Quantity and Distribution of Proliferating Cells in the Juvenile and Adult Primate Spinal Cord

Abstract

Iultipotent progenitors exist in the adult mam- malian central nervous system, capable of producing both neurons and glia. Their proliferation in the spi- nal cord is limited. Generation of putative stem/pro- genitor cells has been reported in intact and injured spinal cord of rodents and in a limited number in monkeys with a spinal injury, but not in intact spi- nal cord in vivo. We recently reported de novo gener- ated cells in the intact spinal cord of macaque mon- keys. Here we extend these findings by showing data of intact juvenile and neonatal monkey spinal cord. We used bromodeoxyuridine (BrdU) to label the de novo generated cells in the experimental animals and stud- ied their quantity and distribution at different time- points after the BrdU infusion. As expected, we found a significant elevation of the BrdU-labeled cells at neo- natal stage. However, there was no difference between juvenile and adult stages. These results suggest that the survival of newly born cells in the intact primate spinal cord does not change after juvenile stage and this could be used to further study repair mechanisms in adult primate spinal cord.