ABSTRACT

During embryonic development, axons grow at high speeds by a process that appears to involve a pulling action exerted by a specialized structure at the leading edge, the growth cone. The present chapter will review briefly the mechanism of axon growth during development and compare this with what is known about the mechanism of axon elongation during regeneration in the central nervous system. Evidence in the lamprey suggests that these two processes may be very different and that regeneration may involve a protrusive force generated by neurofilament transport into the growing axon tip. If true, this could have important consequences for the use of axonal regeneration as a therapeutic strategy in treating injuries of the CNS.