IL1B and microtia: In conclusion, the present study demonstrates that the expression of IL-1β is significantly increased in the ipsilateral lumbar spinal cord dorsal horn of CCI mice and that blockade of central IL-1β signaling by intrathecal administration of IL-1 receptor antagonist during the induction phase of neuropathic pain not only facilitates the development of MA, but also increases both astrocyte P450c17 expression and pathological astrocyte activation in CCI mice.