Instant sedative effect of acupuncture at GV20 on the frequency of electroencephalogram α and β waves in a model of sleep deprivation.

Sleep deprivation (SD) adversely affects brain function and is accompanied by frequency-dependent changes in electroencephalograms (EEGs). Recent studies have suggested that acupuncture is an emerging alternative therapy for SD. However, the involvement of the frequency of EEG α and β waves in the protective effect of acupuncture against SD remains unknown. The present study investigated the instant effect of acupuncture at GV20 on insomnia by analyzing the frequency of α and β waves using electroencephalography in a model of sleep deprivation. A total of 16 rats (Wistar; male; weight, 340±10 g) were divided randomly into four groups (4 rats per group) to create a rat model of sleep deprivation using the modified multiple platform method in the GV20 group, the sham acupoint group and the model group. After 72 h of sleep deprivation for these three groups and normal feeding for the blank group, the EEG data of all four groups were documented. Following the initial measurement, the GV20 group was treated by acupuncture at GV20 and the sham acupoint group was treated at the sham acupoint, and their EEGs were recorded during the treatment. The frequency of α and β waves of all EEG data were analyzed. Prior to intervention, the GV20 group, the sham acupoint group and the model group exhibited no significant differences in α and β wave frequencies; however, the α wave frequency of these three groups was significantly decreased compared with the blank group (P<0.05), whereas the β wave frequency of these three groups was significantly increased compared with the blank group (P<0.05). This suggested that sleep deprivation affected the frequency of brain waves and enhanced the excitability of the cerebral cortex. During acupuncture treatment with retained needle conditioning, the GV20 group indicated a significant increase in α wave frequency (P<0.05), as well as a significant decrease in β wave frequency compared with prior to treatment (P<0.05), whereas the sham acupoint group exhibited no significant changes. The present findings from a rat model of sleep deprivation suggested that acupuncture treatment at GV20 may reduce the excitability of the brain cortex. Due to its sedative effect, treatment at GV20 may be considered for the treatment of insomnia and related symptoms.