Disclosed are methods and compositions for maintaining neural pathways
in a mammal including: enhancing survival of neurons at risk of dying; inducing
cellular repair of damaged neurons and neural pathways; stimulating neurons to
maintain their differentiated phenotype; and promoting dendritic outgrowth, including
maintaining dendritic arbors and regenerating dendritic architecture. In one embodiment,
the invention provides means for stimulating CAM expression in neurons. The invention
also provides means for evaluating the status of nerve tissue, including means
for detecting and monitoring neuropathies in a mammal. The methods, devices and
compositions include a morphogen or morphogen-stimulating agent provided to the
mammal in a therapeutically effective concentration. In another embodiment, the
invention provides methods and compositions which include a morphogen or morphogen-stimulating
agent, and a nerve trophic factor or nerve trophic factor-stimulating agent at
concentrations effective for stimulating dendrite outgrowth. The morphogen and
the nerve trophic factor can be admixed in combination.