The Protective Effect Of Necrostatin-1on The Lung After Trauma-hemorrhagic Shock

Objective:In this experiment, SD rats were established nonfatal traumatic hemorrhagic shock model for the study, and then pathological changes in the lung tissue, protein content in branches alveolar lavage fluid, receptor interaction protein1(RIP1) and RIP3, the proportion of necroptosis cells are observed in different groups. And observe the influence of Nec-1to the indicators above, and verify the protective effect on lung injury that T/HS induce. Then we discussed the possible mechanisms, in order to provide theory evidence for mechanisms of MODS.Method:A total of96male adult SD rats were divided into the following groups: trauma sham-shock (T/SS), trauma-hemorrhagic shock (T/HS), intervention, vehicle control groups, every group includes3point in time-2,6,12hour. T/HS group were suffered from trauma-shock and resuscitated, intervention group received Nec-1(lmg/kg, iv)5mins before resuscitation, and the same volume of the vehicle only for vehicle control group at the same time. At2,6,12hour, the lung were obtained for pathological examination, the content of pertain in bronchoalveolar lavage fluid (BALF) by Pierce BCA protein assay kit, the content of RIP1and RIP3by western blot, and necroptic cells by flow cytometry.Results:1. HE staining and Microscopic examination:at all the time point, the lung has little differences in T/SS rats, and the point of pathology score has no statistical difference(p>0.05). Compared with T/SS rats, the lung of T/HS rats has severer lung injury and high point in pathology score (p<0.01) at each time point. At every time point, there is little difference between vehicle control groups and T/HS groups, and the point of pathology score has no statistical difference(p>0.05). In the rats of intervention group, at every time point, pathological changes is obvious-lighter than T/HS rats and severer than T/SS rats, there are the same change in pathology score (Intervention p<0.01vs. T/HS, Intervention p<0.01vs. T/SS).2. Protein content in BALF:At all the time point, Protein content has little differences in T/SS rats(p>0.05). In T/HS rats, protein content in BALF is gradually increased with time going (p<0.01), and at every time point, protein content in T/HS rats BALF are more than T/SS rats (T/HS p<0.01vs. T/SS (2,6,12hours)). At every time point, there is little difference between vehicle control groups and T/HS groups in protein content in rats BALF (p>0.05). At the time point of2hours and6hours after the beginning of resuscitation, protein content in intervention group rats’BALF has no difference with T/HS rats’(p>0.05), but we can get the different outcome at the time point of12hours after the beginning of resuscitation (p<0.05). But at each time point after the beginning of resuscitation, protein content in intervention group rats’ BALF is more than at the T/SS group.3. The expression of RIP1and RIP3:At all the time point, the expression of RIP1and RIP3are similar in T/SS rats (p>0.05). In T/HS rats, the expression of RIP1and RIP3is gradually increased with time going (T/HS (6hours)p<0.01vs T/HS2hours and T/HS12hours), and compared with T/SS rats, the lung of T/HS rats express more RIP1and RIP3(T/HS vs. T/SS (2,6,12hours),p<0.01). At every time point, there is little difference between vehicle control groups and T/HS groups in the expression of RIP1and RIP3(p>0.05). At the time point of6hours and12hours after the beginning of resuscitation, the expression of RIP1and RIP3is less than T/HS group (p<0.05), and more than T/SS group (p<0.01).4. The proportion of necroptic cells:Compared with T/SS rats, at every time point, T/HS rats have more necroptic cells (p<0.01), and the number is increased with time going (p<0.01). In T/SS group rats, the proportion of necroptic cells has no difference between each time point (p>0.05). At every time point, there is little difference between vehicle control groups and T/HS groups in the proportion of necroptic cells (p>0.05). Compared with T/HS rats, the proportion of necroptic cells in intervention group is smaller at all the time points (p<0.01). Compared with T/SS rats, the proportion of necroptic cells in intervention group has no difference at the time point of2hours after the beginning of resuscitation (p>0.05), and has obvious difference at6hours (p<0.05) and12hours (p<0.05).Conclusion:1. Traumatic hemorrhagic shock can lead to lung injury in rats increased capillary permeability, hyperemia, hemorrhage, micro-thrombosis, pulmonary alveolar protein-rich fluid in the interstitial exudation and inflammatory cell infiltration, and over time within12h extend gradually increasing trend. The Nec-1could partially inhibited this phenomenon. 2.There are necroptic cells in the lung injury induced by T/HS, and gradually increased with time going in12hours after the beginning of resuscitation.Nec-1could inhibit partially the occurrence of necroptic cells in the lung injury induced by T/HS, and persists in12hours after the beginning of resuscitation.3. Nec-1could inhibit partially the occurrence of necroptic cells in the lung injury induced by T/HS in12hours after the beginning of resuscitation, and the inhibition should be argued and more experiments should be taked.