Effects of glia-conditioned medium on primary cultures of central neurons.

The effects of glia conditioned media on the survival and differentiation of embryonic neuron cultures of the Central Nervous System is described. We established glial cultures of peritumoral areas and the culture medium was changed serially and collected as glia conditioned medium (GCM). Neuron enriched cultures plated on poly-L-lysine coated Petri dishes and after 4 days in vitro, the neuronal cultures were treated for the inhibition of glial cells. We established two groups of neuronal cultures that were respectively exposed to the GCM and to conventional culture medium. We evaluated the survival and differentiation of neuronal population in each group of cultures by contrast-phase microscopy and cellular uptake of Horse Radish Peroxidase. The cell cultures exposed to GCM showed a survival during the in vitro stages and an organization and differentiation pattern of mature neurons larger than the control cultures. This fact suggests that the glial cultures produce a diffusible neurotrophic factor that influences the neuronal response in vitro.