电针对透镜诱导型近视豚鼠脉络膜血流和内皮素-1及其受体表达的影响

Effect of electroacupuncture on choroidal blood flow and the expression of endothelin-1 and its receptor in lens-induced myopic guinea pigs

目的:观察透镜诱导型近视豚鼠脉络膜毛细血管密度的变化,探讨脉络膜内皮素-1(ET-1)、内皮素受体A(ETAR)及受体B(ETBR)的表达变化及电针治疗机制。方法:将54只豚鼠随机分为正常对照组(NC组)、透镜诱导组(LIM组)和电针+透镜诱导组(LIM+EA组)。NC组正常饲养,不干预;LIM组和LIM+EA组右眼配戴-6.00D透镜片,建立近视模型。造模2、4wk测量各组豚鼠屈光度、眼轴和脉络膜毛细血管密度,实时荧光定量PCR(q-PCR)、酶联免疫吸附试验(ELISA)和免疫组化检测各组脉络膜ET-1、ETAR和ETBR mRNA及蛋白表达水平。结果:造模2、4wk后,与NC组相比,LIM组和LIM+EA组近视屈光度和眼轴均增加(均P<0.001);LIM+EA组与LIM组相比,屈光度和眼轴均减小(均P<0.05)。造模2、4wk后,与NC组相比,LIM组脉络膜毛细血管密度均降低(P<0.001),脉络膜ET-1、ETAR及ETBR mRNA和蛋白水平均增加(均P<0.05);而LIM+EA组与LIM组相比,脉络膜毛细血管密度升高(P<0.01),脉络膜ET-1、ETAR及ETBR mRNA和蛋白水平均降低。结论:在透镜诱导型近视豚鼠中,随着屈光度和眼轴的增长脉络膜血流减少,而电针可能通过神经调控改善了脉络膜的血流,影响了血管剪切力,下调ET-1及其受体含量以延缓近视的发生发展。

AIM:To observe the changes of the vessel density of choriocapillaris in lens-induced myopia in guinea pigs,and to explore choroidal endothelin-1(ET-1),endothelin receptor A(ETAR)and receptor B(ETBR)expression changes and the effect of electroacupuncture.METHODS:Fifty-four guinea pigs were randomly divided into normal control(NC),lens-induced myopia(LIM)and LIM+electroacupuncture(LIM+EA).The NC group was fed normally without intervention and the right eye in LIM group and LIM+EA group was coverd with a-6.00D lens to establish a myopia model.At 2 and 4wk,the refraction,axial length and the vessel density of choriocapillaris in groups were measured.The expression and protein content of ET-1,ETAR and ETBR mRNA in groups were detected by the real-time fluorescent quantitative PCR(quantitative polymerase chain reaction,q-PCR),enzyme-linked immunosorbent assay(ELISA)and immunohistochemistry.RESULTS:At 2 and 4wk,compared with the the NC group,refraction and axial length in LIM group and LIM+EA group had significantly increased(all P<0.001).Compared with the LIM group,the refraction and axial length in LIM+EA group were decreased(all P<0.05).At 2 and 4wk,compared with the NC group,the vessel density of choriocapillaris was decreased(P<0.001)and the ET-1,ETAR and ETBR mRNA and protein levels in choroid were increased(all P<0.05)in LIM group.At 2 and 4wk,compared with the LIM group,the vessel density of choriocapillaris was decreased(P<0.01)and the ET-1,ETAR and ETBR mRNA and protein levels in choroid were increased in LIM+EA group.CONCLUSION:In LIM guinea pigs,the choroidal blood flow decreased with the increased of refraction and axial length,which may affect ET-1 and its receptors through vascular shear force during the development of myopia.At the same time,electroacupuncture can improve choroidal blood flow through neuromodulation and affects the vascular shear stress to down-regulate the content of ET-1 and its receptor to delay the development of myopia.