Grafting of Embryonic Motoneurons into Spinal Cord and Striatum of Adult Mice

Abstract

The aim of the present work was to determine whether embryonic motoneurons could survive in the adult CNS and whether they display different survival and growth characteristics in their natural site (the spinal cord) as compared to an ectopic site (the striatal region of the brain). Specific labelling of embryonic motoneurons was obtained by retrograde transport of a fluorescent tracer (carbocyanine) followed by partial purification of the dissociated motoneurons on a density gradient. This technique offers the advantage that only the motoneurons in the cell suspension used for the grafts contain the fluorescent tracer. This study demonstrates that these motoneurons can survive and differentiate in the white and grey matters, not only in the adult spinal cord, but also in the brain. Furthermore, these motoneurons can migrate approximately 2 mm in the spinal cord and 4 mm in the brain.