Ulinastatin ameliate lung damage induced by mechanical ventialtion for serious burned rats:an experimental study

Objective To explore the potential protective effects of ulinastatin on ventilation-induced lung injuries of severe burned rats.Methods Ninety Wistar rats were randomly divided into three experimental groups:control group(n=30),ventilation group(n=30)and ventilation-ulinastatin group(n=30).After establishing the severe burn model,the rats of latter two groups were mechanically ventilated for 1 hour with or without the pre-treatment of ulinastatin.The lung injury was evaluated by pathological changes,lung index and the expression level of cytokines including TNF-α,IL-2,and IFN-γ at 2 hours,6 hours and 12 hours post-ventilation.The samples of lung tissue at the last time point(12 hours)were used for both HE staining and electron microscopy analysis.Results The lung tissues of the control and ventilation groups exhibited markedly pulmonary edema and scattered hemorrhagic foci.In contrast,ventilation-ulinastatin group demonstrated milder pulmonary edema.HE staining revealed that the pathological changes of ventilation-ulinastatin group were milder than ventilation group.Under electron microscopy,severe organelle destruction was noted for the lung tissue of control group and ventilation group.In contrast,ventilation-ulinastatin group demonstrated milder pathological changes.Pulmanary index showed that the value of ventilation-ulinastatin group decreased significantly compared with ventilation group.Immunohistochemical staining demonstrated lower expression of TNF-α,IL-2,IFN-γ in ventilation-ulinastatin group compared with ventilation group.Conclusions Ulinastatin attenuated ventilation-induced lung injury in a severe burn model of rat.The protective effects of ulinastatin maybe related to the capacity of ulinastatin to reduce the expression of cytokines including TNF-α,IL-2,and IFN-γ.