睡眠紡錘波の出現異常に関する実験的検討 : 尾状核・視床熱凝固による紡錘波ノミーストの変化

Abstract

Although many clinical investigations of sleep spindles have been discussed, the mechanisms of spindle activity still remain unclear. Cortical barbiturate spindle bursts (7-14 Hz) in anesthetized cats before and after thermocoagulation were studied in duration (SDV : sec), appearance (SAV : /min), and latency (SLV:sec). Normal control spindle bursts (number of subjects, 34 ; number of spindles in the left, 363 ; in the right, 358) showed as follows : SDVs were 1.45±0.45 sec (mean±SD) in the left and 1.49±0.47 sec in the right;SAVs were 11.5/min in the left and 11.4/min in the right;and SLV was 0.36±0.45 sec. These data suggested spindle activities were statistically symmet- rical and consistent. Stereotactic thermocoagulated lesions in the caudate nucleus (C group : n=7) altered spindle duration bilaterally. SDVs after thermocoagulation in both hemispheres were significantly longer than those before coagulation (p＜0.01). SAVs and SLVs remained unchanged after thermocoagulation in C group. Thermocoagulation in the lateral thalamus (L group : n=8) altered spindle appearance and duration, but the medial thalamic lesions (M group: n=7) did not affect spindle activity. These results showed the close electrophysiological relationships in spindle activities between the thalamus and the caudate nucleus. In conclusion, the caudate nucleus plays an important role in regulating bilateral spindle duration and the lateral thalamus may affect spindle appearance and duration via pulvinar or caudate nucleus.