Resende Ana Paula, São Braz Berta, Delgado Esmeralda
Departamento de Clx00ED;nica, CIISA, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal.
Ophthalmic Res. 2016 Jul;56(2):104-10. doi: 10.1159/000444327. Epub 2016 Apr 15.
The present study aimed to determine whether the subconjunctival administration of recombinant human erythropoietin (rHuEPO) reached the retina in glaucoma conditions. After subconjunctival rHuEPO administration, in a rat glaucoma model, erythropoietin (EPO) distribution in the rat's retina was studied by immunohistochemistry.
Female Wistar Hannover albino rats (n = 15) were divided into 2 groups, control (n = 3) and treated (n = 12). The animals' unilateral glaucoma was induced by coagulation of episcleral veins, under general anaesthesia. After vein coagulation, 1,000 IU of rHuEPO were administered by the subconjunctival route to the treated group (n = 12). The control group (n = 3) received only a subconjunctival saline injection. The contralateral eye of each animal remained untouched. Treated group animals were euthanized at different time points, i.e. days 1, 3, 7 and 14. Bilateral enucleation was performed, and EPO distribution in the rat's retina was assessed by immunohistochemistry.
Glaucoma was confirmed by results of repeated intraocular pressure measurements over the experimental period. In the test group, EPO was identified in different neuroretinal cells, showing a stronger immunostaining signal during the first 2 time points in the retinal ganglion cell (RGC) layer. EPO protein was still present on day 14 after the subconjunctival injection. EPO was not detected in any of the control eyes or in any contralateral eye of the treated group.
When administered subconjunctivally to glaucomatous eyes, rHuEPO reached the RGC layer and was still present at least 14 days after administration. The subconjunctival route was shown to be a promising alternative for ocular EPO delivery in glaucomatous conditions in a rat animal model.
本研究旨在确定在青光眼情况下，结膜下注射重组人促红细胞生成素（rHuEPO）是否能抵达视网膜。在大鼠青光眼模型中，结膜下注射rHuEPO后，通过免疫组织化学研究促红细胞生成素（EPO）在大鼠视网膜中的分布。
将15只雌性Wistar Hannover白化大鼠分为2组，对照组（n = 3）和治疗组（n = 12）。在全身麻醉下，通过巩膜静脉凝固诱导动物单侧青光眼。静脉凝固后，治疗组（n = 12）通过结膜下途径给予1000国际单位的rHuEPO。对照组（n = 3）仅接受结膜下生理盐水注射。每只动物的对侧眼保持未处理状态。在不同时间点，即第1、3、7和14天，对治疗组动物实施安乐死。进行双侧眼球摘除，并通过免疫组织化学评估大鼠视网膜中EPO的分布。
通过实验期间重复测量眼压的结果证实了青光眼的存在。在测试组中，在不同的神经视网膜细胞中鉴定出EPO，在视网膜神经节细胞（RGC）层的前两个时间点显示出更强的免疫染色信号。结膜下注射后第14天仍存在EPO蛋白。在任何对照眼中或治疗组的任何对侧眼中均未检测到EPO。
当结膜下注射到青光眼眼中时，rHuEPO到达RGC层，并且在给药后至少14天仍然存在。在大鼠动物模型中，结膜下途径被证明是在青光眼情况下眼部递送EPO的一种有前景的替代方法。
