The Effect Of Recombinant Human Interferon α-2b On CCI Pain Model In Rats

Objective:It conducts an intervertebral foramen injection for rats’ chronic constriction injury of the sciatic nerve by using recombinant human interferon α-2b, and through measuring thermal pain threshold and contents of p-p38 MAPK in spinal cord, it observes whether it has a treatment effect on neuropathic pain induced by CCI, and discusses and analyzes its possible mechanism.Methods:48 male rats were randomly divided into four groups: sham operation group, CCI group, 60,00 units group and 80,000 units group, with 12 rats in each group, and they are all male rats which were randomly selected. When conduct CCI model building of the sham operation group, it only cut and exposed the sciatic nerve and didn’t conduct a ligation was not performed. The other three groups were exposed to the sciatic nerve, and the 4 channels of 1mm were performed with a thread of silk. 1 day before surgery and after 1 day, 3 days, 7 days, the thermal pain threshold in each group were measured and it determined that the model building was successful. On the eighth day, the other three groups were treated with intervertebral foramen injection, except sham operation group. CCI group was given 0.5ml of normal saline, 60,000 units group was given 0.1ml of 60,000 units of recombinant human interferon α-2b, 80,000 units group was given 0.1ml of 80,000 units of recombinant human interferon α-2b, and sham operation group was given no treatment. One day and three days after retardation, each group was measured the thermal pain threshold. One day before injection, one day and three days after retardation, 4 rats in each group were randomly selected, and the spinal cord and dorsal root ganglia of L4-5 segment were taken out to conduct a splitting treatment. After that, the content of p-p38 MAPK in the samples was determined by enzyme linked immunosorbent assay(ELISA).Result:After CCI model building, the thermal pain threshold showed that, compared with the sham operation group, the thermal pain threshold of other three groups was significantly reduced, and the difference was statistically significant(P< 0.05), which showed that CCI model building was successful. 1 and 3 days after the intervertebral foramen injection, the thermal pain threshold of each pain model group(group CCI, 60,000 units group, 80,000 units group) showed no significant difference(P> 0.05).The statistical analysis indicated that the content of p-p38 MAPK of each pain model group was significantly increased compared with the sham operation group(P< 0.05), but there was no significant statistical difference among the pain model groups(P > 0.05).Conclusion:1. p-p38 MAPK of spinal cord and dorsal root ganglion is involved in the formation and maintenance of a neuropathic pain.2. The dose of Recombinant Human Interferon α-2b used in this experiment has no significant influence on the thermal pain threshold of neuropathic pain caused by rat CCI model.3. The dose of Recombinant Human Interferon α-2b used in this experiment has no significant influence on the expression quantity of p- p38 MAPK in CCI model rats’ spinal cord and dorsal root ganglia.