Search results for " Myocytes"
showing 10 items of 11 documents
Different muscarinic receptor subtypes modulate proliferation of primary human detrusor smooth muscle cells via Akt/PI3K and map kinases.
2013
While acetylcholine (ACh) and muscarinic receptors in the bladder are mainly known for their role in the regulation of smooth muscle contractility, in other tissues they are involved in tissue remodelling and promote cell growth and proliferation. In the present study we have used primary cultures of human detrusor smooth muscle cells (HDSMCs), in order to investigate the role of muscarinic receptors in HDSMC proliferation. Samples were obtained as discarded tissue from men >65 years undergoing radical cystectomy for bladder cancer and cut in pieces that were either immediately frozen or placed in culture medium for the cell culture establishment. HDSMCs were isolated from samples, propagat…
A multicentre case control study on complicated coeliac disease: two different patterns of natural history, two different prognoses
2014
Background: Coeliac disease is a common enteropathy characterized by an increased mortality mainly due to its complications. The natural history of complicated coeliac disease is characterised by two different types of course: patients with a new diagnosis of coeliac disease that do not improve despite a strict gluten-free diet (type A cases) and previously diagnosed coeliac patients that initially improved on a gluten-free diet but then relapsed despite a strict diet (type B cases). Our aim was to study the prognosis and survival of A and B cases. Methods: Clinical and laboratory data from coeliac patients who later developed complications (A and B cases) and sex- and age-matched coeliac p…
Lysed Erythrocyte Membranes Promote Vascular Calcification
2019
Background: Intraplaque hemorrhage promotes atherosclerosis progression, and erythrocytes may contribute to this process. In this study we examined the effects of red blood cells on smooth muscle cell mineralization and vascular calcification and the possible mechanisms involved. Methods: Erythrocytes were isolated from human and murine whole blood. Intact and lysed erythrocytes and their membrane fraction or specific erythrocyte components were examined in vitro using diverse calcification assays, ex vivo by using the murine aortic ring calcification model, and in vivo after murine erythrocyte membrane injection into neointimal lesions of hypercholesterolemic apolipoprotein E–deficient mi…
Implication du récepteur 5-HT4 cardiaque humain dans la fibrillation auriculaire : rôle d’auto-anticorps dirigés contre ce récepteur ?
2004
The human cardiac 5-HT4 receptor was cloned in 1997. It is functional only in atrial myocytes where it is positively coupled via Gs to the adenylate cyclase, activates the cAMP-dependent protein kinase (PKA) and in consequence phosphorylates a variety of intracellular proteins implicated in excitation-contraction coupling. A number of studies suggest a role for the 5-HT4 receptor in the maintenance or elongation of atrial fibrillation. It is now accepted that certain cardiac pathologies involve auto-immune processes. Antibodies directed against the second extracellular loop of a number of cardiac G-protein linked receptors have been found. The human cardiac 5-HT4 receptor could therefore al…
The Amino-Terminal Domain of GRK5 Inhibits Cardiac Hypertrophy through the Regulation of Calcium-Calmodulin Dependent Transcription Factors.
2018
We have recently demonstrated that the amino-terminal domain of G protein coupled receptor kinase (GRK) type 5, (GRK5-NT) inhibits NFκB activity in cardiac cells leading to a significant amelioration of LVH. Since GRK5-NT is known to bind calmodulin, this study aimed to evaluate the functional role of GRK5-NT in the regulation of calcium-calmodulin-dependent transcription factors. We found that the overexpression of GRK5-NT in cardiomyoblasts significantly reduced the activation and the nuclear translocation of NFAT and its cofactor GATA-4 in response to phenylephrine (PE). These results were confirmed in vivo in spontaneously hypertensive rats (SHR), in which intramyocardial adenovirus-med…
Atrial natriuretic peptide and CD34 overexpression in human idiopathic dilated cardiomyopathies.
2007
Idiopathic dilated cardiomyopathy (IDCM) is a primary myocardial disease of unknown cause characterized by ventricular chamber enlargement with impaired contractile function. In familial forms of IDCM, mutations of genes coding for cytoskeletal proteins related to force transmission, such as dystrophin, cardiac actin, desmin, and delta-sarcoglycan, have been identified. Here, we report the data of a retrospective investigation carried out to evaluate the expression of atrial natriuretic peptide (ANP), CD34, troponin T and nestin in the myocardium of patients affected with IDCM. Formalin-fixed and paraffin-embedded consecutive tissue sections from the ventricular wall of 10 human normal hear…
Carbon monoxide improves cardiac energetics and safeguards the heart during reperfusion after cardiopulmonary bypass in pigs
2004
Ischemia-reperfusion injury, a clinical problem during cardiac surgery, involves worsened adenosine trisphosphate (ATP) generation and damage to the heart. We studied carbon monoxide ( CO) pretreatment, proven valuable in rodents but not previously tested in large animals, for its effects on pig hearts subjected to cardiopulmonary bypass with cardioplegic arrest. Hearts of CO-treated pigs showed significantly higher ATP and phosphocreatine levels, less interstitial edema, and apoptosis of cardiomyocytes and required fewer defibrillations after bypass. We conclude that treatment with CO improves the energy status, prevents edema formation and apoptosis, and facilitates recovery in a clinical…
Immunohistochemical marker for Na+ CP type Vα (C-20) and heterozygous nonsense SCN5A mutation W822X in a sudden cardiac death induced by mild anaphyl…
2009
A sudden death likely due to mild anaphylactic reaction in a young man is described. Autoptic, histologic, immunohistochemical, and laboratory findings were strongly consistent with the diagnosis of a mild anaphylactic reaction. Genetic molecular analysis, performed on formalin-fixed, paraffin-embedded tissues, showed a mutation described as W822X in a family with electrocardiographic pattern typical of Brugada Syndrome. It results in a nonsense mutation generating a truncated form of the channel protein. The mutation is due to a point substitution of a guanine with an adenine residue (G2466A). Immunohistochemistry and laser scanning confocal microscopy on sections from heart formalin-fixed…
Ranolazine-Mediated Attenuation of Mechanoelectric Feedback in Atrial Myocyte Monolayers.
2020
[EN] Background Mechanical stretch increases Na(+)inflow into myocytes, related to mechanisms including stretch-activated channels or Na+/H(+)exchanger activation, involving Ca(2+)increase that leads to changes in electrophysiological properties favoring arrhythmia induction. Ranolazine is an antianginal drug with confirmed beneficial effects against cardiac arrhythmias associated with the augmentation ofI(NaL)current and Ca(2+)overload. Objective This study investigates the effects of mechanical stretch on activation patterns in atrial cell monolayers and its pharmacological response to ranolazine. Methods Confluent HL-1 cells were cultured in silicone membrane plates and were stretched to…
MiR-133 Modulates the β1Adrenergic Receptor Transduction Cascade.
2014
Rationale : The sympathetic nervous system plays a fundamental role in the regulation of myocardial function. During chronic pressure overload, overactivation of the sympathetic nervous system induces the release of catecholamines, which activate β-adrenergic receptors in cardiomyocytes and lead to increased heart rate and cardiac contractility. However, chronic stimulation of β-adrenergic receptors leads to impaired cardiac function, and β-blockers are widely used as therapeutic agents for the treatment of cardiac disease. MicroRNA-133 (miR-133) is highly expressed in the myocardium and is involved in controlling cardiac function through regulation of messenger RNA translation/stability. …