APPEARANCE OF DETERIORATED NEURONS ON REGIONALLY DIFFERENT TIME TABLES IN RAT-BRAIN THIN SLICES MAINTAINED IN PHYSIOLOGICAL CONDITION

Brain slices are widely used for electrophysiological experiments. However, the time table of the chronological cell deterioration and its regional difference in slices are unknown. The argyrophil III staining method can demonstrate deteriorated ('collapsed') neurons specifically. Therefore we studied the appearance of the 'collapsed' neurons with time in coronal brain 'thin' slices maintained in vitro to evaluate possible regional differences in vulnerability In the hippocampus, CA1 pyramidal, dentate gyrus granule, and nonpyramidal cells in any subfield became argyrophilic most easily, as did layer V-VI pyramidal neurons in the neocortex. These results suggest that some subclasses of neurons in brain slices degrade earlier than others even when maintained in physiological condition.