Moyanova S, Kirov R, Ivanova V
Institute of Physiology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
Methods Find Exp Clin Pharmacol. 1997 Nov;19(9):605-11.
Changes in the spectral characteristics of the Fast Fourier Transformed (FFT) electroencephalogram (EEG) recorded from the frontal cortex of freely moving rats during quiet waking were studied after blockade of the 5-hydroxytryptamine-2 (5-HT2) receptors by the potent and long acting 5-HT2 antagonist ritanserin administered intraperitoneally (i.p.) at two doses (0.63 and 2.5 mg/kg). The rationale of this approach was to evaluate the subtle ritanserin-induced changes in the EEG in the frequency domain, and thus obtain more information about the neurophysiological effects mediated by brain 5-HT2 receptors and about the mechanisms underlying ritanserin's ability to increase sleep at the expense of wakefulness. Ritanserin induced significant changes in the power spectrum of EEG recorded from the frontal cortex. The activation index (the ratio of the dominant frequency in the power spectrum to the total power) significantly decreased after ritanserin, which was due to the increased EEG power in all frequency bands (except for beta 2) and to the decreased dominant frequency in the EEG spectrum, suggesting ritanserin-reduced EEG activation during quiet waking. The results favor the view of the excitatory modulating action of serotonin mediated via cortical 5-HT2 receptors and suggest that ritanserin could cause a faster transition from waking to sleep.
在自由活动大鼠安静清醒期间，从其额叶皮质记录的快速傅里叶变换（FFT）脑电图（EEG）的频谱特征变化，是在腹腔注射（i.p.）两种剂量（0.63和2.5mg/kg）的强效长效5-羟色胺-2（5-HT2）受体拮抗剂利坦色林阻断5-HT2受体后进行研究的。这种方法的基本原理是评估利坦色林在频域中对脑电图引起的细微变化，从而获得更多关于脑5-HT2受体介导的神经生理效应以及利坦色林以牺牲清醒为代价增加睡眠能力的潜在机制的信息。利坦色林引起额叶皮质记录的脑电图功率谱发生显著变化。利坦色林给药后，激活指数（功率谱中主频与总功率之比）显著降低，这是由于所有频段（除β2外）脑电图功率增加以及脑电图频谱中主频降低，表明利坦色林在安静清醒期间降低了脑电图激活。结果支持5-羟色胺通过皮质5-HT2受体介导的兴奋性调节作用的观点，并表明利坦色林可能导致从清醒到睡眠的更快转变。
