Role of IL-1β and TNFα in the spinal cord in a murine model of bone cancer pain reduced by activation of glial cells / 中华麻醉学杂志

ABSTRACT

Objeetlve To evaluate the role of IL-1β and TNF-α in the spinal cord in a murine model of bone cancer pain(BCP)induced by activation of glial cells.Methods Three hundred and sixty male 8-10 weeks old C3H/He mice weighing 18-22 g were randomly divided into 6 groups(n=60 each):group I nomal control (group N);group Ⅱ sham operation (group S);group Ⅲ BCP+aCSF(group aCSF);group Ⅳ BCP+FC (group FC);group V BCP+MI(group MI) and group Ⅵ BCP+FC+MI (group FC-MI).BCP was produced by inieeting fibrosarcoma cells of bone into the medullary cavity of left ealcaneus bone.Intrathecal catheter was placed in the 4 BCP groups(group Ⅲ-Ⅳ).FC 0.5 nmol/5 μl or/and MI 16 μg/5 μl were injected IT once a day for 21 consecutive days after operation.The mechanical threshold to von Frey filaments was measured at 0.5 h(T0)before injection of fibrosarcoma cells and at 3,5,7,10,14,21 d(T1-6)after injection of fibrosarcoma cells.Twelve animals of each group were killed and L4.5 segment of the spinal cord was removed at T0,1,3,5,6 for determination of IL-1β and TNF-α content (by ELISA) and expression (by immuno-flurorescence) in the spinal cord. Results The mechanical threshold was significantly decreased at T1-6, while IL-1β content at T1,3,5,6 and TNF-α content at T5,6 was significantly increased in group BCP, FC, MI and FC + MI compared with those at T0 and group C (P < 0.05). Compared with group BCP, the mechanical threshold was significantly increased at T1-6 in group MI and FC + MI and at T4-6 in group FC, IL-1β content was significantly decreased at Ts,3,5,6 in group MI and FC + MI and at T5,6 in group FC and TNF-α content was significantly decreased at T5,6 in group FC, MI and FC + MI ( P < 0.05). Conclusion IL-1β and TNF-α in the spinal cord is involved in the process of glial cell activation-induced BCP.