FIGURE 4.

Hippocampal GABAergic transmission during adulthood remains unchanged after chronic late Adolescence ketamine treatment. (A) Schematic arrangement of electrophysiological recordings in the pyramidal layer of CA1 area of vHPC (upper). Samples traces of sIPSC (left) and mIPSC (right) from Veh and Ket slices (lower). (B) Slices recordings from Ket rats did not show a change of the sIPSC frequency compared to Veh treatment (left). On the other hand, the sIPSC amplitude values were not different between groups (right) (t-test, p > 0.05). (C) Frequency of mIPSC from the Ket group was not significant different compared to the Veh group (left). The mIPSC amplitude was also unchanged after treatment (right) (t-test, p > 0.05). (D) Sample traces of evoked IPSC amplitudes as a function of stimulus intensity plotted as input/output curves in inhibitory synapses (left). Input/output curves revealed that eIPSC amplitudes at all stimulus intensities did not differ between groups (Repeated measures ANOVA/Bonferroni post hoc test, p > 0.05). (E) Paired-pulse responses superimposed after subtraction of the first pulse at 30, 70, 100, and 300 ms ISIs (left). Ket-treated rats did not change paired pulse ratio compared to the Veh group (Repeated measures ANOVA/Bonferroni post hoc test, p > 0.05). (F) Sample traces of synaptic responses evoked by a burst of 20 stimuli at 10 Hz (left). Depression induced by repetitive stimulation remained unchanged in slices from Ket rats compared to the Veh-treated group (right) (Repeated measures ANOVA/Bonferroni post hoc test, p > 0.05). Data are the mean ± SEM. Number of animals is indicated in parentheses or within bars. ^∗p > 0.05, ^∗∗p > 0.001, and ^∗∗∗p > 0.0001.