Motoneurons were plated on poly-ornithine/laminin- treated wells in the presence (or not when mentioned) of a cocktail of neurotrophic factors (0.1 ng/ml glial-derived neurotrophic factor (GDNF), 1 ng/ml brain-derived neurotrophic factor (BDNF) and 10 ng/ml ciliary neurotrophic factor (CNTF)...