Role of NF-κB pathway in the development of intrathecal platelet- activating factor- induced hyperalgesia in rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the role of NF-κB pathway in the development of intrathecal(IT)platelet-activating factor (PAF)-induced hyperalgesia in rats. Methods Sixty-four male SD rats (200-250 g) in which intrathecal catheters were successfully implanted without complications were randomly divided into 6 groupsgroup Ⅰ received artificial cerebro-spinal fluid (ACSF) 10 μl IT (n = 16); group Ⅱ received PAF 10 μg in ACSF 10 μl IT; group Ⅲ received 0.1% DMSO 2 ml intraperitoneally (IP) (n = 8); group Ⅳ, Ⅴ, Ⅵ received IP SC-514 (a selective IKK-β inhibitor) 10, 50, 100 mg/kg in 0.1% DMSO 2 ml respectively at 2 h before IT PAF. Paw withdrawal threshold to mechanical stimulation (PWMT) and paw withdrawal latency to thermal stimuli (PWTL) were measured before (baseline) and at 5, 15, 30, 45, 60 min and then every 30 min for another 4 h after IT administration. The animals were killed after the last pain threshold measurement at 5 h after IT PAF. The lumbar segment (L4-6) of the spinal cord was removed for determination of TNF-α and IL-lβ content (by ELISA).Results lntrathecal PAF induced tactile allodynia and thermal hyperalgesia rapidly, increased the expression of TNF-α and IL-lβ in lumbar spinal cord. Pretreatment with SC-514 attenuated PAF-induced hyperalgesia and inhibited the increase in TNF-α and IL-1β expression in the spinal cord. Conclusion NF-κB is involved in intrathecal PAF-induced hyperalgesia.