Koga Takahisa, Koshiyama Yasuo, Gotoh Tomomi, Yonemura Naoko, Hirata Akira, Tanihara Hidenobu, Negi Akira, Mori Masataka
Department of Molecular Genetics, Kumamoto University School of Medicine, Kumamoto, Japan.
Exp Eye Res. 2002 Dec;75(6):659-67. doi: 10.1006/exer.2002.2062.
The regulation of expression of the arginine-recycling enzymes and arginase isoforms in association with inducible nitric oxide synthase (iNOS) in the eye of endotoxin-induced uveitis (EIU) rats is investigated. An animal model of EIU was created in Wistar rats by intravitreal injection of lipopolysaccharide (LPS). mRNAs for argininosuccinate synthase (AS) and arginase I as well as for iNOS, measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), were induced in the eye of EIU rats. iNOS mRNA increased markedly 3 hr after injection, reached a maximum at 6-12 hr, and then decreased at 24 hr. AS mRNA remained little change at 3 hr and increased maximally at 6 hr (by about 3.3-fold), whereas arginase I mRNA increased later and reached a maximum at 12 hr (by about 4.2-fold). iNOS, AS, and arginase I proteins were also induced. AL and arginase II mRNAs remained little changed. In immunohistochemical analysis, iNOS, AS and arginase I were almost colocalized in infiltrated inflammatory cells in the vitreous, iris, ciliary body and inner layers of the retina. In conclusion, AS and arginase I are coinduced with iNOS in infiltrated inflammatory cells in the eyes of EIU rats, and may regulate NO production by changing intracellular concentration of arginine.
研究了内毒素诱导性葡萄膜炎（EIU）大鼠眼中精氨酸循环酶和精氨酸酶同工型与诱导型一氧化氮合酶（iNOS）相关的表达调控。通过玻璃体内注射脂多糖（LPS）在Wistar大鼠中建立EIU动物模型。通过半定量逆转录-聚合酶链反应（RT-PCR）测定，EIU大鼠眼中精氨琥珀酸合成酶（AS）、精氨酸酶I以及iNOS的mRNA被诱导。注射后3小时iNOS mRNA显著增加，在6-12小时达到最大值，然后在24小时下降。AS mRNA在3小时变化不大，在6小时最大增加（约3.3倍），而精氨酸酶I mRNA增加较晚，在12小时达到最大值（约4.2倍）。iNOS、AS和精氨酸酶I蛋白也被诱导。AL和精氨酸酶II mRNA变化不大。在免疫组织化学分析中，iNOS、AS和精氨酸酶I几乎共定位于玻璃体、虹膜、睫状体和视网膜内层浸润的炎性细胞中。总之，在EIU大鼠眼中浸润的炎性细胞中，AS和精氨酸酶I与iNOS共同被诱导，并且可能通过改变细胞内精氨酸浓度来调节NO的产生。
