Podol'skiĭ I Ia, Vorob'ev V V, Belova N A
Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences.
Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Nov-Dec;50(6):982-90.
Statistical analysis of EEG spectra averaged over 10-min periods showed that inhibitor of acetylcholinesterase physostigmine induced the long-term (tens of minutes) characteristic changes in the electric activity of the dorsal hippocampus (CA1 field) and somatosensory cortex of unrestrained rats. With increasing the physostigmine dose from 0.05 to 0.5 or 1 mg/kg the averaged power of the theta-rhythm did not rise in the range of 3.6-4.9 Hz and was suppressed in the range of 5.7-11.9 Hz both in the hippocampus and neocortex. The maximal frequency shifted to the left (from 3.6-6.4 to 3.6-4.9 Hz). In contrast to this, the averaged power in the delta (1-1.5 Hz)-I and beta-2 ranges (20.3-26.5 Hz) significantly nonlinearly increased and that of the beta-1 substantially decreased. Scopolamine eliminated all extrema of the hippocampal and neocortical EEG spectra induced by physostigmine, which is indicative of the role of M-cholinoreceptors in these effects. The increased dose of physostigmine (1 mg/kg) produced inversion of the ratio between the averaged power of beta-2 in neocortex and hippocampus: it became significantly higher than in the neocortex. All these data suggest that the mechanisms of cholinergic modulation of the theta- and beta-rhythms are essentially different. We think that significant enhancement of the content of endogenous acetylcholine content produce a long-term tonic decay of the functional activity of the hippocampus and neocortex and play an important role in the mechanisms of dissociated states of memory and consciousness, contextual learning and conditioned switching.
对10分钟时段内平均的脑电图谱进行统计分析表明，乙酰胆碱酯酶抑制剂毒扁豆碱可引起未受束缚大鼠背侧海马体（CA1区）和体感皮层电活动的长期（数十分钟）特征性变化。随着毒扁豆碱剂量从0.05增加到0.5或1毫克/千克，海马体和新皮层中3.6 - 4.9赫兹范围内的θ节律平均功率未升高，而在5.7 - 11.9赫兹范围内被抑制。最大频率向左移动（从3.6 - 6.4赫兹移至3.6 - 4.9赫兹）。与此相反，δ波（1 - 1.5赫兹）-I和β-2波段（20.3 - 26.5赫兹）的平均功率显著非线性增加，而β-1的平均功率大幅下降。东莨菪碱消除了毒扁豆碱诱导的海马体和新皮层脑电图谱的所有极值，这表明M胆碱受体在这些效应中起作用。毒扁豆碱剂量增加（1毫克/千克）导致新皮层和海马体中β-2平均功率比值发生反转：海马体中的比值变得显著高于新皮层。所有这些数据表明，胆碱能对θ和β节律的调制机制本质上是不同的。我们认为内源性乙酰胆碱含量的显著增加会导致海马体和新皮层功能活动的长期强直性衰退，并在记忆和意识的解离状态、情境学习和条件转换机制中起重要作用。
