The Differentiation of Non-Neuronal Elements in Neocortical Transplants
Brain tissue transplantation is a versatile technique with the potential to identify cellular mechanisms that control developing as well as mature functions of neurons and glia. We are currently interested in how the continued differentiation of embryonic donor tissue affects the ingrowth of adult host axons into these transplants. Two important variables are the type of host fiber and the age of the donor tissue at the time of transplantation. For example, axons labeled by acetylcholinesterase (AChE) histochemistry always start to grow into the transplants within a few days and ultimately achieve numerical densities comparable to the normal cortex (Hohmann and Ebner 1982, Park, et al. 1984). Monoamine fibers visualized by histofluorescence, in contrast, are not detectable for 3–4 weeks and never reach normal densities in these neocortical transplants (Park et al. 1984). Only rare thalamic and commissural fibers elongate across the interface zone into the transplants without special pretreatment (Smith et al. 1984). Host axons arising from peptidergic neurons have never been observed entering the transplants at any donor age (Ebner et al. 1984). Host GABAergic neurons grow into transplants taken from very young donors, embryonic day 14 or younger, but not at all into older donor tissue (Smith et al. 1984). All types of host fiber systems are damaged to some extent at the time of transplantation, but these results indicate that each responds to the damage in very different ways.
KeywordsMigration Tyrosine Germinal Neurol Fibril
Unable to display preview. Download preview PDF.
- Angevine, J.B., Sidman, R.L. (1962). Autoradiographic study of histogenesis in the cerebral cortex of the mouse. Anat. Ree. 142, 210.Google Scholar
- Berry, M., Maxwell, W.L., Logan, A., Mathewson, A., McConnell, P., Ashhurst, D.E., Thomas, G.H. (1983). Deposition of scar tissue in the central nervous system. Trauma 3, 31–53.Google Scholar
- Hohmann, C.F., Ebner, F.F. (1982). The development of cholinergic markers in normal and transplanted mouse neocortex. Neurosci. Abs. 8, 865.Google Scholar
- Hohmann, C.F., Ebner, F.F. (1985). Development of cholinergic markers in mouse forebrain. I. Acetylcholinesterase histochemistry and cholineacetyltransferase enzyme activity. Dev. Br. Res. In press.Google Scholar
- Liesi, P. (1984). The major matrix glycoproteins, laminin and fibronectin, in cultured cells from mammalian brain. In: Transplantation in the Mammalian CNS. Björklund, A., Stenevi, U. (eds.). p. 27.Google Scholar
- Morrison, R.S., de Vellis, J., Lee, Y. L., Bradshaw, R.A., Eng, L.F. (1984). Hormones and growth factors regulate the biosynthesis of glial fibrillary acidic protein in rat brain astrocytes. J. Cell Biol. In press.Google Scholar
- Park, J., Clinton, R.J., Ebner, F.F. (1984). The growth of catecholamine- and AChE- containing fibers into neocortical transplants. Neurosci. Abs. 10, 1083.Google Scholar
- Sharp, F.R., Gonzalez, M.F. (1984). Fetal frontal cortex transplant (14C) 2-deoxyglu- cose uptake and histology: Survival in cavities of host rat brain motor cortex. Neurol. 34, 1305–1311.Google Scholar
- Smith, L.M., Ebner, F.F. (1982). The fine structure of embryonic neocortex transplanted into adult mouse neocortex. Neurosci. Abs. 8, 865.Google Scholar
- Smith, L.M., Ebner, F.F. (1984). The expression of GFA protein synthesis in donor and host astrocytes following transplantation. Neurosci. Abs. 10, 983.Google Scholar
- Smith, L.M., Hohmann, C.F., Ebner, F.F. (1984). The development of specific cell types and connectivity in neocortical transplants. In: Transplantation in the Mammalian CNS. Björklund, A., Stenevi, U. (ed.). Amsterdam: Elsevier. In press.Google Scholar
- Woff, J.R. (1976). Quantitative analysis of topography and development of synapses in the visual cortex. Exp. Br. Res. Suppl. 1, 259–263.Google Scholar