Transplantation of postnatal vomeronasal organ in the CNS of newborn rats.

The present study was conducted to examine the survival and development of intracerebral transplanted neonatal rat vomeronasal organs (VNs). Complete neonatal (P5-P10) VNs were transplanted into the parietal cortex region of littermates and examined at 10-100 days by light microscopy. The VN survived and was organized into a series of vesicles lined by respiratory and/or sensory epithelia. Sensory neurons grew long axons that fasciculated and invaded the surrounding brain parenchyma. The newly developed axons did not prefer a specific brain region. The axons developed a complex fiber plexus either at the interface between transplant and host tissue or deep within the host brain parenchyma. Vomeronasal axons consistently formed glomerular-like structures within the fiber plexus. Our results suggest that glomerular formation is not dependent on specific target of length of axon development, but rather on a set of complementary axons that display mutual recognition.