GLIA-DEPENDENT NEUROTOXICITY AND NEUROPROTECTION IN MESENCEPHALIC CULTURES

Dopaminergic neurotoxicities of 6-hydroxydopamine (6-OHDA) and the lip opolysaccharide (LPS) were compared in rat mesencephalic cultures plat ed on poly-L-lysine or on glial monolayers. In the neuron-enriched cul tures plated on polylysine, 6-OHDA killed 89% Of the tyrosine hydroxyl ase (TH)-immunopositive neurons, but LPS was not neurotoxic. Conversel y, in mixed neuron/glial cultures, 6-OHDA killed only 27% of the TH-im munopositive neurons while LPS killed 70%. The mixed neuronal/glial me sencephalic culture offers a better in vitro model for studying possib le mechanisms involved in Parkinson's disease.