Journal of Neuroscience, Vol 3, 2448-2462, Copyright © 1983 by Society for Neuroscience
Properties of neurons from dissociated fetal rat brain in serum-free culture
Z Ahmed, PS Walker and RE Fellows
Because of the unknown constituents and varying composition of serum, its
presence in media used in cell culture unavoidably compromises attempts to
study cellular mechanisms of growth and differentiation. To overcome this,
we have devised a serum-free, chemically defined medium which maintains
primary cultures of fetal rat brain cells for more than 6 weeks. This
medium allows expression of characteristic properties of neurons and
prevents overgrowth of non-neuronal elements without use of antimitotic
agents. Cells prepared and plated without exposure to serum attach in less
than 20 min to poly-D-lysine substratum and begin to extend processes
within 1 hr. After 2 days in culture, process-bearing cells can be divided
into those with characteristic neuronal morphology, including long
processes which generally branch at a distance from the perikaryon, and
those having the appearance of glial cells with many short, thin processes
which branch frequently near the cell body. The remaining non-neuronal
cells are large and flat with few or no processes. The presence of neurons
and astroglia was demonstrated by immunofluorescence detection of bound
tetanus toxin as a neuron- specific surface marker, and glial fibrillary
acidic protein as an astroglial marker. By the 3rd day in culture, many
cells of neuronal morphology were able to generate action potentials in
response to electrical stimulation. The ionic composition of the inward
current changes from Ca2+ to predominantly Na+ by about 10 days in culture.
The presence of synaptic vesicles and myelin was demonstrated by electron
microscopy. The ability of dissociated cells from mammalian brain to grow
in defined medium without serum and acquire selected properties of mature
cells in vivo demonstrates the potential of this culture system for
neurobiological studies at the cellular level.