitochondrial; Mitochondria, Heart; Nuclear Respiratory Factor 1; Oxidative Stress; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Piperidines; Rabbits; Reactive Oxygen Species; Signal Transduction; Stroke Volume; Transcription Factors; Uracil; Ventricular Dysfunction, Left; Ventricular Function, Left; Ventricular Pressure; Ventricular Remodeling

2018
Activation of the Amino Acid Response Pathway Blunts the Effects of Cardiac Stress.
    Journal of the American Heart Association, 2017, May-09, Volume: 6, Issue:5

    The amino acid response (AAR) is an evolutionarily conserved protective mechanism activated by amino acid deficiency through a key kinase, general control nonderepressible 2. In addition to mobilizing amino acids, the AAR broadly affects gene and protein expression in a variety of pathways and elicits antifibrotic, autophagic, and anti-inflammatory activities. However, little is known regarding its role in cardiac stress. Our aim was to investigate the effects of halofuginone, a prolyl-tRNA synthetase inhibitor, on the AAR pathway in cardiac fibroblasts, cardiomyocytes, and in mouse models of cardiac stress and failure.. Consistent with its ability to inhibit prolyl-tRNA synthetase, halofuginone elicited a general control nonderepressible 2-dependent activation of the AAR pathway in cardiac fibroblasts as evidenced by activation of known AAR target genes, broad regulation of the transcriptome and proteome, and reversal by l-proline supplementation. Halofuginone was examined in 3 mouse models of cardiac stress: angiotensin II/phenylephrine, transverse aortic constriction, and acute ischemia reperfusion injury. It activated the AAR pathway in the heart, improved survival, pulmonary congestion, left ventricle remodeling/fibrosis, and left ventricular function, and rescued ischemic myocardium. In human cardiac fibroblasts, halofuginone profoundly reduced collagen deposition in a general control nonderepressible 2-dependent manner and suppressed the extracellular matrix proteome. In human induced pluripotent stem cell-derived cardiomyocytes, halofuginone blocked gene expression associated with endothelin-1-mediated activation of pathologic hypertrophy and restored autophagy in a general control nonderepressible 2/eIF2α-dependent manner.. Halofuginone activated the AAR pathway in the heart and attenuated the structural and functional effects of cardiac stress.

    Topics: Amino Acids; Amino Acyl-tRNA Synthetases; Animals; Autophagy; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Fibroblasts; Fibrosis; Heart Failure; Humans; Hypertrophy, Left Ventricular; Induced Pluripotent Stem Cells; Male; Mice, Inbred C57BL; Myocytes, Cardiac; Piperidines; Protein Serine-Threonine Kinases; Protein Synthesis Inhibitors; Quinazolinones; Stress, Physiological; Time Factors; Ventricular Function, Left; Ventricular Remodeling

2017
Effects of Long-term Blockade of Vasopressin Receptor Types 1a and 2 on Cardiac and Renal Damage in a Rat Model of Hypertensive Heart Failure.
    Journal of cardiovascular pharmacology, 2015, Volume: 66, Issue:5

    The effects of chronic blockade of vasopressin type 1a receptors (V1aR) and the additive effects of a type 2 receptor (V2R) antagonist on the treatment of hypertension-induced heart failure and renal injury remain to be unknown. In this study, Dahl salt-sensitive hypertensive rats were chronically treated with a vehicle (CONT), a V1aR antagonist (OPC21268; OPC), a V2R antagonist (tolvaptan; TOLV), or a combination of OPC21268 and tolvaptan (OPC/TOLV) from the pre-hypertrophic stage (6 weeks). No treatment altered blood pressure during the study. Significant improvements were seen in median survival for the OPC and TOLV, and the OPC/TOLV showed a further improvement in Kaplan-Meier analysis. Echocardiography showed suppressed left ventricular hypertrophy in the OPC and OPC/TOLV at 11 weeks with improved function in all treatment groups by 17 weeks. In all treatment groups, improvements were seen in the following: myocardial histological changes, creatinine clearance, urinary albumin excretion, and renal histopathologic damage. Also, key mRNA levels were suppressed (eg, endothelin-1 and collagen). In conclusion, chronic V1aR blockade ameliorated disease progression in this rat model, with additive benefits from the combination of V1aR and V2R antagonists. It was associated with protection of both myocardial and renal damage, independent of blood pressure.

