Study Of Lung Injury After Trauma

Background and Objective:Trauma is the oldest project in medical science. Lung is the most easily impaired after trauma.Display acute lung injury,or pneumonedema even to death.surgical trauma is a different trauma,There is a direct relation between the lung injury and the trauma.It is a common pathophysiological phenomenon clinically.The mechanism of acute lung injury following trauma is very complicated.The mechanism may be involved in the activating of neutrophil and inflammatory cytokines,excess oxidative stress,the imbalance of oxidant-antioxidant system,high secreting of aldosterone.up to now,it has not completely elucidated yet.Our experiment is divided into two parts.Firstly,we explore the role of the neutrophils and inflammatory cytokines,oxidant-antioxidant system,aldosterone (ALD)and endogenous hydrogen sulfide(H₂S)/cystathionine-y-lyase(CSE) system,calcineurin,surfactant protein in the pathogenesy of lung injury after trauma.Secondly,we are to ascertain the mitochondria energy metabolism on the lung injury after trauma.Methods:In the first part,ninty-one Wistar rats were divided into 13groups at random:Group normal(C),Group 1h after trauma(B1),Group 2h(B2),Group 4h(B4),Group 6h(B6),Group 12h(B12),Group24h(B24),Group48h (B48),Group 72h(B72);and 4 groups with interventions:group-NaHS,group-PPG: group-FK506,group-aldactone.The plasma levels of H₂S,MPO,MDA, ALD,NO,Agâ…¡,IL-6,the ratio of wet to dry lung tissue weight(W/D)in each group were measured.IL-6,MPO,MDA,The CSE activity in lung were detected. and mRNA level of SP-A,SP-D,CaN-αwere detected. In the second part,forty-eight Wistar rats with 4h Group normal(C),Group 6h(B6),4 groups with interventions:group-NaHS,group- PPG;group-FK506, group-aldactone,mitochondria respiratory function,membrane potential,ATP enzymatic activity were detected.Results:Compared with Group normal,histopathologic results indicated lung injury following trauma.It indicated congestion,dropsy,phlegmonosis cell infiltrate,the damage of group B6 is the most serious,group PPG,group FK-506 indicated the damage decreased,group NaHS,group aldactone indicated no infinite damage or protection.Compared with Group normal,the levels of MPO,MDA,IL-6 in plasma inceased and the levels of MPO,MDA,IL-6 in lung were increased too;the levels of H₂S decreased after trauma like the level of CSE activity in lung.W/D increased after trauma indicate that there are pneumonedema after trauma. Following surgery.SP-A,SP-D mRNA deceased and CaN-αmRNA inceased showed that calcineurin,surfactant protein make a role in the pathogenesy of lung injury after trauma.Compared with Group normal,the mitochondria energy metabolism decreased.Following interventions the data shows that PPG,FK-506 may be a protection factor of lung damage after trauma,however,NaHS may increase the lung damage after trauma.Aldactone shows no definite effect.Conclusions:Trauma can induce lung injury.The injury is the most serious in 4-6 hours after trauma.The mechanism may be involved in the activating of neutrophil and inflammatory cytokines,excess oxidative stress,the imbalance of oxidant-antioxidant system,high secreting of aldosterone.The down-regulation of endogenous H₂S/CSE system,down-regulation of SP,up-regulation of CaN-αmay play an important role in lung injury.PPG,FK-506 may protect lung injury after trauma.:Amputation can induce lung injury.The ratio of wet to dry lung tissue weight(W/D)is the largest in 6 hours after operation The down- regulation of endogenous H₂S/CSE system may play an important role in lung injury during operation trauma.