激动大麻素受体2对小鼠肝缺血再灌注损伤的预防效果

Efficacy of cannabinoid-2 receptor activation in preventing liver ischemia-reperfusion injury in mice

目的 探讨激动大麻素受体2对小鼠肝缺血再灌注损伤的预防效果.方法 健康雄性C57BL/6J小鼠48只,体重20 ～ 30 g,采用随机数字表法分为4组（n=12）：假手术组（S组）、肝缺血再灌注组（I/R组）、大麻素受体2激动剂组（J组）和大麻素受体2激动剂＋大麻素受体2拮抗剂组（JS组）.采用阻断肝动脉和门静脉30 min,再灌注45 min的方法制备肝缺血再灌注损伤模型.于缺血前60 min,J组腹腔注射大麻素受体2激动剂JWH133 20 mg/kg,JS组腹腔注射JWH 133 20 mg/kg和大麻素受体2拮抗剂SR144528 30 mg/kg.于再灌注45 min时,取肝组织,采用ELISA法检测肝组织TNF-α以及巨噬细胞炎症因子1α（MIP-1α）和MIP-2的含量,采用RT-PCR法检测肝组织TNF-α、MIP-1α、MIP-2和细胞间粘附分子-1（ICAM-1）的mRNA表达,并观察肝组织病理学结果.结果 与S组比较,I/R组、J组和JS组肝组织TNF-α、MIP-1α和MIP-2含量升高,TNF-α、MIP-1α、MIP-2和ICAM-1的mRNA表达上调（P＜ 0.05）;与I/R组比较,J组肝组织TNF-α、MIP-1α和MIP-2含量降低,TNF-α、MIP-1α、MIP-2和ICAM-1的mRNA表达下调（P＜0.05）,JS组上述指标差异无统计学意义（P＞0.05）;与J组比较,JS组肝组织TNF-α、MIP-1α和MIP-2含量升高,TNF-α、MIP-1α、MIP-2和ICAM-1的mRNA表达上调（P＜0.05）.J组肝组织较I/R组和JS组减轻.结论 激动大麻素受体2可对小鼠肝缺血再灌注损伤产生预防效果,机制与抑制肝组织炎性反应有关.

Objective To investitate the efficacy of cannabinoid-2 receptor （CB2R） activation in preventing liver ischemia-reperfusion （I/R） injury in mice.Methods Forty-eight male C57BL/6J mice,weighing 20-30 g,were divided into 4 groups （n =12 each）：sham operation group （group S）,group I/R,CB2R agonist JWH133 group （group J）,and CB2R agonist JWH133 ＋ CB2R antagonist SR144528 group （group JS）.Liver I/ R was produced by blocking the hepatic artery and portal vein for 30 min followed by 45 min of reperfusion in anesthetized mice.At 60 min before ischemia,JWH133 20 mg/kg was injected intraperitoneally in group J,and JWH133 20 mg/kg and SR144528 30 mg/kg were injected intraperitoneally in group JS.The liver was removed at 45 min of reperfusion for determination of tumor necrosis factor-α （TNF-α）,macrophage inflammatory protein-1α （MIP-1α） and MIP-2 contents （using ELISA）,and expression of TNF-α,MIP-1α,MIP-2 and intercellular adhesion molecule-1 （ICAM-1） mRNA （by RT-PCR） in the liver tissues and for microscopic examination of the pathological changes.Results Compared with group S,the contents of TNF-α,MIP-1α and MIP-2 were significantly increased,and the expression of TNF-α,MIP-1α,MIP-2 and ICAM-1 mRNA was up-regulated in J and JS groups.Compared with group I/R,the contents of TNF-α,MIP-1α and MIP-2 were significantly decreased,and the expression of TNF-α,MIP-1α,MIP-2 and ICAM-1 mRNA was down-regulated in J group,and no significant change was found in the parameters mentioned above in JS group.Compared with group J,the contents ofTNF-α,MIP-1α and MIP-2 were significantly increased,and the expression of TNF-α,MIP-1α,MIP-2 and ICAM-1 mRNA was up-regulated in JS group.The pathological changes of liver tissues were significantly attenuated in group J as compared with I/R and JS groups.Conclusion CB2R activation is effective in preventing liver I/R injury in mice and the mechanism is related to inhibitioni of inflammatory responses in liver tissues.