Muller A, Chabbert C. TRPV4 channels mediate the infrared laserevoked response in sensory neurons. Infrared laser irradiation has been established as an appropriate stimulus for primary sensory neurons under conditions where sensory receptor cells are impaired or lost. Yet, development of clinical applications has been impeded by lack of information about the molecular mechanisms underlying the laser-induced neural response. Here, we directly address this question through pharmacological

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... erization of the biological response evoked by midinfrared irradiation of isolated retinal and vestibular ganglion cells from rodents. Whole cell patch-clamp recordings reveal that both voltagegated calcium and sodium channels contribute to the laser-evoked neuronal voltage variations (LEVV). In addition, selective blockade of the LEVV by micromolar concentrations of ruthenium red and RN 1734 identifies thermosensitive transient receptor potential vanilloid channels as the primary effectors of the chain reaction triggered by midinfrared laser irradiation. These results have the potential to facilitate greatly the design of future prosthetic devices aimed at restoring neurosensory capacities in disabled patients. transient receptor potential vanilloid 4; prosthesis MATERIALS AND METHODS Animals. Mice of the C57BL/6 strain and Wistar rats (Centre d'Elevage Janvier, Le Genest-Saint-Isle, France) were used in the study. All procedures were carried out in accordance with the French/ European Communities Council Directive 86/609/EEC. Cell preparations. Retinal ganglion cells (RGCs) were isolated from postnatal days 2-4 (P2-P4) mice using the Thy-1 antibodymediated plate adhesion immunopanning technique, and their specificity was confirmed using RGC Brn3a immunoassay according to previously described procedures (Kamei et al. 2005) . VGCs were explanted from P5-P9 rats and dissociated according to previously described procedures (Dayanithi et al. 2007 ).