Collectively, we believe that this data significantly increases our understanding of one of the mechanisms underlying the development of neuropathic pain by demonstrating that the modulation of astrocyte P450c17 expression is closely associated with an early increased release of IL-1β in the lumbar spinal cord dorsal horn and this P450c17 modulation of IL-1β ultimately affects the development of MA induced by peripheral nerve injury. The gene discussed is IL1B; the disease is microtia.