The present invention provides a therapy for treating neuropathic pain by subpial administration of small quantities of a composition for spinal segment-specific upregulation of GAD65 (glutamatedecarboxylase) gene and VGAT (vesicular GABA transporter) gene, which is effective for induction of nociceptive effects by potentiating release of vesicular GABA from infected dorsal horn neurons into the synaptic cleft.