CELL VIABILITY AND LAMININ-INDUCED NEURITE OUTGROWTH IN CULTURES OF EMBRYONIC CHICK NEURAL-TUBE CELLS - EFFECTS OF CYTOSINE-B-D-ARABINOFURANOSIDE

We have measured the effects of cytosine-beta-D-arabinofuranoside (Ara C) on cell survival and neurite outgrowth in cultures of dissociated 4 -6 day embryonic chick neural tube cells. High con centrations of AraC (greater than 100 mu M) reduced neuronal eel survival and neurite out growth from viable cells. Concentrations normally used to inhibit mito tic cell division (1-10 mu M) were toxic to the neurones cultured in s erum free medium on a poly-DL-ornithine/laminin substrate. AraC does n ot appear to have a neurite promoting effect on dissociated neurones t hat are cultured in the presence of low numbers of non-neuronal cells. This suggests that the neurite promoting effects of AraC reported by others is likely to be through the non-neuronal cells that were an inh erent feature of the culturing systems in these studies. AraC cytotoxi city was completely blocked by the addition of the competitive antagon ist: 2'deoxycytidine (2'DC) but not by its metabolic precursor cytosin e (cyt). We suggest that the acute effects of AraC on neurones which a re actively growing neurites are the result of interference with lipid metabolism.