Temporal and Spatial Variation of ski-interacting Protein Expression in Rats after Spinal Cord Injury and its Role / 中国康复理论与实践

ABSTRACT

Objective To explore the expression and change of ski-interacting protein (SKIP) in rats after spinal cord injury. Methods A total of 60 adult female Sprague-Dawley rats were randomly divided into sham group (n=30) and spinal cord injury (SCI) group (n=30), each group was further divided into five time points including one day, three days, five days, seven days, and 14 days with six rats in each time points. The model was established at T10 with modified Allen's technique, and the sham group only bit the lamina of rats. The hindlimbs behavior was assessed with Basso-Beattie-Bresnahan (BBB) score at each time point. The pathological changes of spinal cord neurons were detected with Nissl staining. The expression of SKIP were observed with immunofluorescence staining. Results The BBB scores were signif-icantly lower in each time point in SCI group than in the sham group (t>48.267, P<0.001). Compared with the sham group, Nissl bodies in the cytoplasm of spinal cord neurons began to disintegrate, coalesce and irregularly distribute, the neurons began to degenerate and die on the fifth day, and the damage deteriorated on the 14th day. Immunofluorescence staining showed that SKIP expression was mainly expressed in the gray matter of the spinal cord and little expressed in the white matter. The expression of SKIP gradually increased after SCI, and reached a peak on the fifth day (t=-17.035, P<0.001) and decreased significantly on the 14th day (t=3.853, P<0.05). Conclusion SKIP may be a new signaling molecule, which play an important role in neuronal apoptosis after SCI.