Increased ciliary neurotrophic factor expression in reactive astrocytes following spinal cord injury in the rat

Expression of ciliary neurotrophic factor (CNTF) was observed in reactive astrocytes in injured spinal cord of the adult rat. After unilateral incision of the dorsal funiculus at a midthoracic level, the rats were sacrificed on the day of postoperation (DPO) 3, 7, 14 or 28. Western blot analysis of spinal cord extracts showed that the intensity of the CNTF-immunoreactive band of 24 kDa was increased on DPO 3 and 7 and decreased on DPO 14. CNTF- or glial fibrillary acidic protein (GFAP)-like immunoreactivity was also increased progressively in the injured dorsal funiculus and adjacent gray matter. Double immunofluorescence histochemistry revealed that all CNTF-like immunoreactive cells showed GFAP-like immunoreactivity. The CNTF upregulation in the reactive astrocytes may play important roles in repair process after spinal cord injury.