Spinal cord injury (SCI) commonly results not only in motor paralysis but also in the emergence of neuropathic pain, both of which can impair the quality of life for SCI patients. In the clinical field, it is well known that Pregabalin, which binds to the voltage-gated calcium channel alpha-2-delta-1 subunit (Cava2d-1) has therapeutic effect on neuropathic pain after SCI. Previous study has demonstrated that SCI increase Cava2d-1 in L4-6 dorsal spinal cord of SCI rats by Western blot and that the increase of Cava2d-1 correlated with tactile allodynia of the hind paw. However, the mechanisms of Pregabalin for SCI induced neuropathic pain are poorly understood. In this study we examined cellular distribution of Cava2d-1 expression in L4-6 spinal cord of SCI rats using immunohistochemistry.Spinal cord contusion injury was produced in male SD rats (200 g). Rats were anesthetized by intraperitoneal pentobarbital administration. The lamina of the T10 vertebrate was then removed. A contusion injury was generated using the IH impactor devise that emulates a 100-kilodyne weight-drop onto the dura mater from a distance of 4 mm(N=5). Sham control rats received laminectomy without the contusion injury (N=5). During pentobarbital anesthesia, perfusion fixation was performed using 1-4% paraformaldehyde and 0.1 M phosphate buffer solution (pH 7.4), the spinal cord (L4-6) was removed. The transverse sections were cut and processed for immunohistochemistry. Quantitative analysis was performed by NIH image software. Locomotor function recovery post SCI was monitored using BBB scale .Following SCI, the BBB scale was 2.4±0.6 at day 1, and increased to 12.4±0.6 four weeks after SCI, indicating improvement. In the naive rats we detected expression of Cava2d-1 immunoreactivity mainly in lamina I and II in the dorsal horn. SCI significantly increased Cava2d-1 immunoreactivity in lamina I and II in the dorsal horn at four weeks after SCI. These findings suggested that increase of Cava2d-1 in the L4/5 of dorsal horn after thoracic SCI was involved in the development of neuropathic pain in hindlimb.The increase of Cava2d-1 in superficial dorsal horn after SCI may be related to the Pregabalin's effect on central neuropathic pain.