Influence of intravascular low level He-Ne laser irradiation on iNOS, total-NOS, and ET-1 in acute spinal cord-injured rabbits

Objective To research the influence of intravascular low level Laser irradiation (ILLLI) on total NOS, iNOS, and ET-1 in spinal cord following acute spinal cord injury (ASCI), and discuss the protective effects of ILLLI on neurons. Methods 72 rabbits were randomly divided into 3 groups: treatment group, injury group and control group. In treatment group and injury group, after laminectomy at the level of T-13, ASCI was performed by using Allen's method with slight modification (6g×10cm) on rabbits. After injury, rabbits were treated immediately with He-Ne laser (power 5 mW, 1 hour per day for 10 days). At the day of 10th after treatment, total-NOS, iNOS, and ET-1 in spinal cord tissues were measured. Results The expression level of total-NOS, iNOS, and ET-1 in spinal cord in injury group were significantly higher than those in control group (P<0.05), while after ILLLI the level of these index in treatment group decreased statistically significantly compared with those in injury group (P<0.05). Conclusion ILLLI can significantly decrease the expression level of total-NOS, iNOS, and ET-1 in spinal cord. It indicates that ILLLI can relieve the overexpression of total-NOS, iNOS, and ET-1, and thus can perform protective effects on neurons in the course of secondary spinal cord injury (SSCI) following ASCI