Effect of serum-free medium on growth and differentiation of sympathetic neurons in culture.

Primary cultures of dissociated superior cervical ganglia (SCG) were grown either in serum-containing medium (+FBS) or in serum-free, defined medium (N1). The cultures were then compared for several differentiated properties. Neuronal survival was similar in the two media. Background cell, especially fibroblast, proliferation was less in N1. Small, intensely fluorescent cells were occasionally seen only in +FBS. Catecholamine fluorescence in neuronal processes and cholinergic synaptic activity persisted beyond 1 month in culture in both media. Quantitatively, however, neuritic outgrowth, nerve terminal fluorescence, and synaptic interaction were less in N1. Muscarinic depolarization and electrical membrane properties, including the presence of at least 4 voltage-sensitive outward currents, were similar in the two media. Thus, SCG neurons differentiate in N1 essentially to the same degree as they do in +FBS.