17 research outputs found
Interactions between NTS2 neurotensin and opioid receptors on two nociceptive responses assessed on the hot plate test in mice.
International audienc
Pharmacological isolation of the pulmonary veins in the rat.
Prix de Meilleur Presentation en Physiologie attribué à Pierre Bredeloux.National audienc
Biological targets involved in a primary manner in the mechanisms of action of antidepressant drugs
Rôle médiateur de la régulation émotionnelle entre TSPT et addiction à l’alimentation
National audienc
Structural heterogeneity of the rat pulmonary vein myocardium: consequences on intracellular calcium dynamics and arrhythmogenic potential
Abstract Mechanisms underlying ectopic activity in the pulmonary vein (PV) which triggers paroxysmal atrial fibrillation are unknown. Although several studies have suggested that calcium signalling might be involved in these arrhythmias, little is known about calcium cycling in PV cardiomyocytes (CM). We found that individual PV CM showed a wide range of transverse tubular incidence and organization, going from their virtual absence, as described in atrial CM, to well transversally organised tubular systems, like in ventricular CM. These different types of CM were found in groups scattered throughout the tissue. The variability of the tubular system was associated with cell to cell heterogeneity of calcium channel (Cav1.2) localisation and, thereby, of Cav1.2-Ryanodine receptor coupling. This was responsible for multiple forms of PV CM calcium transient. Spontaneous calcium sparks and waves were not only more abundant in PV CM than in LA CM but also associated with a higher depolarising current. In conclusion, compared with either the atrium or the ventricle, PV myocardium presents marked structural and functional heterogeneity