鞘膜内注射一氧化氮合酶抑制剂对损伤脊髓血流及功能的影响

The effect of intrathecal administration of nitric oxide synthase inhibitor on blood flow and function of injurious spinal cord in rats

目的：探讨一氧化氮（ＮＯ）在继发性脊髓损伤中的作用。方法：伤前３０ｍｉｎ鞘膜内注射不同剂量的一氧化氮合酶（ＮＯＳ）抑制剂亚硝基左旋精氨酸甲酯（Ｌ－ＮＡＭＥ），观察其对伤段脊髓血流量及神经功能的影响。结果：小剂量的Ｌ－ＮＡＭＥ降低了伤段脊髓早期局部血流量，但改善了损伤脊髓的神经功能；而大剂量的Ｌ－ＮＡＭＥ则长时间内严重地减少了伤段脊髓血流量，加重了伤段脊髓神经功能损伤。结论：脊髓损伤早期伤段脊髓ＮＯ适度产生有利于神经功能恢复。

Objective: To explore the effect of nitric oxide (NO) on the secondary spinal cord injury. Methods: The different doses of nitric oxide synthase(NOS) inhibitor, N ω nitro L arginine methyl ester (L NAME), were infused into spinal subarachnoid space 30 min before spinal cord injury( SCI), and spinal cord blood flow( SCBF) at trauma sites was monitored, neurological function was evaluated. Results: The early SCBF was reduced with the small dose of L NAME, and neurological function was ameliorated; but the large dose of L NAME resulted in spinal cord ischemia for a long time, and worsened acute spinal cord injury. Conclusion: The moderate production of NO in early damaged spinal cord benefits restore of neurological function, but the significant restriction of NO production can worsen the secondary spinal cord injury.