In P11 animals (A), pretreatment with bumetanide prevented kindling-induced decrease of afterdischarge threshold (ADT), increase of afterdischarge duration (ADD), and limited seizure response to threshold stimulation to a maximum of stage 2 seizures. Both P14 (B) and P21 (C) animals, exhibited significant decrease of ADT, increase of ADD, as compared with pre-kindling values, and developed up to stage 4 seizures in response to threshold stimulation. On A-C data are presented as Mean±SEM; asterisks on A-C- p<0.05 vs. respective values before kindling (paired t-test); dagger on A- p<0.05 vs. Control (Mann-Whitney test). D: Plot of ADT after kindling in individual animals of three ages. For each animal, the effect of bumetanide is expressed as percent of ADT before kindling and bumetanide injection (Y-axis). Color-coded numbers under the X-axis correspond to respective data points for each animal and age. Arrows point to those subjects in which ADT was within pre-kindling Mean ± 2 standard deviations.