抗うつ薬のVEPおよび脳波への急性効果

The acute effects of clomipramine hydrochloride (CMI), tricyclic antidepressant, were studied and compared with those of mianserin hydrochloride (MSR), tetracyclic antidepressant, by visual evoked potential (VEP), with each 16 and 12 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 subject. EEGs containing VEPs evoked by flash stimuli once every 5sec were derived from the two derivations (2ch : O1→ A1 + 2, 5ch : O1→Cz) and recorded into magnetic tape. Reproducing the tape, VEPs before and 120min after the administration of each drug, with 1024msec 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 VEP were studied and compared between these drugs. Individual VEPs 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, both latencies and peak-to-peak amplitudes of VEP did not significantly change. In EEG, the power% of α1 frequency band increased. These findings indicate that few effect of CMI on the visual system.
2. After the administration of MSR, latencies of short latency components (P3 and N3) significantly increased and peak-to-peak amplitudes of short latency components (P3-N3 and N3-P4) significantly decreased in VEP. In EEG, the power% of δ and θ frequency band increased, and that of α2 and β2 decreased. These findings indicate the inhibitory effect of MSR mainly on the lateral geniculate body and the optic radiation in the visual system.
3. From these results, it was considered that CMI has less effect on depression with anxiety or irritability than MSR.