消旋山莨菪碱对豚鼠形觉剥夺性近视的作用和安全性

The safety and efficacy of racanisodamine on form-deprivation in guinea pigs

目的探讨10%消旋山莨菪碱对豚鼠形觉剥夺性近视的作用及安全性。方法 2～3周龄英国短毛花色豚鼠30只,随机分为3组,每组10只,采用右眼遮盖半透膜建造形觉剥夺模型。左眼为自身对照;A组:形觉剥夺+10%消旋山莨菪碱20μL玻璃体腔注射1次;B组:形觉剥夺+生理盐水20μL玻璃体腔注射1次;C组:单纯形觉剥夺组。所有动物饲养于500 lx白光照明环境中,照明周期12 h。干预前后用A超测量眼轴长度、前房深度和晶状体厚度,计算玻璃体腔长度;带状光检影法测量屈光度;右眼与左眼的差异作为评价指标以消除饲养过程中的组间差异。2周后实验结束,每组随机选取2只豚鼠处死后立即摘取眼球,行苏木素-伊红(HE)染色,观察眼部组织结构。结果各组基线左右眼眼轴长度、前房深度、晶状体厚度、玻璃体腔长度、屈光度差异均无统计学意义(P>0.05)。干预后2周复测,A组左右眼眼轴长度和玻璃体腔长度差异小于B组及C组,差异有统计学意义(P<0.01),玻璃体腔长度差异与眼轴长度差异显著相关(r=0.904,P<0.001)。各组间左右眼屈光度、晶状体厚度、前房深度差异均无统计学意义(P>0.05)。HE染色后显微镜下观察:给药组视网膜、巩膜、脉络膜均未见毒性改变。结论 10%消旋山莨菪碱可抑制豚鼠形觉剥夺性近视眼轴的增长,主要抑制玻璃体腔长度。10%消旋山莨菪碱玻璃体腔注射未发现组织学毒性改变。

Objective To investigate the safety and efficacy of 10% racanisodamine on form-deprivation in guinea pigs. Methods Thirty guinea pigs aged from 2 to 3 weeks were randomly divided into 3 groups （n = 10）. Formdeprivation models were established in right eyes with translucent membranes while the left eyes were treated as control. Group A was form-deprivation with intravitreal injection of 20 μL 10% racanisodamine for one time. Group B was form- deprivation with intravitreal injection of 20 μL saline for one time. Group C was form-deprivation group. All animals were raised in 500 lx white light environment, with the lighting period of 12 h a day. Axial length, anterior chamber depth and lens thickness was measured by ultrasound, then the vitreous length was calculated. Refraction was measured by retinoscopy. Measurements were carried out before and 2 weeks after intervention and the difference between right and left eye was evaluated to eliminate the intergroup disparity during growing. Hematoxylin eosin staining was performed to observe the microstructure of eyes under microscope. Results There was no significant difference in the baseline value of biometric measurements （P 〉 0.05）. The difference in axial and vitreous length between right and left eye was significantly smaller in group A than in the other two groups （P 〈 0.05 ）. The difference in vitreous length was significantly correlated to that in axial length （P 〈 0.05）. No significant difference was found in refraction, lens thickness or anterior chamber depth between bilateral eyes among the groups （P 〉 0.05）. No toxic change in retina, sclera or choroid was found after racanisodamine injection. Conclusions 10% racanisodamine may prevent the axial elongation of form-deprivation myopia in guinea pigs, mainly through the inhibition of vitreous length elongation. No toxic change was found after intravitreal injection of 10% racanisodamine.