RESUMO
Objective: To explore the effect of umbilical cord blood stem cell transplantation on axon regeneration in spinal cord injury (SCl)in rats. Methods: The umbilical cord blood was collected and prepared into suitable concentration of CD34 positive stem cells. Thirty SD rats were divided into two groups randomly. One group served as control, another one was the treatment group. The models of spinal cord contusion injury were made by Allen's weight dropping method. One week later,the treatment group was transplanted with 10x105 umbilical cord blood stem cells with Hamilton micro-syringe at the sites of rostral and caudal to the lesioned zone respectively, while control group received just the same volume of PBS injection. Five rats in each group were sacrificed at 1 w, 2 w and 6 w after this operation. Histological and immunohistochemieal examinations including GAP-43 and NF200 were used to evaluate axon regeneration. Meanwhile, BBB motion scoring and inclined plane test were performed to assess the motion function changes of hindlimbs. Results: Compared to the control group, the area of cavity in the lesioned spinal cord region decreased significantly and the expressions of GAP-43 and NF200 increased markedly in cell transplantation group. Also the motion function had better restoration in the treatment group. Conclusion: Transplantation of umbilical cord blood stem cell may achieve both morphological and behavioral improvement for the injured spinal cord.