Neuronal growth factors and trophic
factors are signal molecules produced by neurons, glia, and target tissues that
can influence neuronal differentiation, growth of neurites, establishment of
contacts for signaling, maintenance of neural contacts with their central or
peripheral targets, and other functions.
These factors act through specific
receptors and can induce the production of specific molecules, such as agrin
for the maintenance of nicotinic cholinergic receptors at the neuromuscular
junction. Several identified growth factors, along with their sourced receptors
and possible roles, are provided in the table above.