Trophic factors play an important role in the
development of neurons and glia. In order to
study the involvement of neurotrophins in
human cortical development, human fetal
parietal cortical tissue, obtained after early
elective abortions, was transplanted to cortical
cavities in immunosuppressed rats. Using in situ
hybridization it was demonstrated that nerve
growth factor, brain-derived neurotrophic factor
and neurotrophin-3 mRNAs are expressed in
developing human cortical xenografts. We conclude
that neurotrophins may play a role in
human cortical development and rat-derived
astroglial cells could be involved in establishing
reciprocal “permissive sites”