Nerve growth factor regulates the action potential duration of mature sensory neurons

The effect of nerve growth factor (NGF) on the action potential of sensory ganglion neurons was investigated in long-term organotypic cultures of embryonic mouse dorsal root ganglia grown isolated or attached to spinal cord explants. The present study demonstrates that NGF regulates a specific bioelectric property of these neurons--the duration of the Ca2+ component of the somatic action potential--at mature stages when they no longer require NGF for survival. Prolonged culture of fetal mouse dorsal root ganglion neurons with relatively low levels of NGF shortens the duration of the action potential. Furthermore, addition or withdrawal of NGF in mature cultures results, within several days, in shorter or longer action potential durations, respectively. Exposure to anti-NGF antiserum accelerates the onset of the longer-lasting action potentials elicited by simple withdrawal of NGF. This plastic response of sensory neurons to NGF may be important in regulating their physiological properties and/or their response to injury.