The Mechanism And Protection Of Myocardial And Mitochondrion Injury After Amputation Trauma

Background and Objective:Stress is the adaptative and compositive reaction of the organism reacts to the destructive stimulus(stressor).surrounding stress,such as burns,ischemia and reperfusion,operation and so on may cause a series of reactions of neuroendocrine,oxidative stress and overload of Ca²⁺intracellular.in the same time,The organism can burn out considerable Angâ…¡, ALD,ET-1 and cytokine and active oxyradical,inducing irritable hypertension, arhythmia,myocardial ischemia and heart dysfunction.Limbs trauma is a stringent state and cardiovascular system is the chief target organ of stress.We have established the model of amputation trauma by surgery.Our experiment is divided into three parts.Firstly,we are to determine the H₂S,NO,MPO,MDA, Angâ…¡and ALD in plasma and activity of CSE enzyme,MPO,MDA,and ALD in cardiac tissue.Half quantitative PCR was employed to determine the levels of CaNAβmRNA in cardiac tissue.Electron microscope was used to obverse the pattern and function of mitochondrion.Secondly,we design to use the NaHS, PPG,spironolactone and FK506 to interfere in,observing the same index as above. Lastly,we determine the RCR,P/O,membrane potential and ATP of myocardial mitochondrion,to research the mechanism of myocardial and mitochondrion injury after amputation trauma.Method:We have established the model of amputation trauma by surgery.In the first part,sixty-three Wistar rats were divided into the control group,1h after trauma,2h,4h,6h,12h,24h,48h and 72h.there are seven rats in each class.In the second part,forty two Wistar rats were divided into six groups:the control group,trauma group:6h after trauma;NaHS group:6h after trauma +NaHS 28μmol/kg ip;PPG group:6h after trauma + PPG 50mg/kg ip;Spironolactone group:6h after trauma + spironolactone 20mg/kg intragastric administration for six days;FK506 group:6h after trauma +FK506 0.1mg/kg ip.In the last part, forty eight SD rats were divided into six groups as the second part..Result:The results of the fist part were as follows:All variables were compared with the control group.The levels of MPO,MDA in plasma and the levels of MPO,MDA in myocardium were significantly increased after trauma (P＜0.05),reached a peak 6h and 12h after trauma group,and then decreased slowly.The levels of H₂S,NO in plasma decreased significantly at 4h after trauma and toward baseline 6h after trauma.The myocardial level of CSE was markedly increased and reached a peak in 12h group.The results of the second part were as follows:All variables were compared with the 6h after trauma group. levels of H₂S,NO,MDA and ALD in plasma and the myocardial in NaHs group and FK506 group were significantly higher.The myocardial ALD,MDA,MPO and CSE activity in PPG group was significantly lower.MPO level in plasma was higher in NaHs group and lower in FK506 and PPG group.The results of the last part were as follows:compared to the control group,respiratory function of mitochondrion was broken-down and the levels of RCR,P/O,ATP and membrane potential were significantly lower.Compared to the trauma group, respiratory function of mitochondrion was improved and the levels of RCR,P/O,ATP and membrane potential were higher in NaHs and FK506 groups.The levels of RCR,P/O and ATP were decreased in PPG group.The levels of RCR,ATP and membrane potential in spironolactone group were higher.Conclution:amputation trauma can induce remote myocardial and mitochondrion injury.The mechanism may be involved in the activating of neutrophil and inflammatory cytokines,excess oxidative stress.Down-regulation of endogenous H₂S/CSE system and CaN signal transduction also participate in the myocardial and mitochondrion injury after amputation trauma.Exogenous H₂S and FK506 can protect myocardial injury after amputation trauma.