    Topics: Animals; Antidiuretic Hormone Receptor Antagonists; Benzazepines; Disease Models, Animal; Drug Therapy, Combination; Fibrosis; Gene Expression Regulation; Heart Failure; Heart Ventricles; Hemodynamics; Hypertension; Hypertrophy, Left Ventricular; Kidney; Kidney Diseases; Male; Piperidines; Quinolones; Rats, Inbred Dahl; Receptors, Vasopressin; Time Factors; Tolvaptan; Ventricular Function, Left; Ventricular Remodeling

2015
PARP-inhibitor treatment prevents hypertension induced cardiac remodeling by favorable modulation of heat shock proteins, Akt-1/GSK-3β and several PKC isoforms.
    PloS one, 2014, Volume: 9, Issue:7

    Spontaneously hypertensive rat (SHR) is a suitable model for studies of the complications of hypertension. It is known that activation of poly(ADP-ribose) polymerase enzyme (PARP) plays an important role in the development of postinfarction as well as long-term hypertension induced heart failure. In this study, we examined whether PARP-inhibitor (L-2286) treatment could prevent the development of hypertensive cardiopathy in SHRs. 6-week-old SHR animals were treated with L-2286 (SHR-L group) or placebo (SHR-C group) for 24 weeks. Wistar-Kyoto rats were used as aged-matched, normotensive controls (WKY group). Echocardiography was performed, brain-derived natriuretic peptide (BNP) activity and blood pressure were determined at the end of the study. We detected the extent of fibrotic areas. The amount of heat-shock proteins (Hsps) and the phosphorylation state of Akt-1(Ser473), glycogen synthase kinase (GSK)-3β(Ser9), forkhead transcription factor (FKHR)(Ser256), mitogen activated protein kinases (MAPKs), and protein kinase C (PKC) isoenzymes were monitored. The elevated blood pressure in SHRs was not influenced by PARP-inhibitor treatment. Systolic left ventricular function and BNP activity did not differ among the three groups. L-2286 treatment decreased the marked left ventricular (LV) hypertrophy which was developed in SHRs. Interstitial collagen deposition was also decreased by L-2286 treatment. The phosphorylation of extracellular signal-regulated kinase (ERK)1/2(Thr183-Tyr185), Akt-1(Ser473), GSK-3β(Ser9), FKHR(Ser256), and PKC ε(Ser729) and the level of Hsp90 were increased, while the activity of PKC α/βII(Thr638/641), ζ/λ(410/403) were mitigated by L-2286 administration. We could detect signs of LV hypertrophy without congestive heart failure in SHR groups. This alteration was prevented by PARP inhibition. Our results suggest that PARP-inhibitor treatment has protective effect already in the early stage of hypertensive myocardial remodeling.

    Topics: Animals; Blood Pressure; Extracellular Signal-Regulated MAP Kinases; Forkhead Transcription Factors; Gene Expression Regulation; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Heart Failure; HSP90 Heat-Shock Proteins; Hypertension; Hypertrophy, Left Ventricular; Isoenzymes; Male; Natriuretic Peptide, Brain; Nerve Tissue Proteins; Phosphorylation; Piperidines; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Protein Kinase C; Proto-Oncogene Proteins c-akt; Quinazolines; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Signal Transduction

2014
KMUP-1 inhibits hypertension-induced left ventricular hypertrophy through regulation of nitric oxide synthases, ERK1/2, and calcineurin.
    The Kaohsiung journal of medical sciences, 2012, Volume: 28, Issue:11

