A5078135475- Cardiac electrophysiology and arrhythmias
- Ion channel regulation and function
- Neuroscience and Neural Engineering
- Receptor Mechanisms and Signaling
- Phosphodiesterase function and regulation
- Analytical Chemistry and Sensors
- Cardiovascular Function and Risk Factors
- Electrochemical Analysis and Applications
- Optical Imaging and Spectroscopy Techniques
- Nitric Oxide and Endothelin Effects
- Pharmacological Effects and Assays
- Photoreceptor and optogenetics research
- Cardiac Ischemia and Reperfusion
- Advanced MRI Techniques and Applications
- Heart Failure Treatment and Management
- Cardiovascular and exercise physiology
- Essential Oils and Antimicrobial Activity
- Phytochemistry and Biological Activities
- Mitochondrial Function and Pathology
- Photoacoustic and Ultrasonic Imaging
- Cardiac pacing and defibrillation studies
- Heart Rate Variability and Autonomic Control
- Neuroscience and Neuropharmacology Research
- Pulmonary Hypertension Research and Treatments
- ATP Synthase and ATPases Research
Lithuanian University of Health Sciences
2013-2023
Inserm
1996-2006
Université Paris-Sud
2002-2006
Laboratory Signaling and Cardiovascular Pathophysiology
2004
Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion
2002
Université Paris Cité
1996-2001
University of Nevada, Reno
1991
The role of cAMP subcellular compartmentation in the progress beta-adrenergic stimulation cardiac L-type calcium current (ICa) was investigated by using a method based on use whole-cell patch-clamp recording and double capillary for extracellular microperfusion. Frog ventricular cells were sealed at both ends to two pipettes positioned approximately halfway between mouths capillaries that separated 5-micron thin wall. ICa could be inhibited one half or other omitting Ca2+ from solution...
Abstract Patients with short QT syndrome (SQTS) may present syncope, ventricular fibrillation or sudden cardiac death. Six SQTS susceptibility genes, encoding cation channels, explain <25% of cases. Here we identify a missense mutation in the anion exchanger (AE3)-encoding SLC4A3 gene two unrelated families SQTS. The causes reduced surface expression AE3 and membrane bicarbonate transport. Slc4a3 knockdown zebrafish increased pH i , QTc, systolic duration, which is rescued by wildtype but...
Graphical Abstract figure legend HCN channels play an evolutionarily conserved pacemaker role in renal pelvic smooth muscle (RPSM) of lower and higher order mammals. The function hyperpolarization-activated cation (HCN) pacemakers remains controversial. Renal trigger contractions that expel waste from the kidney, have been localized to these tissues. To date, however, mechanisms underlying RPSM activity remain elusive. was investigated both (top left) (bottom mammalian models, which exhibit...
1 The regulation of L-type Ca2+ current (ICa) by the two nitric oxide (NO) donors sodium nitroprusside (SNP, μm to mm) and (±)-S-nitroso-N-acetylpenicillamine (SNAP, 3 or 10 μm) was investigated in frog ventricular myocytes using double voltage clamp double-barrelled microperfusion techniques. 2 SNP SNAP depressed isoprenaline (ISO, 10-100 nm)- forskolin (FSK, μm)-mediated stimulation ICa via cGMP activation cGMP-stimulated phosphodiesterase (PDE2). Complete inhibition ISO (100 nm) response...
The whole-cell patch-clamp and intracellular perfusion techniques were used for studying the effects of a beta-2 adrenergic receptor activation on L-type Ca current (ICa) in frog ventricular myocytes. agonist zinterol increased ICa concentration-dependent manner with an EC50 (i.e., concentration at which response was 50% maximum) 2.2 nM. effect essentially independent membrane potential. stimulatory competitively antagonized by ICI 118,551, antagonist. maximal comparable amplitude to...
The role of cyclic nucleotide phosphodiesterase (PDE) isoforms in the beta2-adrenergic stimulation L-type Ca2+ current (ICa,L) was investigated frog ventricular myocytes using double patch-clamp and double-barrelled microperfusion techniques. Isoprenaline (ISO, 1 nM to 10 microM) applied on one half cell, either alone or presence PDE inhibitors, local distant responses ICa,L were used determine gradient vs. cAMP concentration (alpha). IBMX (100 microM), a non-selective inhibitor, reduced...
The cAMP-dependent regulation of ion channels was studied by using the whole-cell configuration patch clamp technique. In isolated cardiac ventricular myocytes, beta-adrenergically regulated Cl- current (ICl) exhibited an unusual dependence on Na+, such that replacement extracellular Na+ with compounds as tetramethylammonium, choline, Tris, or N-methyl-D-glucamine resulted in a reduction amplitude without changing reversal potential. Replacement tetramethylammonium also reduced magnitude...
This review analyzes the structure and regulation mechanisms of voltagedependent L-type Ca2+ channel in heart. channels heart are composed four different polypeptide subunits, pore-forming subunit a1 is most important part channel. In cardiac myocytes, enter cell cytoplasm from extracellular space mainly through channels; these very system uptake regulation. responsible for activation sarcoplasmic reticulum (RyR2) force muscle contraction generation heart; hence, activity depends on...
