The acute effects of clomipramine hydrochloride (CMI) and mianserin hydrochloride (MSR) on somatosensory evoked potential (SEP) were studied with each 12 and 16 healthy male subjects, respectively. In the two experimental sessions, CMI (0.5mg/kg) or MSR (0.3mg/ kg) was orally administered for each subject. EEGs containing SEPs evoked by electric stimuli, once every 5 sec, were derived from the two derivations (monopolar : C3'→A1+2, bipolar : C3'→F3'), and recorded into magnetic tape. Reproducing the tape, SEPs 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 SEP were studied. Individual SEPs were subjected to the component analysis, and to the statistical assessment together with EEG. The following, statistically significant (P<0.01, P<0.05), results were obtained.
1. After the administration of CMI, the latencies were significantly decreased for the early middle latency component (P2 and N2), and significantly increased for the long latency component (monopolar : P6~, bipolar : P7~). While those of late middle latency component (P4~P5) did not change significantly. The amplitudes of middle latency component (P3 and P4) increased significantly. In EEG, the power % were significantly increased for α1. In conclusion, stimulatory properties of CMI was verified by SEP.
2. After the administration of MSR, the latencies were significantly increased for the almost all middle and long latency component. The amplitudes of middle and long latency components (N4, P5 and P6) decreased significantly. In EEG, the power % were significantly increased for δ and θ, and significantly decreased for α2 and β2. In conclusion, sedative properties of MSR was verified by SEP
