Segregated populations of mitral/tufted cells in the accessory olfactory bulb

THE dendritic distribution of mitral/tufted (M/T) cells in the opossum accessory olfactory bulb (AOB) was investigated using intracellular injection of Lucifer yellow and DiI labeling. Lucifer yellow labeling demonstrated that the primary dendrites of M/T cells are restricted to one of the two subregions (anterior or posterior) of the glomerular layer. When DiI was placed in the anterior or posterior subregion of the glomerular layer, virtually all of the labeled cell bodies in the AOB were located in the anterior or posterior part of the M/T cell layer, respectively. These results demonstrate that the anterior and posterior subregions of the AOB glomerular layer are termination sites for dendrites belonging to distinct populations of M/T cells.