Continual replacement of newly-generated olfactory neurons in adult rats

It has been known that stem cells do exist in the central nervous system, a nd adult neurogenesis is continually taking place in the olfactory bulb dur ing life. We report here, with the combined method of autoradiography using H-3-thymidine and immunohistochemistry for a neuronal marker, that 65.3-76 .9% of calretinin-immunoreactive bulbar neurons are replaced during the sho rt period of 6 weeks in the adult rodent. The results indicate that neurona l replacement is a common phenomenon in the olfactory bulb during life. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.