    Hypertension can induce left ventricular hypertrophy (LVH), and the nitric oxide (NO) pathway plays an important role in the pathogenesis of cardiac hypertrophy. This study aimed to examine whether KMUP-1, a novel xanthine-based derivative, could inhibit LVH in spontaneously hypertensive rats (SHRs) and to investigate potential mechanisms underlying its antihypertrophic effects. Two groups of animals with chronic or subacute LVH were treated. In the chronic LVH group, KMUP-1 (10 or 30 mg/kg/d orally) was administered for 28 days to both normotensive rats and SHRs. In the subacute LVH group, KMUP-1 (0.5 mg/kg/d intraperitoneally) or sildenafil (0.7 mg/kg/d intraperitoneally) was administered for 10 days with or without co-treatment with the nitric oxide synthase (NOS) inhibitor N-omega-nitro-l-arginine (L-NNA; 20 mg/L orally). After treatment, the effects of KMUP-1 or sildenafil on hypertension, cardiac hypertrophy, survival, expression of the NO/soluble guanylate cyclase (sGC)/protein kinase G (NO/sGC/PKG) pathway in the aorta andleft ventricle, and calcineurin A/extracellular signal-regulated kinase 1/2 (ERK1/2) signaling in the left ventricle were examined. In the chronic LVH group, the SHRs developed hypertension with LVH over the 28 days. KMUP-1 attenuated the hypertension and LVH, increased survival rate, enhanced endothelial NOS/cyclic guanosine monophosphate/PKG (eNOS/cGMP/PKG) and decreased inducible NOS (iNOS) expression in the aorta and left ventricle of the SHRs. In the subacute LVH group, both KMUP-1 and sildenafil administered for 10 days attenuated the LVH in SHRs, with enhanced eNOS/cGMP/PKG and suppressed iNOS/calcineurin A/ERK1/2 expression in the left ventricle. In addition, both KMUP-1 and sildenafil attenuated L-NNA-induced LVH. KMUP-1 inhibition of hypertension-induced LVH with associated upregulation of eNOS, downregulation of iNOS in both the aorta and left ventricle, and attenuation of calcineurin A and ERK1/2 signaling in the left ventricle.

    Topics: Animals; Calcineurin; Hypertrophy, Left Ventricular; Male; MAP Kinase Signaling System; Nitric Oxide; Nitric Oxide Synthase; Piperidines; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Xanthines

2012
Orally active MMP-1 sparing α-tetrahydropyranyl and α-piperidinyl sulfone matrix metalloproteinase (MMP) inhibitors with efficacy in cancer, arthritis, and cardiovascular disease.
    Journal of medicinal chemistry, 2010, Sep-23, Volume: 53, Issue:18

    α-Sulfone-α-piperidine and α-tetrahydropyranyl hydroxamates were explored that are potent inhibitors of MMP's-2, -9, and -13 that spare MMP-1, with oral efficacy in inhibiting tumor growth in mice and left-ventricular hypertrophy in rats and in the bovine cartilage degradation ex vivo explant system. α-Piperidine 19v (SC-78080/SD-2590) was selected for development toward the initial indication of cancer, while α-piperidine and α-tetrahydropyranyl hydroxamates 19w (SC-77964) and 9i (SC-77774), respectively, were identified as backup compounds.

    Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Biological Availability; Cardiovascular Agents; Cartilage, Articular; Cattle; Crystallography, X-Ray; Humans; Hydroxamic Acids; Hypertrophy, Left Ventricular; Macaca fascicularis; Matrix Metalloproteinase Inhibitors; Mice; Mice, Nude; Models, Molecular; Molecular Structure; Piperidines; Pyrans; Rats; Structure-Activity Relationship; Sulfones; Xenograft Model Antitumor Assays

2010
PARP inhibition delays transition of hypertensive cardiopathy to heart failure in spontaneously hypertensive rats.
    Cardiovascular research, 2009, Aug-01, Volume: 83, Issue:3

