Lei Yuan, Zhang Xuejin, Song Maomao, Wu Jihong, Sun Xinghuai
Research Centre Eye and ENT Hospital, Shanghai Medical College, Fudan University, China 2Key Laboratory of Myopia, Ministry of Health, Fudan University, China 3Shanghai Key Laboratory of Visual Impairment and Restoration, Eye and ENT Hospital, Shanghai Me.
Research Centre Eye and ENT Hospital, Shanghai Medical College, Fudan University, China 3Shanghai Key Laboratory of Visual Impairment and Restoration, Eye and ENT Hospital, Shanghai Medical College, Fudan University, China.
Invest Ophthalmol Vis Sci. 2015 Jul;56(8):4891-8. doi: 10.1167/iovs.15-16564.
To investigate the role of endothelial nitric oxide synthase (eNOS) on conventional outflow function using NOS3 knockout (KO) mice.
Intraocular pressure was measured in both NOS3 KO and wild type (WT) by rebound tonometry. Outflow facility was measured by perfusing enucleated mouse eyes at multiple pressure steps. A subset of eyes was sectioned and stained for histology. Mock aqueous humor ± the nitric oxide (NO) donors nitroprusside dihydrate (SNP) or S-Nitroso-N-Acetyl-D,L-Penicillamine (SNAP) was perfused into enucleated eyes. SNP and SNAP was administered topically at 0, 1, 2, and 3 hours while the contralateral eyes served as vehicle controls. Intraocular pressure was measured in both eyes before and after the last drug treatment.
Intraocular pressure was higher in KO mice (18.2 ± 0.7 mm Hg vs. 13.9 ± 0.5 mm Hg, mean ± SEM, n = 30, P < 0.05), and pressure-dependent conventional drainage was significantly lower (0.0058 ± 0.0005 μL/min/mm Hg, mean ± SEM, n = 21) compared with WT mice (0.0082 ± 0.0013 μL/min/mm Hg, n = 23, P < 0.05). No obvious morphological differences in iridiocorneal angle tissues were observed in hematoxylin and eosin (H&E)-stained sections. SNP and SNAP significantly increased pressure-dependent drainage in KO animals (n = 12, P < 0.05). In WT mice, SNP and SNAP caused a significant increase in pressure dependent drainage (n = 12, P < 0.05) to a similar degree as in KO mice. Topical application of SNP significantly reduced IOP in WT and KO mice (n = 12, P < 0.05), but SNAP did not change IOP significantly (n = 19).
NOS3 KO mice have elevated IOP, which is likely the result of reduced pressure-dependent drainage. These findings are consistent with human data showing polymorphisms in the NOS3 gene associate with ocular hypertension and the development of glaucoma.
利用一氧化氮合酶3基因敲除（KO）小鼠研究内皮型一氧化氮合酶（eNOS）在传统房水流出功能中的作用。
通过回弹眼压计测量NOS3 KO小鼠和野生型（WT）小鼠的眼压。在多个压力步骤下灌注摘除的小鼠眼球来测量房水流出易度。对一部分眼球进行切片并进行组织学染色。将模拟房水±一氧化氮（NO）供体二水合硝普钠（SNP）或S-亚硝基-N-乙酰-D,L-青霉胺（SNAP）灌注到摘除的眼球中。在0、1、2和3小时局部给予SNP和SNAP，对侧眼作为溶剂对照。在最后一次药物治疗前后测量两只眼睛的眼压。
KO小鼠的眼压较高（18.2±0.7毫米汞柱对13.9±0.5毫米汞柱，平均值±标准误，n = 30，P < 0.05），与WT小鼠相比，压力依赖性传统房水引流显著降低（0.0058±0.0005微升/分钟/毫米汞柱，平均值±标准误，n = 21）（WT小鼠为0.0082±0.0013微升/分钟/毫米汞柱，n = 23，P < 0.05）。在苏木精和伊红（H&E）染色切片中未观察到虹膜角膜角组织有明显形态学差异。SNP和SNAP显著增加了KO动物的压力依赖性房水引流（n = 12，P < 0.05）。在WT小鼠中，SNP和SNAP使压力依赖性房水引流显著增加（n = 12，P < 0.05），程度与KO小鼠相似。局部应用SNP显著降低了WT和KO小鼠的眼压（n = 12，P < 0.05），但SNAP未显著改变眼压（n = 19）。
NOS3 KO小鼠眼压升高，这可能是压力依赖性房水引流减少的结果。这些发现与人类数据一致，即显示NOS3基因多态性与高眼压症和青光眼的发生有关。
