Bosentan对大鼠脊髓缺血再灌注损伤后一氧化氮及一氧化氮合酶表达的影响

目的观察非选择性内皮素受体阻断剂Bosentan对大鼠脊髓缺血再灌注损伤(SCIRI)后一氧化氮(NO)及一氧化氮合酶(NOS)表达的影响及其意义。方法健康雄性SD大鼠90只,建立SCIRI模型,分为正常组、假手术组、单纯缺血组(I)、生理盐水(NS)干预对照组、Bosentan干预组(Bos),NS和Bos组又以再灌注(IR)时间分为3、6、12、24、48、72h组,测定血清NO含量,免疫组织化学染色检测nNOS、iNOS和eNOS表达变化。结果①SCIRI后血清NO表达呈双峰样改变,峰值分别出现于IR3h及24h,Bosentan可显著降低第二个峰值(P<0.05)。②SCIRI后nNOS、iNOS、eNOS在脊髓中的表达均逐渐增加,并分别于IR后24、48、24h达峰值,Bosentan可显著下调nNOS、iNOS表达(P<0.05),上调eNOS表达(P<0.05)。③SCIRI后脊髓FADD蛋白、TrkA蛋白表达均逐渐增加,分别于IR后24、12h达峰值,Bosentan干预可下调FADD表达(P<0.05),上调TrkA含量(P<0.05)。结论 Bosentan可影响大鼠SCIRI病理过程中NO及nNOS、eNOS、iNOS的表达,其机制可能与调节FADD及TrkA表达有关。

Effect of Bosentan on expression of NO and NOSs in spinal cord ischemia-reperfusion injury

ObjectiveTo study the influece of Bosentan on the expression and significance of nitric oxide(NO) and nitric oxide synthase(NOS) after spinal cord ischemia-reperfusion injury.MethodsThe rats were randomly assigned to 4 groups: normal group(Normal),sham group(Sham),ischemia group(I),NS and Bos group.The rats in the NS group had spinal cord ischemia reperfusion injury and saline intraperitoneal injection before aortic clamping and reperfusion.The rats in Bosentan groups was injected with Bosentan.The NS and Bos groups are divided into reperfusion 3h,6h,12h,24h,48h,72h group according to reperfusion time,serum NO content was assayed.The nNOS in iNOS and eNOS expression was evaluated using immunohistochemical method.Results①SIRI could cause the increase of NO and the bimodal dynamic characteristic was noticed.The first peak came at the reperfusion 3h and the latter at 24h.Bosentan intervention could significantly reduce serum NO of the second peak(P<0.05),while there was no significant effect on the former.The nNOS protein expression was gradually increased and peaked at IR24h after SIRI,but could significantly reduced from Bosentan intervention and the change was statistically significant(P<0.05).②The iNOS protein expression increased gradually and peaked at 48h in the spinal cord after SIRI,but could significantly reduce from Bosentan intervention and the change was statistically significant(P<0.05).The expression of eNOS protein increased gradually and peaked at 3h after SIRI and can significantly increased from Bosentan intervention also the change was statistically significant(P<0.05).③After SIRI the apoptin FADD gradually increased its peak at 24h compared to I group.Bosentan could significantly reduced the expression compared to its counterpart at same time point.Also the TrkA can gradually increased its peak at 12h Bosentan can significantly increased the expression of TrkA at 6h.Conclusion Non-selective ET receptor antagonist Bosentan may affect the expression of nNOS,eNOS,iNOS and production of NO after SIRI pathology in rats and improve ischemia-reperfusion-induced injury by regulating the expression of apoptotic proteins FADD and survival factor TrkA to participate in SIRI.