    Oxidative stress followed by abnormal signalling can play a critical role in the development of long-term, high blood pressure-induced cardiac remodelling in heart failure (HF). Since oxidative stress-induced poly(ADP-ribose)polymerase (PARP) activation and cell death have been observed in several experimental models, we investigated the possibility that inhibition of nuclear PARP improves cardiac performance and delays transition from hypertensive cardiopathy to HF in a spontaneously hypertensive rat (SHR) model of HF.. SHRs were divided into two groups: one received no treatment (SHR-C) and the other (SHR-L) received 5 mg/kg/day L-2286 (PARP-inhibitor) orally for 46 weeks. A third group was a normotensive age-matched control group (CFY) and a fourth was a normotensive age-matched group receiving L-2286 treatment 5 mg/kg/day (CFY+L). At the beginning of the study, systolic function was similar in both CFY and SHR groups. In the SHR-C group at the end of the study, eccentric hypertrophy with poor left ventricular (LV) systolic function was observed, while PARP inhibitor treatment preserved systolic LV function. Due to these favourable changes, the survival rate of SHRs was significantly improved (P < 0.01) by the administration of the PARP inhibitor (L-2286). The PARP inhibitor used did not affect the elevated blood pressure of SHR rats, but moderated the level of plasma-BNP (P < 0.01) and favourably influenced all the measured gravimetric parameters (P < 0.05) and the extent of myocardial fibrosis (P < 0.05). The inhibition of PARP increased the phosporylation of Akt-1/GSK-3beta (P < 0.01), ERK 1/2 (P < 0.01), and PKC epsilon (P < 0.01), and decreased the phosphorylation of JNK (P < 0.05), p-38 MAPK (P < 0.01), PKC pan betaII and PKC zeta/lambda (P < 0.01), and PKC alpha/betaII and delta (P < 0.05).. These data demonstrate that chronic inhibition of PARP induces long-term favourable changes in the most important signalling pathways related to oxidative stress. PARP inhibition also prevents remodelling, preserves systolic function, and delays transition of hypertensive cardiopathy to HF in SHRs.

    Topics: Administration, Oral; Animals; Blood Pressure; Cardiovascular Agents; Disease Models, Animal; Disease Progression; Enzyme Inhibitors; Extracellular Signal-Regulated MAP Kinases; Fibrosis; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Heart Failure; Hypertension; Hypertrophy, Left Ventricular; Isoenzymes; JNK Mitogen-Activated Protein Kinases; Male; Myocardium; Natriuretic Peptide, Brain; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Piperidines; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Protein Kinase C; Proto-Oncogene Proteins c-akt; Quinazolines; Rats; Rats, Inbred SHR; Signal Transduction; Time Factors; Ventricular Function, Left; Ventricular Remodeling

2009
A nonpeptide, piperidine renin inhibitor provides renal and cardiac protection in double-transgenic mice expressing human renin and angiotensinogen genes.
    Cardiovascular drugs and therapy, 2008, Volume: 22, Issue:6

    Controlling hypertension by angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB), mechanisms that inhibit later pathway steps in the renin-angiotensin system (RAS), have clinically afforded protection against cardiac and renal disease.. In order to determine if blocking the RAS rate-limiting step of angiotensin II generation via renin inhibition could afford similar end organ protection in a human-relevant preclinical model, this study investigated the cardiac and renal effects of a nonpeptide, piperidine renin inhibitor (RI; 100 mg/kg/day PO) in double transgenic mice (dTGM) which express both human renin and angiotensinogen genes. RI was compared to the ARB, candesartan (3 mg/kg/day PO), and to the ACEI, enalapril (60 mg/kg/day PO) in a 4-week dosing paradigm. These doses of RI, ACEI and ARB were previously found to normalize mean blood pressure (MBP) to 110 + 3, 109 + 7 and 107 + 6 mmHg, respectively, after 1 day of treatment.. In the dTGM, PRA, plasma aldosterone, GFR, microalbuminuria and left ventricular free wall thickness (LVH) were higher than in the wild type C57BL/6 mice. Microalbuminuria and LVH were significantly reduced by 93% and 9% for the RI, 83% and 13% for enalapril and 73% and 6% for candesartan, respectively. PRA and aldosterone were reduced by the RI 56% and 23%, respectively. These results suggest that the RI provides protection against cardiac and renal disease, similar to ARB and ACEI.

