The present invention relates to a novel use of substance P. The substance P of the present invention exhibits effects of decreasing microglia activity, decreasing proinflammatory cytokines, inhibiting apoptosis, etc. The substance P of the present invention effectively treats degenerative central nervous system diseases or disorders such as a spinal cord injury caused by a traumatic injury (flexion injury, vertical compression injury, hyperextension injury, flexion-rotation injury) and by a non-traumatic injury (vascular dysfunction, arthritis, or degenerative arthritis), Parkinsons disease, Alzheimers disease, amyotrophic lateral sclerosis, Huntingtons disease, depressive disorder, epilepsy, etc.
