The Protective Effect Of 3-nitro-N-methyl Salicylamide On The Ischemia-reperfusion Injury Of The Lower Limbs Of SD Rats

Background:The treatment of lower limb ischemia-reperfusion injury has always been a challenging problem in the field of vascular surgery.Once it is not handled properly,it will cause tissue necrosis,amputation,and even damage other important organs of the body,critical patient's life.Therefore,ischemia-reperfusion injury of lower limbs is an extremely valuable issue in the field of general surgery.The consequences of lower limb ischemia-reperfusion injury are all related to abnormal burst of reactive oxygen species(ROS),and how to prevent the abnormal burst of ROS has become the key to the treatment of lower limb ischemia-reperfusion injury.3-Nitro-N-methyl-salicylamide is abbreviated as 3-NNMS,which is a kind of semi-mitochondrial inhibitor,which slows down the electron flow speed in the respiratory chain of mitochondria,and effectively inhibits the generation of ROS.Research purpose: This study intends to verify the therapeutic effect of(3-NNMS)in lower limb ischemia-reperfusion injury,and to provide experimental data support for future scientific research on related topics in vascular surgery.Research method: Twenty eight-week-old male SD rats were randomly divided into 4 groups,5 rats in each group.Ligation was used to ligate the roots of the right thighs of SD rats,and laser Doppler blood flow was used during ischemia.The monitoring system conducts blood flow monitoring on the right limbs of SD rats,and conducts ischemia for 1 hour,2 hours,3 hours,and 4 hours and 45 minutes,respectively,to explore the optimal ischemic conditions.After determining the ischemic time as 4 hours and 45 minutes,50 eight-week-old male SD rats were randomly divided into 5 groups,1)the blank control group(Con): no ischemia-reperfusion intervention,only PBS injection,2)0?g / ml group: ischemia reperfusion + 10% DMSO injection,3)25?g / ml: ischemia reperfusion + 25?g / ml 3-NNMS injection,4)125?g / ml:ischemia reperfusion + 125?g / ml of 3-NNMS injection,5)I/R + PBS : ischemia reperfusion ischemia-reperfusion + PBS injection.The reperfusion time was 2 hours.After the intervention,each SD rat's right lower limb rectus femoris tissue dissected,and the mitochondria of the rectus femoris muscle were extracted for mitochondrial energy performance test(CK-MM,LDH,MPO),inflammatory factors(NF-?b,TNF-?,IL-1?,COX-2),MDA and other indicators as well as HE staining were used to evaluate the function of the rectus femoris muscle and the degree of injury of the rectus femoris muscle.Results: After 4 hours and 45 minutes of ischemia and 2 hours of reperfusion,compared with the blank control group,the level of oxidative stress and inflammation damage of the rectus femoris muscle increased significantly,and the mitochondrial function was destroyed.But after adding 3-NNMS,the 3-NNMS group with a concentration of 125?g / ml can significantly increase the level of mitochondrial RCR(3.16 ± 0.22 vs 2.03 ± 0.51)compared with the 0?g / ml group.The oxidative stress test results show that After adding 3-NNMS,compared with the 0?g / ml group and I /R + PBS,the ROS level and MDA level in rectus femoris tissue were significantly reduced.The test of antioxidant enzyme activity showed that after adding 3-NNMS,It can significantly increase the activity of antioxidant enzyme SOD in rectus femoris muscle,and 3-NNMS at 125?g / ml can significantly increase the activity level of GSH-PX in rectus femoris muscle.The damage marker test results show that3-NNMS can significantly reduce CK-MM and LDH levels in rectus femoris muscle tissue.Inflammatory factor level test results show that 3-NNMS can significantly reduce the level of TNF-? in rectus femoris muscle,while 3-NNMS at a concentration of 125?g/ml can significantly reduce NF-?b in rectus femoris muscle,IL-1? and COX-2 levels.Research conclusion: Based on the analysis of the results of oxidative stress,antioxidant enzyme activity,inflammatory factors and damage markers,as well as mitochondrial related indicators,the results showed that 3-nnms could reduce the oxidative stress level of damaged muscle tissue,relieve the inflammatory response and damage of muscle tissue,and improve the level of mitochondrial RCR.In addition,the effect of 125?g/ml 3-NNMS was slightly better than that of 25?g/ml3-NNMS.