Maturation of newly born vomeronasal neurons in the adult mice.

The olfactory and vomeronasal epithelia detect chemical stimuli in most tetrapods. Both epithelia undergo neural replacement during adulthood. In the central regions of vomeronasal epithelium, similar rates of neurogenesis and apoptosis evidence balanced replacement mechanisms. In the margins, the rate of neurogenesis is several times higher as compared with the rate of apoptosis suggesting net addition of neural receptor cells during adulthood. Herein, the fate of these marginal neuroblasts has been investigated in adult mice. Newly born and mature receptor neurons have been labeled. In the margins, more than 60% of new-born cells send axons to the accessory olfactory bulb. These results evidence that new neural elements from the vomeronasal epithelium are added to the accessory olfactory bulb preexisting circuitry.