IMMUNOCYTOCHEMICAL CHARACTERIZATION OF THE OLFACTORY RECEPTOR NEURONS OF THE BROWN TROUT (SALMO TRUTTA FARIO)

摘要

In fishes, olfactory sense is well developed and plays important roles in feeding, migration, and sexual behavior. The fish olfactory system comprises the olfactory organ and the olfactory bulbs. The olfactory organ of teleosts contains three major types of olfactory receptor neurons (ORNs): ciliated, microvillous and crypt cells. The teleost olfactory bulb is composed of four layers: olfactory nerve layer, glomerular layer, mitral cell layer, and granule cell layer. In trout, as in other teleosts, primary olfactory fibers reach the various glomerular fields, where they contact mitral cells, which in turn project to various telencephalic and extratelencephalic targets. Here, immunocytochemical techniques were used with the aim of characterizing theORNs in the brown trout olfactory organ and their projections.