POLYAMINE NEUROTOXICITY IS ANTAGONIZED BY DIZOCILPINE IN CULTURED CHICK CORTICAL-NEURONS

Release of endogenous polyamines may contribute to neuronal loss in is chemia and related conditions. Primary cortical neurons were exposed t o spermine and spermidine and subsequently assayed for [H-3]ouabain bi nding to quantify neuronal loss. Neuronal survival was significantly d ecreased in the presence of spermine at 24 h (500 muM), 48 h (250 muM and 500 muM) and 72 h (10-500 muM) relative to controls. Co-applicatio n of 250 muM spermine and 10 muM dizocilpine for 48 h completely inhib ited the effect of spermine alone. Spermidine exposure (10-500 muM) di d not alter neuronal survival at any of the time points. These data in dicate that the polyamine spermine is toxic to neurons in vitro and th at toxicity is prevented by the NMDA-associated channel antagonist diz ocilpine.