Synaptophysin expression during in vitro neuronal differentiation. An immunocytochemical and a confocal laser microscopic study.

Primary neuronal cultures from mammalian fetal brains are widely used for morphological, biochemical and pharmacotoxicological studies. The usefulness of relatively pure neuronal cultures are now demonstrated for such studies. We have compared the neuronal survival and differentiation, the synaptophysin expression and the glial cell percentage in primary neuronal cultures using two different media: a M1 medium containing 10 % fetal calf serum and a M2 medium supplemented with hormones, ions and chemicals. Our study demonstrates that the M2 medium (a serum-free defined medium) is associated with an increased survival at 14 days of culture, an earlier neuronal differentiation and synaptophysin expression in cell bodies and neurites as it was confirmed by immunocytochemical and confocal laser microscopic studies.