Characterization of Neurotrophic and Neurotropic Interactions Between Neurons and their Muscle and Nerve Targets

摘要

Understanding the interactions between neurons and their denervated targets is critical to developing techniques to improve reinnervation of the denervated following nerve injury, and for attempting to facilitate regeneration in the central nervous system (CNS) where it does not occur. Experiments were designed to determine whether target-derived factors direct the outgrowth or regenerating axons and their own reinnervation. We have shown that neurite outgrowth from both sensory and motor neurons is directed up concentration gradients of target-derived factors both in vitro and in vivo. Using these gradients and the cells that secrete the factors we have succeeded in promoting regeneration across peripheral nerve gaps of up to 2 cm. Experiment are underway to bridge gaps of up to 8 cm. The target-derived factors that promote and direct axon regeneration, as well as determine the morphology of the processes are being characterized (more than 6 have been demonstrated). The presence of a peripheral nervous system regeneration inhibiting factor has been demonstrated and methods developed to block its influence. Experiments are underway to determine.