GLUTAMINE IS INVOLVED IN THE DEPENDENCY OF BRAIN NEURON SURVIVAL ON CELL PLATING DENSITY IN CULTURE

THE mechanism by which neuronal cell viability in culture is dependent on cell plating density is unclear. To address this question, dissoci ated cells from the neonatal rat cortex were cultured in a chemically defined medium. Medium conditioned with cortical cells plated at high density (2000 cells/mm(2)) promoted the survival of neurons grown at l ow cell density (100 cells/mm(2)) in a dose-dependent manner. Data obt ained from molecular sieving suggested that the molecule(s) promoting the survival of neurons was smaller than 1000 Da. Amino acid analysis of the conditioned medium revealed the release of a mass of glutamine from cortical cells in culture. L-Glutamine mimicked the conditioned m edium in action promoting the viability of neurons. These findings sug gest that the effect of plating density on neuronal cell viability is mediated at least in part by glutamine released from cultured cells. N euroReport 9: 2353-2357 (C) 1998 Rapid Science Ltd.