遗传性视网膜变性视细胞凋亡与视网膜诱生型一氧化氮合酶活性的时程变化

Photoreceptor apoptosis and inducible nitric oxide synthase activity in inherited retinal degeneration of RCS rats

目的 研究遗传性视网膜变性视细胞凋亡与诱生型一氧化氮合酶活性之间的关系。方法 对生后不同鼠龄ＲＣＳ大鼠和Ｗｉｓｔａｒ大鼠的视网膜进行凋亡细胞的ＴＵＮＥＬ检测、计算机自动图像分析及诱生型一氧化氮合酶活性的测定。结果 ＲＣＳ大鼠视网膜视细胞自生后第２５天出现凋亡，第３０～３５天达高峰；视细胞凋亡初期，即生后第２５天，视网膜诱生型一氧化氮合酶活性达高峰。结论 在遗传性视网膜变性的视网膜，诱生型一氧化氮合酶激活可能在视细胞凋亡中起诱导作用。

Objective To investigate the relation of photoreceptor apoptosis and inducible nitric oxide synthase activity in inherited retinal degeneration of Royal College of Surgeons(RCS) rats. Methods The retinas of RCS rats,ranging from 9th to 60th postnatal days in age,were studied by TdT-mediated biotin-dUTP nick-end labeling(TUNEL) for apoptosis and computer au- tomated image analysis. Inducible nitric oxide synthase(iNOS) activity was assayed in the whole retinal homogenates of RCS rats and wistar rats by monitoring the conversion rate of 3H-arginine to 3H-citrulline. Results The photoreceptor of RCS rats un- derwent apoptosis from 25th postnatal day, and reached the highest level at 30 - 35th postnatal days. At the early stage of photore- ceptor apoptosis, the level of iNOS activity in the retina increased significantly. Conclusion In the retinas of inherited retinal degeneration of RCS rats,nitric oxide generated by iNOS might play a significant role in photoreceptor apoptosis.