A. Left panel shows representative trace of mEPSCs recorded from a juvenile mouse treated with vehicle as a neonate. Right panel displays representative trace of mEPSCs recorded from a mouse treated with ketamine as a neonate. Asterisks mark mEPSCs. B. Mice treated with ketamine as neonates (n = 9 mice, n = 19 neurons) had significantly increased frequency of mEPSCs in CA3 neurons compared to those treated with vehicle (n = 8 mice, n = 22 neurons) (left panel) and a significant leftward shift in the cumulative frequency of the interevent interval (right panel). C. There was no change in the average amplitudes of mEPSCs between groups (left panel), but there was a significant rightward shift in cumulative frequency of mEPSC amplitude (right panel). D. Neonatal ketamine also significantly shortened rise time of mEPSC events compared to vehicle. E. There was no change in decay of mEPSCs between groups.
mEPSC, miniature excitatory postsynaptic current; PND, postnatal day.