A5037127640- Ion channel regulation and function
- Cardiac electrophysiology and arrhythmias
- Neuroscience and Neuropharmacology Research
- Neuroscience and Neural Engineering
- Cardiac Ischemia and Reperfusion
- Nicotinic Acetylcholine Receptors Study
- Receptor Mechanisms and Signaling
- Anesthesia and Neurotoxicity Research
- Cardiac Arrhythmias and Treatments
- Heart rate and cardiovascular health
- Cardiac Fibrosis and Remodeling
- Mesenchymal stem cell research
- Cardiac pacing and defibrillation studies
- Pain Mechanisms and Treatments
- RNA Interference and Gene Delivery
- Cell death mechanisms and regulation
- Nitric Oxide and Endothelin Effects
- Ion Channels and Receptors
- Heart Rate Variability and Autonomic Control
- Electrochemical Analysis and Applications
- Signaling Pathways in Disease
- Pancreatic function and diabetes
- Ion Transport and Channel Regulation
- Erythrocyte Function and Pathophysiology
- Photoreceptor and optogenetics research
Institut de Génomique Fonctionnelle
2015-2024
Centre National de la Recherche Scientifique
2012-2024
Inserm
2012-2024
Université de Montpellier
2013-2024
Laboratoire d'Excellence Canaux Ioniques d'Intérêt Thérapeutique
2012-2024
Laboratoire de Mathématiques d'Orsay
2012
Centre de Résonance Magnétique Biologique et Médicale
2009
Institut de Génétique Humaine
1998-2007
Centre Antoine Lacassagne
2007
Hôpital Lapeyronie
2007
The spontaneous activity of pacemaker cells in the sino-atrial node (SAN) controls heart rhythm and rate under physiological conditions. Pacemaker SAN is due to presence diastolic depolarization, a slow depolarization phase that drives membrane voltage from end an action potential threshold new potential. express wide array ionic channels, but we have limited knowledge about their functional role still do not know which channels play prominent generation depolarization. It thus important...
Even though sequencing of the mammalian genome has led to discovery a large number ionic channel genes, identification molecular determinants cellular electrical properties in different regions heart been rarely obtained. We developed high‐throughput approach capable simultaneously assessing expression pattern repertoires from mouse heart. By using large‐scale real‐time RT‐PCR, we have profiled 71 channels and related genes sinoatrial node (SAN), atrioventricular (AVN), atria (A) ventricles...
The generation of the mammalian heartbeat is a complex and vital function requiring multiple coordinated ionic channel activities. functional role low-voltage activated (LVA) T-type calcium channels in pacemaker activity sinoatrial node (SAN) is, to date, unresolved. Here we show that disruption gene coding for CaV3.1/alpha1G (cacna1g) abolishes current (I(Ca,T)) isolated cells from SAN atrioventricular without affecting L-type Ca2+ (I(Ca,L)). By using telemetric electrocardiograms on...
We describe here several novel properties of the human α<sub>1G</sub> subunit that forms T-type calcium channels. The partial intron/exon structure corresponding gene<i>CACNA1G</i> was defined and isoforms were identified, especially two exhibit a distinct III-IV loop: α<sub>1G-a</sub> α<sub>1G-b</sub>. Northern blot dot analyses indicated mRNA is predominantly expressed in brain, thalamus, cerebellum, substantia nigra. Additional experiments have also provided evidence at higher level...
In several types of neurons, firing is an intrinsic property produced by specific classes ion channels. Low‐voltage‐activated T‐type calcium channels (T‐channels), which activate with small membrane depolarizations, can generate burst and pacemaker activity. Here we have investigated the contribution to neuronal excitability cloned human T‐channel subunits. Using HEK‐293 cells transiently transfected α 1G (Ca V 3.1), 1H 3.2) 1I 3.3) subunits, describe significant differences among these...
Journal Article Architectural and functional asymmetry of the His–Purkinje system murine heart Get access Lucile Miquerol, Miquerol * aLaboratoire de Génétique et Physiologie du Développement, UMR 6545, Institut Biologie Développement Marseille, Université la Méditerranée, France *Corresponding author. Tel.: +33-4-9126-9734; fax: +33-4-9126-9726. Email address: [email protected] Search for other works by this author on: Oxford Academic PubMed Google Scholar Sonia Meysen, Meysen Matteo...
de niveau recherche, publiés ou non, émanant des établissements d'enseignement et recherche français étrangers, laboratoires publics privés.
The symptoms of irritable bowel syndrome (IBS) include significant abdominal pain and bloating. Current treatments are empirical often poorly efficacious, there is a need for the development new efficient analgesics aimed at IBS patients. T-type calcium channels have previously been validated as potential target to treat certain neuropathic pathologies. Here we report that encoded by Ca(V)3.2 isoform expressed in colonic nociceptive primary afferent neurons they contribute exaggerated...
Mechanosensitivity is an inherent property of virtually all cell types, allowing them to sense and respond physical environmental stimuli. Stretch-activated ion channels represent a class mechanosensitive proteins which allow cells rapidly changes in membrane tension; however their identity has remained elusive. The piezo genes have recently been identified as family stretch-activated channels. We set out determine the role piezo1 during zebrafish development. Here we report that...
Sino-atrial node (SAN) automaticity is an essential mechanism of heart rate generation that still not completely understood. Recent studies highlighted the importance intracellular Ca2+ ([Ca2+]i) dynamics during SAN pacemaker activity. Nevertheless, functional role voltage-dependent L-type channels in controlling [Ca2+]i release largely unexplored. Since Cav1.3 predominant channel isoform cells, we studied isolated cells and ex vivo preparations explanted from wild-type (WT) knockout (KO)...
Objective: We have investigated the properties of hyperpolarization-activated (If) current in pacemaker cells from mouse sino-atrial node (SAN). Methods: The If was studied isolated enzymatically SAN region adult C57BL6/J mice. whole-cell variation patch-clamp technique employed to investigate basic If. Results: In cells, density at −120 mV 18±2 pA/pF (n=23). not detected showing atrial-like morphology that were also found preparations (n=7). blocked by 5 mM Cs+, inhibited application μM...
Background In mammalian heart cells, Ca 2+ influx through voltage-gated L-type channels can be upregulated by high rates of stimulation. We have investigated this important adaptive regulation in human cardiomyocytes. Methods and Results Using the whole-cell patch-clamp technique, we found a frequency–induced upregulation (HFIUR) dihydropyridine-sensitive current (I ) I was potentiated graded manner with increasing stimulation between 0.3 5 Hz. Both moderate increase peak amplitude marked...
Summary Isolated atrial or ventricular human cardio-myocytes were dissociated from the heart of patients undergoing either open surgery (CS) cardiac transplantation (CT). L-type Ca currents recorded on cardiomyocytes CS CT by whole-cell voltage clamp technique. Although electrophysiologic properties current similar in and myocytes patients, cells had larger capacitance lower density. Whereas isoprenaline (Iso) induced an increase amplitude both cells, a serotoninergic agonist (5-HT4)...
We have cloned and expressed a human α<sub>1I</sub> subunit that encodes subtype of T-type calcium channels. The predicted protein is 95% homologous to its rat counterpart but has distinct COOH-terminal region. Its mRNA detected almost exclusively in the brain, as well adrenal thyroid glands. Calcium currents generated by functional expression α<sub>1G</sub> subunits HEK-293 cells were compared. current activated inactivated ∼10 mV more positively. Activation inactivation kinetics up six...