Ciliary neurotrophic factor (CNTF) has a dose-dependent biphasic effect on the number of adrenergic cells which develop in avian trunk neural crest cultures.

The embryonic neural crest is the source of progenitor cells for a wide variety of adult cell types including several populations of neurons and neuroendocrine cells. We have investigated the effect of ciliary neurotrophic factor (CNTF) on the development of quail trunk neural crest cultures. We found that at low doses CNTF promoted the development of increased numbers of adrenergic cells, but higher doses resulted in a decreased number of adrenergic cells relative to controls. Total and melanocyte cell number were unaffected over the range of CNTF concentrations tested. These results indicate that CNTF can affect adrenergic development in neural crest cultures in a dose-dependent biphasic manner.