Department of Orthopaedic Surgery, Graduate School of Medicine, Yamaguchi University, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505, Japan.
J Clin Biochem Nutr. 2012 Jul;51(1):68-75. doi: 10.3164/jcbn.D-11-00011. Epub 2012 Feb 18.
Recently, arginase is suggested to regulate nitric oxide production by competing with nitric oxide synthase for the same substrate, L-arginine, in experimental asthma. We investigated the role of arginase and its relationship to nitric oxide production after spinal cord injury. Rats were subjected to laminectomy and complete transection of their spinal cords (injury group) or laminectomy only (sham group). In the injury group, arginase I was increased in the macrophages at the transection edge, and the peak was observed 48 h after spinal cord injury. However, nitric oxide production decreased significantly in the injury group despite increased nitric oxide synthase2 mRNA expression compared with the sham group. We also demonstrated the reduction in L-arginine concentrations, which was inversely associated with changes in arginase activity. Therefore, arginase appeared to regulate nitric oxide production by consuming L-arginine. The regulation of arginase activity and L-arginine levels may improve nitroxidative stress and reduce tissue damage in spinal cord injury.
最近，精氨酸酶被认为通过与一氧化氮合酶竞争相同的底物 L-精氨酸来调节一氧化氮的产生，这在实验性哮喘中得到了证实。我们研究了精氨酸酶的作用及其与脊髓损伤后一氧化氮产生的关系。大鼠接受椎板切除术和脊髓完全横断（损伤组）或仅椎板切除术（假手术组）。在损伤组，精氨酸酶 I 在横断边缘的巨噬细胞中增加，并且在脊髓损伤后 48 小时观察到峰值。然而，尽管与假手术组相比，损伤组中一氧化氮合酶 2 mRNA 的表达增加，但一氧化氮的产生显著减少。我们还证明了 L-精氨酸浓度的降低，这与精氨酸酶活性的变化呈负相关。因此，精氨酸酶似乎通过消耗 L-精氨酸来调节一氧化氮的产生。精氨酸酶活性和 L-精氨酸水平的调节可能改善脊髓损伤中的氮氧化物应激并减少组织损伤。
