L-精氨酸和氨基胍对实验性脑缺血损伤的影响

Effects of the L-arginine and aminoguanidine on the experimental cerebral ischemic injury

目的观察一氧化氮 (nitricoxide ,NO)供体L 精氨酸 (L arginine)和一氧化氮合酶抑制剂氨基胍 (aminoguanidine,AG)对实验性大鼠局灶性脑缺血损伤的治疗作用以及一氧化氮在脑缺血损伤中的作用规律。方法用线栓法建立大鼠大脑中动脉脑缺血 (MCAO)模型后注射L 精氨酸和AG ,研究大鼠脑缺血后脑梗塞体积变化 ;脑组织中NO、丙二醛 (MDA)含量和一氧化氮合酶(NOS)、超氧化物歧化酶 (SOD)活性的变化 ;缺血脑组织病理变化。结果单独给予L 精氨酸或氨基胍均可明显缩小脑梗塞体积 ,明显降低缺血脑组织MDA含量 ,增强SOD活性 ;L 精氨酸还可明显增加缺血脑组织NO含量 ,氨基胍可明显抑制缺血脑组织NOS活性 ;L 精氨酸与氨基胍合用时 ,上述各项指标与缺血组比较无明显变化。结论L 精氨酸与氨基胍分别单独应用 ,对脑缺血性损伤具有治疗作用 。

Objective To observe the role of the nitric oxide and the effect of the nitric oxide donor L arginine and nitric oxide synthase inhibitors aminoguanidine(AG) on the focal cerebral ischemic injury in rats.Methods The AG and L arginine were administrated after the rat model with focal cerebral ischemia was established with the middle cerebral artery occlusion(MCAO). The changs of the cerebral infarct volume,NO,MDA content,NOS,SOD activity and pathological changes in the focal ischemic cerebral tissues were determined.Results Administration of the L arginine or AG alone reduced the infarct volume ( P <0 05 versus vehicle),decreased the MDA content,enhanced the SOD activity in the focal ischemic cerebral tissues.Administratinon of the L arginine alone increased the NO content.Administration of aminoguanidine alone inhibited the NOS activity.Conclusions Administration of the L arginine or aminoguanidine alone,but not the L arginine and aminoguanidine combinative,has beneficial therapeutic effect on the cerebral injury at the ischemic acute stage.