The acute effects of antidepressants on the human AEP (Auditory Evoked Potential) and EEG

The acute effect of clomipramine hydrochloride (CMI) was studied by auditory evoked potential (AEP) and compared with those of mianserin hydrochloride (MSR), with each 12 and 16 healthy male subjects, respectively. In the two experimental session on different days, CMI (0.5mg/kg) or MSR (0.3mg/kg) were orally administered for each subjects. EEGs containing AEPs evoked by click stimuli once every 5 sec were derived from the two derivations ( 3ch : Cz→A1+2 , 6ch : Cz→T5) and recorded into magnetic tape. Reproducing the tape, AEPs before and 120 min after the administration of these drugs, with 1024 msec of analysis time were obtained by averaging 100 responses, and EEGs were subjected to the frequency analysis. The changes of the waveform of group mean AEP were studied. Individual AEPs were subjected to the component analysis, and to the statistical assessment together with EEG. The following, statistically significant results were obtained. 1. After the administration of CMI, only P8 and N8 latencies of long latency components significantly increased (P<0.05), while the peak-to-peak amplitudes of middle latency components significantly increased (P<0.01, P<0.05). In EEG, the α1 power% significantly increased (P<0.01). In conclusion, stimulatory effect of CMI besides inhibitory effect was verified by AEP. 2. After the administration of MSR, P2 and P3 latencies of the middle latency components and those of long latency components (P7~) significantly increased (P<0.01, P<0 05). All of significant changes were decrease for the peak-to-peak amplitudes (P<0.01, P<0.05). In EEG, the power% were significantly increased for δ and θ, but significantly decreased for α2 and β2 (P<0.01, P