The beta-adrenergic cascade is severely impaired in heart failure (HF), part because of a reduction the activity two dominant cardiac adenylyl cyclase (AC) isoforms, AC5 and AC6. Hence, cardiac-directed AC overexpression conceivable therapeutic strategy HF. In this study, we explored consequences at cellular organ level expression human AC8 transgenic mouse line AC8TG. Unlike AC6, which are inhibited by intracellular Ca2+, stimulated Ca2+-calmodulin. Langendorff perfused hearts from AC8TG...
The whole‐cell patch‐clamp was used for studying the effects of various β 1 ‐ and 2 ‐adrenoceptor agonists antagonists on L‐type Ca current ( I ) in frog ventricular myocytes. Dose‐response curves isoprenaline (non selective β‐agonist), salbutamol (β ‐agonist), dobutamine ‐agonist) were obtained absence presence concentrations ICI 118551 ‐antagonist), metoprolol ‐antagonist) xamoterol (partial to derive EC 50 (i.e. concentration β‐agonist at which response 50% maximum) E max (the maximal...
Voltage-sensitive fluorescent dyes have become a major tool in cardiac and neuro-electrophysiology. Achieving high signal-to-noise ratios requires increased illumination intensities, which may cause photobleaching phototoxicity. The optimal range of intensities varies for different must be evaluated individually. We evaluate two dyes: di-4-ANBDQBS (excitation 660 nm) di-4-ANEPPS 532 the guinea pig heart. light intensity from 0.1 to 5 mW/mm 2 , with upper limit at 10 times above values...
Background Because of the optical features heart tissue, and electrical action potentials are only moderately associated, especially when near-infrared dyes used in mapping (OM) studies. Objective By simultaneously recording transmural (APs) (OAPs), we aimed to evaluate contributions both influences shape OAP upstroke. Methods Results A standard glass microelectrode OM, using an fluorescent dye (di-4-ANBDQBS), were record APs OAPs a Langendorff-perfused rabbit during atrial, endocardial,...
1. The effects of acetylcholine (ACh) on the L‐type Ca2+ current (ICa) stimulated by isoprenaline (Iso) or forskolin (Fsk) were examined in frog ventricular myocytes using whole‐cell patch‐clamp technique and a double capillary for extracellular microperfusion. 2. exposure one half cell to 1 microM Iso produced half‐maximal increase ICa since subsequent application other induced an additional effect nearly same amplitude. Similarly, addition ACh only exposed both halves reduced approximately...
Summary Acute myocardial infarction is one of the major causes mortality worldwide. For regeneration rabbit heart after experimentally induced we used autologous skeletal myoblasts ( SM s) due to their high proliferative potential, resistance ischaemia and absence immunological ethical concerns. The cells were characterized with muscle‐specific myogenic markers. Cell transplantation was performed by injection cell suspension (0.5 ml) containing approximately 6 million into zone. animals...
Elsholtzia ciliata essential oil (E. ciliata) has been reported to have an impact on the cardiovascular system. However, its toxicity remains unknown. Therefore, objective of this investigation was evaluate toxicological aspects E. extract. Male Balb/c mice were subjected either acute (a single dose administered for 24 h) or sub-chronic (daily 60 days) intraperitoneal injections The assessed blood hematological/biochemical profiles, mitochondrial functions, and histopathological changes....
β-adrenergic receptors (β-ARs) mediate the positive inotropic effects of catecholamines by cAMP-dependent phosphorylation L-type Ca(2+) channels (LTCCs), which provide for initiation and regulation cell contraction. The overall effect cAMP-modulating agents on cardiac calcium current (I Ca,L) contraction depends basal activity LTCCs which, in turn, activities key enzymes involved cAMP signaling cascade. Our work is a comparative study demonstrating differences β-ARs, adenylyl cyclase,...
Abstract Indocyanine green (ICG) fluorescent dye has been approved by the FDA for use in medical diagnostics. Recently, we demonstrated that ICG voltage-sensitive properties with a dual-component (fast and slow) response Langendorff-perfused rabbit heart. Here, extended our studies showing different spectral of both components analysis fractional change fluorescence to voltage changes. We used light from four LEDs obtain excitation; emission was measured using an EMCCD camera band-pass...
This study investigates the development of spatiotemporal pattern action potential alternans during acute regional ischemia. Experiments were carried out in isolated Langendorff-perfused rabbit heart using a combination optical mapping and microelectrode recordings. The significantly changed over time had biphasic character reaching maximum at 6-9 min after occlusion. Phase I (3-11 minutes ischemia) is characterized by rapid increase magnitude expansion territory. followed gradual decline...
Despite the wide application of carvacrol (CAR) in medicines, dietary supplements, and foods, there is still insufficient electrophysiological data on mechanisms action CAR, particularly with regard to heart function. Therefore, this study, we attempted elucidate whether whose inhibitory effect both cardiac vascular TRPM7 L-type Ca 2+ currents has been demonstrated previously, could modify electrical activity. We used a combination optical mapping microelectrode techniques track potentials...