TRP is the most recently discovered family of ion channels and display the largest structure and function diversity among ion channels. Most TRP channels are key elements in sensory cells, where they are involved in the response to a broad range of external stimuli such as light, sound, chemicals, temperature and touch. In addition, cells detect changes in their local environment, like osmolarity and oxidative stress, by means of TRP channels. They have been found in eukaryotes like yeasts, worms, insects, fishes, birds, and mammals. In mammals, they are present in a wide range of organs and cells including central and peripheral nervous system. TRP channels were discovered in Drosophila photoreceptors, in a mutant that elicits a transient rather than maintained receptor potential in response to a sustained light stimulus. For this reason, this gene was termed transient receptor potential or trp. This mutation causes a ~10-fold reduction in the light induced Ca2+ influx to the photoreceptor (3, 6).Sociedad Argentina de Fisiología