Nerve growth factor regulates sympathetic ganglion cell morphology and survival in the adult mouse

Abstract

We have investigated the effects of prolonged systemic injections of nerve growth factor (NGF) and its antiserum on the survival and morphology of sympathetic ganglion cells in adult mice. Using intracellular injections of Lucifer yellow in lightly fixed superior cervical ganglia, we show that total dendritic lengths of ganglion cells are increased 29% after 2 weeks of NGF treatment. The increased dendritic length is characterized by increased branching within the dendritic arborization and not by the addition of new primary dendrites. In addition, cell soma cross-sectional area was increased 45%. Conversely, administration of NGF antiserum for 1 month decreased total dendritic length by 33%, decreased ganglion cell body size by 26%, and reduced the number of neurons in the ganglion by 25%. After 3 months of NGF antiserum treatment, the number of neurons in the ganglion was reduced a total of 41%. NGF antiserum treatment for 1 month in aged (22 months old) animals reduced ganglion cell body size by 21% and cell number by 22%, decreases that are comparable to those observed in young adult animals. Our results indicate that, even in maturity, sympathetic ganglion cells remain dependent on NGF for survival and maintenance of dendritic geometry, and this dependence continues into old age.

Nerve Growth Factor and Nociception: From Experimental Embryology to New Analgesic Therapy

“…Initially, efforts focused on identifying precisely which neuronal populations depend on NGF for survival and when. It is through such experiments and later genetics that we know that NGF is required for the survival of sympathetic ganglion neurons and a large proportion of embryonic sensory neurons that are destined to become nociceptors (Ruit et al, 1990(Ruit et al, , 1992Crowley et al, 1994). It appears that both sympathetic and sensory neurons largely lose their absolute dependency on NGF for survival in the post-natal period (Ruit et al, 1990(Ruit et al, , 1992).…”

Neurotrophins: key regulators of cell fate and cell shape in the vertebrate nervous system

“…5). In adult rats, not only does the administration of NGF cause dendritic length to increase but, also, the administration of NGF-antibodies decreases it (Ruit et al 1990). Interestingly, the increased number of dendrites induced by NGF is accompanied by a very large increase in the number of preganglionic axons innervating NGF-responsive ganglia (Schafer et al 1983).…”

“…Neurotrophins modify the shape of neurons. (Top) Sympathetic neurons of the adult rat superior cervical ganglion were filled with a fluorescent dye, and the morphology of cell bodies, dendrites, and axons (asterisk) was monitored in control, NGFtreated, or NGF antibody-treated animals (Ruit et al 1990; Fig. 2).…”

Regulation of NGF and NT-3 protein expression in peripheral targets by sympathetic input

“…In the periphery, NGF and NT-3 are produced by target tissues, internalized by the innervating sympathetic and/or sensory neuron, and retrogradely transported to the cell body (Thoenen and Barde 1980;Schwab et al 1982;Zhou and Rush 1996;Zhou et al 1997;Kuruvilla et al 2004), where they carry out their survival activities. NGF is essential for the survival of sympathetic neurons during development (Gorin and Johnson 1980;Crowley et al 1994) as well as in adulthood (Ruit et al 1990;Ghasemlou et al 2004). NT-3 also is important for the survival of sympathetic neurons (Zhou and Rush 1995;Rush et al 1997;Francis et al 1999).…”