Asami Yasuyuki, Nakahara Tsutomu, Asano Daiki, Kurauchi Yuki, Mori Asami, Sakamoto Kenji, Ishii Kunio
Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences , Tokyo , Japan , and.
Curr Eye Res. 2015 May;40(5):549-53. doi: 10.3109/02713683.2014.933851. Epub 2014 Jun 30.
Previous studies have shown that injury to the retinal vasculature, including capillary degeneration, occurs following N-methyl-d-aspartate (NMDA)-induced neuronal cell loss, but it is unclear whether there are age-dependent differences in the severity of vascular damage. The purpose of the present study was to determine age-related changes in retinal capillary degeneration in NMDA-induced retinal damage rat model.
A single intravitreal injection of NMDA (200 nmol/eye) was performed in 1-, 2-, 3-, 7- and 15-week-old male Sprague-Dawley rats. Seven days after NMDA injection, damage to retinal neurons and blood vessels were assessed by measuring the number of cells in the ganglion cell layer and the length of empty basement membrane sleeves, left behind by regressing endothelial cells, respectively.
At all ages examined, the NMDA-induced neurotoxicity exhibited similar levels of ganglion cell death. However, the degeneration of capillaries in NMDA-treated retina was severe during the early stages of retinal vascular development, and the degree of capillary degeneration decreased with age.
The degree of retinal capillary degeneration in NMDA-induced retinal damage rat model decreases in an age-dependent manner. Retinal capillaries may be resistant to retinal neuronal damage in young adults.
先前的研究表明，在N-甲基-D-天冬氨酸（NMDA）诱导的神经元细胞丢失后，包括毛细血管变性在内的视网膜血管系统会受到损伤，但尚不清楚血管损伤的严重程度是否存在年龄依赖性差异。本研究的目的是确定NMDA诱导的视网膜损伤大鼠模型中视网膜毛细血管变性的年龄相关变化。
对1周龄、2周龄、3周龄、7周龄和15周龄的雄性Sprague-Dawley大鼠进行单次玻璃体内注射NMDA（200 nmol/眼）。NMDA注射7天后，分别通过测量神经节细胞层中的细胞数量和消退的内皮细胞留下的空基底膜套的长度来评估视网膜神经元和血管的损伤情况。
在所有检测的年龄组中，NMDA诱导的神经毒性表现出相似水平的神经节细胞死亡。然而，在视网膜血管发育的早期阶段，NMDA处理的视网膜中的毛细血管变性严重，并且毛细血管变性的程度随年龄增长而降低。
在NMDA诱导的视网膜损伤大鼠模型中，视网膜毛细血管变性的程度呈年龄依赖性降低。视网膜毛细血管在年轻成年个体中可能对视网膜神经元损伤具有抗性。
