摘要
目的探讨经颅直流电刺激(transcranial direct current stimulation,tDCS)对单眼剥夺(Monocular deprivation,MD)大鼠初级视皮层(V1)中CAMKⅡ、CREB和SYN1蛋白表达及视觉能力的影响,为弱视治疗提供理论基础。方法55只SPF级新生SD大鼠,从中选取43只于出生后14 d缝合右侧上下眼睑以建立单眼剥夺模型,单眼剥夺2周后选取36只缝合严密不漏光的大鼠随机分为模型组(MD)、阳极治疗组(anodaltDCS,a-tDCS)、假治疗组(shamtDCS,s-tDCS)。模型建立后进行为期14 d的tDCS治疗,对a-tDCS组每天施以1mA直流电刺激,每天1次,每次20 min;s-tDCS组只在刺激开始后1 min和结束前1 min给予电流刺激。视觉水迷宫用于测试视觉辨别能力和选择行为。图形视觉诱发电位(Pattern visual evoked potential,P-VEP)检测各组大鼠P100波振幅和潜伏期;HE染色观察V1中细胞形态和排列情况;Westernblot法检测V1中CaMKⅡ、CREB和SYN1蛋白表达水平;免疫组织化学染色观察SYN1阳性细胞数量。结果与Control组比较,MD组大鼠视觉辨别能力降低,选择正确率显著下降(P<0.0001);P100波振幅显著降低(P<0.001),潜伏期延长(P<0.001);V1中核仁皱缩,细胞排列不规整;CaMKⅡ、CREB和SYN1蛋白表达量下降(P<0.001);SYN1蛋白的平均阳性细胞数量减少(P<0.0001)。a-tDCS组与MD组相比,大鼠视觉辨别能力显著改善,选择正确率升高(P<0.0001);P100波振幅升高(P<0.001),潜伏期缩短(P<0.001);V1神经元排列规整,皱缩有所减少;CaMKⅡ、CREB和SYN1蛋白表达量显著升高(P<0.001);V1中SYN1蛋白的平均阳性细胞数量增加(P<0.05)。s-tDCS对MD组无治疗作用。结论a-tDCS可改善单眼剥夺大鼠的视觉能力,其机制可能与a-tDCS通过CaMKⅡ/CREB通路调节V1神经元突触可塑性有关。
Objective To investigate the effects of transcranial direct current stimulation(tDCS)on the protein expression of CaMKⅡ,CREB,and SYN1 and visual ability in the primary visual cortex(V1)of monocular deprivation(MD)rats,and to provide a theoretical basis for the treatment of amblyopia.Methods Forty-three out of fifty-five SPF-grade neonatal SD rats were selected to establish a monocular deprivation model by suturing the right upper and lower eyelids at 14 days after birth.After 2 weeks of monocular deprivation,36 rats with tight sutures and no light leakage were randomly divided into the model group(MD),the anodal treatment group(anodal tDCS,a-tDCS),and the sham treatment group(sham tDCS,s-tDCS).The tDCS treatment was carried out for 14 days after the model was established.A 1 mA direct current stimulation was applied to the a-tDCS group once a day for 20 minutes;the current stimulation was given to the s-tDCS group only 1 minute after the start of the stimulation and 1 minute before the end of the stimulation.The visual water maze was used to test visual discrimination and choice behavior.Pattern visual evoked potential(P-VEP)was used to detect the amplitude and latency of the P100 wave in each group of rats;HE staining was used to observe the morphology and arrangement of cells in V1;Western blot was used to detect the protein expression levels of CaMKⅡ,CREB,and SYN1 in V1;and immunohistochemical staining was used to observe the number of SYN1-positive cells.Results Compared with the control group,rats in the MD group showed reduced visual discrimination ability and a significant decrease in the correct selection rate(P<0.0001);a significant decrease in the amplitude of the P100 wave(P<0.001)and a prolongation of the latency period(P<0.001);crumpling of the nucleus pulposus and irregular arrangement of the cells in V1;and a decrease in the protein expression of CaMKⅡ,CREB,and SYN1(P<0.001).The average number of positive cells for SYN1 protein decreased(P<0.0001).The a-tDCS group showed significant improvement in the visual discrimination ability of rats compared with the MD group,and the rate of correct selection was elevated(P<0.0001);the amplitude of the P100 wave was elevated(P<0.001),and the latency period was shortened(P<0.001);V1 neurons were well aligned and there was a reduction in crumpling.The expression of CaMKⅡ,CREB,and SYN1 proteins was significantly elevated(P<0.001);the mean number of positive cells for SYN1 protein in V1 increased(P<0.05).The s-tDCS had no therapeutic effect on the MD group.Conclusions A-tDCS can improve visual ability in monocular deprived rats,and the mechanism may be related to the regulation of synaptic plasticity of V1 neurons by a-tDCS through the CaMKⅡ/CREB pathway.
作者
杨薛菲
胡晨莹
袁敦华
余博妍
纪阳斌
王继胜
丁见
Yang Xuefei;Hu Chenying;Yuan Dunhua;Yu Boyan;Ji Yangbin;Wang Jisheng;Ding Jian(School of Basic Medical Sciences,Wannan Medical College,Wuhu,Anhui 241002,China;School of Anesthesiology,Wannan Medical College,Wuhu,Anhui 241002,China)
出处
《齐齐哈尔医学院学报》
2025年第16期1508-1514,共7页
Journal of Qiqihar Medical University
基金
安徽省高校自然科学重点项目(2022AH051230)
安徽省中青年教师培养行动青年骨干教师境内访学研修资助项目(JNFX2023032)
安徽省大学生创新训练计划项目(S202310368026)
2024年度皖南医学院校级科研项目(WK2024ZZD10、WK2024XS13)。
