PAF受体拮抗剂对脊髓损伤后花生四烯酸代谢的影响

Effects of PAF receptor antagonist on arachidonic acid metabolism in spinal cord tissue after trauma

目的：为了探讨ＰＡＦ受体阻断对脊髓损伤后脊髓组织花生四烯酸代谢的作用及ＰＡＦ受体拮抗剂对脊髓损伤的治疗作用机制。方法：应用ＰＡＦ受体拮抗剂ＢＮ５２０２１造成猫体内脊髓损伤前、后ＰＡＦ受体部分阻断，分别采用微量滴定法、１２５Ｉ放射免疫分析法测定脊髓损伤后６ｈ脊髓组织ＰＬＡ２活性及花生四烯酸代谢产物（ＴＸＢ２、６－ｋｅｔｏ－ＰＧＦ１ａ）含量。结果：伤后脊髓组织ＰＬＡ２活性、ＴＸＢ２、６－ｋｅｔｏ－ＰＧＦ１ａ含量均明显增高（Ｐ＜０．０５），而ＰＡＦ受体阻断组伤后脊髓组织ＰＬＡ２活性、ＴＸＢ２、Ｔ／Ｋ值较单纯脊髓损伤组明显降低（Ｐ＜０．０５）。结论：表明ＰＡＦ受体及其受体拮抗剂对脊髓损伤后脊髓组织ＰＬＡ２活性、ＴＸＡ２的合成及Ｔ／Ｋ值具有调控作用，提示ＰＡＦ受体拮抗剂能够防治脊髓损伤后继发性损害。

Objective:To investigate the effect of PAF receptor blockade on arachidonic acid metabolism in spinal cord tissue after trauma and effective mechanism on treatment of spinal cord injury with PAF receptor antagonist.Methods:Partial blockade of internal PAF receptor was performed by using PAF receptor antagonist BN52021 before or after spinal cord injury. PLA2 activity and arachidonic acid metabolites(TXB2 and 6-keto-PGF1a,)levels in spinal cord tissue at 6 h after trauma were measured by microtitration and125 I radioimmune analysis.Results:PLA2 activity,TXB2 and 6-keto-PGF1a levels and T/K ratio significantly increased in spinal cord tissue after trauma(PMO<0.05).However,PLA2 activity,TXB2 level and T/K ratio of PAF receptor blockade group in spinal cord tissue after trauma significantly decreased compared to simple spinal cord injury group(PM<0.05). Conclusion: Our results demonstrate that PAF receptor and PAF receptor antagonist could regulate PLA2 activity, TXA2 level and T/K ratio in spinal cord tissue after trauma. The studies suggest that PAF receptor antagonist has a potential role in preventing and treating secondary damage after trauma.