[Effects of different materials for partial sciatic nerve ligation on glial cell activation in rat models of chronic...

To compare the effects of different materials for partial sciatic nerve ligation on glial cell activation in the spinal cord in a rat model of chronic constriction injury (CCI).

SD rats were randomly divided into the sham group (n=15), silk suture CCI group (n=15) and chromic catgut CCI group (n=14). The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) of the rats were detected at 3, 7, 11 and 15 days after the operation. The changes in the sciatic nerve, the activation of spinal cord glial cells and the expression of inflammatory factors were observed using Western blotting and RT-PCR.

At 3 to 15 days after the surgery, MWT and TWL of the rats were significantly lower in silk suture group and chromic catgut group than in the control group (P < 0.05), and was significantly lower in chromic catgut group than in the silk suture group (P < 0.05) at 3 days after the surgery. The results of sciatic nerve myelin staining showed that the sciatic nerve was damaged and demyelinated in both the ligation groups. The expressions of CD11b, GFAP, IL-1β and TNF-α in the two ligation groups were similar and all significantly higher than those in the control group (P < 0.05). IL-6 mRNA level was significantly higher in chromic catgut group than in the silk suture group (P < 0.05).

The CCI models established by partial sciatic nerve ligation with silk suture and chromic catgut all show glial activation, and the inflammatory response is stronger in chromic catgut group.