Regulatory effect of acupuncture on electrical activity level of optic cortex in amblyopia model rats

Objective To explore the abnormal changes in neuroelectric activity in the primary visual cortex of rats deprived of vision in one eye and to investigate the regulatory effect of acupuncture in the sensitive period on the abnormal coding and conduction of electrical signals of rats’ optic neurons. Methods Sixty 14-day-old Sprague-Dawley rats were randomly divided into a blank group, a model group, an early-stage acupuncture group, a middle-stage acupuncture group, and a late-stage acupuncture group, with 12 rats in each group. Rats in every group except the blank group received right eyelid suturing to create a monocular deprivation model in the sensitive period of visual development (from the day rats open their eyes to the 45th day after their birth). Rats in the three acupuncture groups started to undergo acupuncture respectively on the 3rd, 12th, and 21st days after the model replication was done, with each group receiving nine-day treatment. The activity level of the neuroelectrical signal of the primary visual cortex in each group, including the latency and amplitude of P100 wave, average discharge frequency and amplitude of neurons, the power spectral density (PSD), and interspike interval (ISI), were measured by neuroelectric evaluation technology after the acupuncture treatment was finished. Results Compared with the blank group, the latency of P100 wave in the visual center of vision-deprived eyes was significantly prolonged, and the amplitude was significantly reduced ( P <0.05); the average discharge frequency and amplitude of the neurons in the visual cortex also decreased significantly ( P <0.05); PSD decreased and ISI was prolonged significantly ( P <0.05). Compared with the model group, the abnormal electrical activity of optic neurons in the three acupuncture groups ameliorated, the latency of P100 shortened, and the amplitude of P100 increased ( P <0.05), the discharge frequency and amplitude increased significantly ( P <0.05), the PSD reduced, and the ISI shortened ( P <0.05). In addition, among the three acupuncture groups, the early-stage acupuncture group had the best effect on various indicators. Conclusion Abnormal electrophysiological activity is significant in the visual center of vision-deprived rats, and acupuncture treatment in the sensitive period of visual development can enhance the bioelectrical activity of visual nerve cells, improve the efficiency of optic nerve conduction, and regulate the inhibition and retardation of visual response caused by visual deprivation.