Nerve growth factor is a mitogen for cultured chromaffin cells

Abstract
Nerve growth factor (NGF) is essential for the survival and differentiation of a number of neural crest derivatives, including sympathetic and sensory neurones1–3. While early studies suggested that NGF might also have a mitogenic effect on these neurones4,5, subsequent work has favoured the interpretation that NGF promotes cell survival or differentiation rather than proliferation6,7. We have addressed the issue of a mitogenic effect of NGF using adrenal chromaffin cells, which are endocrine cells derived from the neural crest, and are closely related to sympathetic neurones. Adrenal chromaffin cells respond to NGF in vitro by expressing neuronal traits8–11. We now report that NGF elicits a mitotic response in cultured chromaffin cells from young rats, and that this response is blocked by an antiserum to 2.5S NGF. The chromaffin cells that divide in response to NGF can subsequently become neuronal in the continued presence of NGF.