Biological importance of the retrograde axonal transport of nerve growth factor in sensory neurons.

Abstract
Nerve growth factor is retrogradely transported in sympathetic and sensory neurons throughout life. Although this transport is biologically significant in sympathetic neurons, such a function was unknown in sensory ganglia. The neuropeptide substance P was used as a biochemical marker to show that sensory ganglia from newborn and adult rats respond to nerve growth factor and that its retrograde axonal transport is biologically relevant, as indicated by an increase in substance P and in general protein content.