CORTICOSTERONE ATTENUATES ZINC-INDUCED NEUROTOXICITY IN PRIMARY HIPPOCAMPAL CULTURES

Primary hippocampal cultures derived from newborn rats were exposed to zinc chloride at 50, 75, 100, 150 and 200 mu M concentrations, Neuron al injury was assessed morphologically and by the lactate dehydrogenas e (LDH) efflux assay. Zinc exposure increased LDH efflux in a concentr ation-dependent manner. Exposure to 100 mu M zinc for 24 h resulted in beading of neurites and swelling of neuronal soma. When cultures were co-exposed to zinc at 100 mu M and corticosterone in the range of 10( -5) to 10(-7) M, degeneration of neurons caused by zinc was attenuated . Our study suggests that corticosterone can protect neurons from zinc -induced neurotoxicity at low doses. (C) 1998 Elsevier Science B.V.