Journal of Neuroscience, Vol 7, 1595-1600, Copyright © 1987 by Society for Neuroscience
Interactions between growth cones and neurites growing from different neural tissues in culture
JP Kapfhammer and JA Raper
We have previously used retinal and sympathetic explants to show that
growth cones recognize and retract from specific neurites in culture
(Kapfhammer et al., 1986). In an effort to determine the generality of this
phenomenon and to see how many different neurite labels can be detected by
it, we have studied interactions between individual growth cones and
neurites extending from a variety of neural sources in vitro. Using most of
the possible pairings between sympathetic, ciliary, dorsal root ganglion
(DRG), retinal, and diencephalic neurons, we have found that in most
instances: (1) Growth cones do not retract from neurites originating from
the same tissue; (2) retinal growth cones do not retract from diencephalic
neurites; (3) sympathetic, ciliary, and DRG growth cones, with one possible
exception, do not retract from sympathetic, ciliary, or DRG neurites; (4)
retinal growth cones retract from sympathetic, ciliary, and DRG neurites;
(5) sympathetic, ciliary, and DRG growth cones retract from retinal
neurites; and (6) sympathetic growth cones retract from diencephalic
neurites. A simple hypothesis consistent with these results is that 2
labels exist--one associated with central neurites and another associated
with peripheral neurites-- and that peripheral growth cones are programmed
to retract from the central label and central growth cones are programmed
to retract from sympathetic, ciliary, and DRG neurites; (5) symevant to the
separation of the CNS and PNS during development.