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

针刺对弱视模型大鼠视皮层电活动水平的调节作用

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.

目的探究单眼形觉剥夺大鼠初级视觉皮层神经电活动的异常变化,观察敏感期针刺对大鼠视神经元电信号异常编码和传导的调控作用。方法将60只14日龄的Sprague-Dawley大鼠随机分为空白组、模型组、早期针刺组、中期针刺组和晚期针刺组,每组12只。在大鼠发育敏感期内(从睁眼到出生后第45天),除空白组外,其余各组大鼠均接受右眼睑缝合,建立单眼形觉剥夺模型。早、中、晚期针刺组分别于模型复制后第3天、第12天、第21天开始针刺治疗,每组接受9 d治疗。针刺治疗结束后采用神经电生理评估技术检测各组初级视觉皮层神经电信号的活动水平,包括P100波的潜伏期和波幅、神经元的平均放电频率和幅度、功率谱密度(PSD)和尖峰间期(ISI)。结果与空白组相比,形觉剥夺大鼠视觉中枢的P100波潜伏期明显延长,波幅明显降低(P<0.05);视觉皮层神经元的平均放电频率和幅度也明显降低(P<0.05);PSD降低,ISI明显延长(P<0.05)。与模型组相比,针刺治疗的三组大鼠视神经元的异常电活动改善,P100潜伏期缩短,波幅升高(P<0.05),放电频率和幅度明显增加(P<0.05),PSD降低,ISI缩短(P<0.05);针刺治疗的三组比较,早期针刺组各项指标改善效应最佳。结论形觉剥夺大鼠视觉中枢存在明显的电生理活动异常,大鼠视觉发育敏感期内针刺治疗可增强视神经细胞的生物电活动,提高视神经传导效率,调节形觉剥夺引起的视觉反应抑制和延迟。