    Topics: Administration, Oral; Albuminuria; Aldosterone; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Angiotensinogen; Animals; Benzimidazoles; Biphenyl Compounds; Blood Pressure; Cardiotonic Agents; Drug Administration Schedule; Enalapril; Female; Glomerular Filtration Rate; Humans; Hypertrophy, Left Ventricular; Kidney Diseases; Mice; Mice, Inbred C57BL; Mice, Transgenic; Molecular Structure; Piperidines; Quinolines; Renin; Renin-Angiotensin System; Tetrazoles; Time Factors; Ultrasonography

2008
E-4031 enhanced Ca2+ transient and ventricular myocytes contraction via reverse mode Na+/Ca2+ exchange in normal and hypertrophic rats.
    Acta pharmacologica Sinica, 2002, Volume: 23, Issue:9

    To study the effects of N-[4-[[1-[2-(6-methyl-2-pyridinyl)ethyl]-4-piperidinyl]carbonyl]phenyl]methanesulfonamide dihydrochloride dihydrate (E-4031), a specific Ik blocker, on Ca2+ transient and cell contraction of normal and hypertrophied rat ventricular myocytes.. Electrically triggered Ca2+ transient and cell shortening were measured simultaneously using the Ion Imaging System with charge coupled digital (CCD) camera.. E-4031 (10 micromol/L) increased Ca2+ transient and cell shortening from (210+/-49) and (3.0+/-0.8) micron to (245+/-47) and (3.6+/-1.0) micron, respectively (P<0.05) in normal cardiomyocytes and from (196+/-54) and (3.0+/-1.3) micron to (240+/-49) and (3.6+/-1.3) micron respectively (P<0.05) in hypertrophied cardiomyocytes, while did not change calcium sensitivity in both groups. KB-R7943 completely blocked the activating effects induced by E-4031 in both of normal and hypertrophied cardiomyocytes. Nicardipine did not block the increasing effects of E-4031.. E-4031 increased Ca2+ transient and cell contraction via stimulating reverse mode of Na+/Ca2+ exchange while without influencing calcium sensitivity. These effects were more notable in hypertrophied cardiomyocytes than in normal myocytes.

    Topics: Animals; Anti-Arrhythmia Agents; Calcium; Electric Stimulation; Hypertrophy, Left Ventricular; Myocardial Contraction; Piperidines; Pyridines; Rats; Rats, Wistar; Sodium-Calcium Exchanger

2002
Effects of ACE inhibition on left ventricular failure and oxidative stress in Dahl salt-sensitive rats.
    Journal of cardiovascular pharmacology, 2001, Volume: 37, Issue:6

    Dahl salt-sensitive (DS) rats fed high-salt diet exert compensated left ventricular (LV) hypertrophy and eventually develop heart failure. Oxidative stress has been shown to be involved in myocardial remodeling and failure and thus might play an important role in this transition from hypertrophy to failure. We measured the amount of reactive oxygen species (ROS) in the myocardium from DS rats by using electron spin resonance spectroscopy with 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl (hydroxy-TEMPO) and also examined the effects of chronic angiotensin-converting enzyme (ACE) inhibition on the transition. We divided DS rats (5 weeks old, 150-200 g) into three groups: low-salt (0.3% NaCl) diet for 10 weeks (LS group), high-salt (8% NaCl) diet for 10 weeks (HS-10+V group), and high-salt diet and cilazapril (10 mg/kg body weight per day) started after 5 weeks of high-salt diet and maintained for 5 weeks (HS-10+Cil group). Systolic blood pressure (mm Hg) was significantly elevated in the HS-10+V (229+/-5) and HS-10+Cil (209+/-5) groups compared with the LS group (141+/-2). The amount of myocardial ROS was not changed after 5 weeks of high-salt diet, but significantly increased in HS-10+V rats compared with LS rats, and was abolished in the HS-10+Cil group. HS-10+V rats exerted the clinical signs of heart failure, including increased lung weight and pleural effusion, associated with LV hypertrophy and LV cavity dilatation. In the HS-10+Cil group, signs of heart failure were significantly attenuated despite only a modest reduction in systolic blood pressure (-20 mm Hg). The progression of LV failure after hypertrophy in high-salt-loaded DS hypertensive rats was associated with increased myocardial ROS, and ACE inhibitor could prevent this transition from compensated hypertrophy to failure.

    Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Blood Pressure; Cilazapril; Electron Spin Resonance Spectroscopy; Heart Failure; Hypertrophy, Left Ventricular; Male; Oxidative Stress; Piperidines; Rats; Rats, Inbred Dahl; Reactive Oxygen Species; Sodium Chloride, Dietary; Survival Rate; Ventricular Dysfunction, Left

2001