PT  - JOURNAL ARTICLE
AU  - EW Godfrey
AU  - EM Shooter
TI  - Nerve growth factor receptors on chick embryo sympathetic ganglion cells: binding characteristics and development
AID  - 10.1523/JNEUROSCI.06-09-02543.1986
DP  - 1986 Sep 01
TA  - The Journal of Neuroscience
PG  - 2543--2550
VI  - 6
IP  - 9
4099  - http://www.jneurosci.org/content/6/9/2543.short
4100  - http://www.jneurosci.org/content/6/9/2543.full
SO  - J. Neurosci.1986 Sep 01; 6
AB  - NGF is essential for the development and maintenance of sympathetic and certain sensory neurons. The NGF receptors on the surface of sympathetic ganglion cells from chick embryos were characterized; they consist of high-affinity receptors with a dissociation constant of about 10(-11) M, and low-affinity receptors with a dissociation constant of about 10(-9) M. There are more than 10 times as many low- affinity as high-affinity receptors per cell. The heterogeneity of NGF binding is not due to negatively cooperative interactions among the receptors. The high- and low-affinity components of NGF binding defined at steady state correspond to slowly and rapidly dissociating components of bound NGF seen in kinetic experiments. In addition, a very slowly dissociating component of bound NGF was observed; this component was a small fraction of binding at low concentrations of NGF but increased to 20–60% of bound NGF at the highest NGF concentrations examined. This very slowly dissociating component of bound NGF accounts for several peculiarities in the binding data not accounted for by steady-state binding of NGF to its high- and low-affinity receptors. Developmental studies showed that both high- and low-affinity NGF receptors were present on chick embryo sympathetic ganglion cells from 6.5 to 20 d in ovo. No significant differences in the numbers or affinities of the receptors were seen with cells from ganglia at 9, 11, or 15 d of development. Cultured non-neuronal cells from sympathetic ganglia had only low-affinity NGF receptors.