Expression And Role Of TNF-a, IL-6 And Hs-CRP In The Formation Of Pressure Ulcer In Rats After Chemotherapy

Objective:To establish chemotherapy rats of pressure ulcer rat model and simple rat model of pressure ulcer,extracted rat blood and compressed tissue,Enzyme linked immunosorbent assay?Elisa?was used to detect the levels of hs-CRP protein and Western blot?WB?was used to detect the expression of TNF-a and IL-6 protein,to observe the pathological changes by light microscopy,and observe the susceptibility of chemotherapy rats pressure ulcer and explore expression and mechanism of TNF-a,IL-6 and hs-CRP protein in rat model,to study the influencing factors of the occurrence of pressure ulcers,to find sensitive index which can predict the incidence of pressure ulcers in the rats,and to provide reference and direction for the prevention and treatment of pressure sores.Methods:80 healthy SD rats were randomly divided into blank control group?n=10?,experimental control group?n=30?and experimental group?n=40?.The experimental control group used pressure device to act on rat gracilis muscle,giving 34.7kPa pressure,to pressure of 2h and remove of 0.5h to simulate the ischemia-reperfusion process,with 2.5h as a cycle,30 rats corresponding to underwent 2,3,4 I/R?ischemia reperfusion?to establish rat models with different pressure cycle the degree of injury,while the experimental group by 5-FU?5-fluorouracil?intraperitoneal injection,according to the first dose of 125mg-kg^-1,the continuous three days maintenance dose of 62.5mg·kg^-1·d^-1,before treatment,first days after drug,seventh days after drug,weighing and blood routine examination,rats were observed during the external signs of change.After successful establishment of the model of chemotherapy,2,3,4 I/R cycle was used to establish the model of pressure ulcer in rats.The model of pressure ulcer was consistent with that of the control group,while the blank group did not do any treatment.Three groups of rats were extracted blood and compressed tissue after experiment,the blood were added to anticoagulant tube and dry tube,to extract supernatant centrifugal,part of the compression organization mashed after grinding to add protein lysis and centrifugation,adding protein sample buffer,heating 4 min at 100?,stored at-80?refrigerator to prepare fordetected,using Elisa to detect hs-CRP protein content in plasma,WB to detect serum and tissue fluid of TNF-a,IL-6 protein expression,and compression of the skin and tissue sections used for HE staining and pathological section were observed and compared between groups.Results:1 Macroscopic observation and Light microscope observation:After the compression,compared with pressure sores,the chemotherapy group rats'skin range of red dot is more larger.The chemotherapy group rats stratified epithelial structure is generally thin and unclear,some epithelial structure disappeared while severe injury.The structure of skin appendages was less than that of simple pressure ulcer group,dissolution is serious when severe injury,the infiltration of inflammatory cells is more obvious,the fat particles vascular congestion is unfounded,vascular congestion stasis,vascular wall thickening,swelling.In the same 10 magnification view,rat model of pressure ulcer group can only observe the skin or muscle tissue,but the chemotherapy group because of skin thinning,reduced tolerance,in the same field can be observed both skin and muscle tissue,epidermis and dermis,the skin and muscle tissue dissection is obvious,muscle gap widened,more easier to dissolve and breakage.According to the classification standard of skin muscle tissue under the light microscope,the rats were subjected to the damage classification,statistics with mild injury group,moderate injury,severe injury cases and comparison between groups,the difference was statistically significant?X²=62.309,P<0.01?,the experimental group?chemotherapy group?rats total number of cases of severe injury in 13cases,the 3 cases in the control group,the experimental group appeared severe injury cases in rats is much higher than the experimental group.2 In seventh days after the end of chemotherapy,rats body quality?X₁?,red blood cell?X₂?,white blood cell?X₃?,platelet?X₄?count to be set as independent variables,the degree of skin injury grading Y as dependent variable,using multiple stepwise regression to analys factors which affect the degree of injury of rat skin,the model contains white blood cells as independent variable?P<0.05?isfitting,regression fitting model is established,regression equation:Y=4.918-0.298·X₃,the white blood cell count is considered to be the main factors affecting the degree of skin injury.3 At the same pressure?34.7kPa?and the same cycle of ischemia reperfusion?I/R2,I/R3,I/R4?times,compared with simple ulcer group and blank group,the chemotherapy pressure ulcer group rats plasma and tissue fluid hs-CRP protein content higher,comparison between groups?P<0.05?,the difference was statistically significant.4 At the same pressure?34.7kPa?and the same cycle of ischemia reperfusion?I/R2,I/R3,I/R4?times,the chemotherapy pressure ulcer group rats'band of TNF-a is generally higher than that of the blank group and the ischemia reperfusion group,and the expression of the intensity was higher than that of the latter,comparison between groups?P<0.05?,the difference was statistically significant.5 At the same pressure?34.7kPa?and the same cycle of ischemia reperfusion?I/R2,I/R3,I/R4?times,I/R4 group and chemotherapy group+I/R4 in serum of rats with more thicker band of IL-6 than in blank group and the other experimental group,simply I/R group generally higher expression than chemotherapy+I/R group,comparison between groups?P<0.05?,the difference was statistically significant.It was speculated that the decrease secretion of IL-6in the blood of the chemotherapy group caused by the decrease of the white cell and decreased immunity.In the rat tissue fluid,the band of IL-6,chemotherapy+I/R group was significantly higher than that of the pure I/R group and the blank group,the expression was higher,the difference between the groups?P<0.05?,the difference was statistically significant.6 With the degree of skin injury Spearman correlation analysis,rat plasma hs-CRP protein were highly correlated with the degree of skin injury?correlation coefficient:r=0.860,P<0.01?;expression of TNF-a in serum and tissue fluid showed moderate degree of correlation with the degree of skin injury?correlation coefficients:r₁=0.320,P<0.01;r₂=0.657,P<0.01?;expression of IL-6 in serum and tissue fluid of rats was low and moderate correlation with the degree of skin injury?correlation coefficients:r₃=0.294,P<0.01;r₄=0.467,P<0.01?.The changes of TNF-a expression in rat plasma hs-CRP and tissue fluid were significantly correlated with skin injury.Conclusion:1 Compared with the blank group and the simple pressure ulcer group,the skin of rats after chemotherapy was more likely to be damaged,the skin tolerance was reduced and the degree of injury was more serious.In addition to the damage and applied pressure device is related to the interaction,and after ischemia reperfusion in rats induced by stress reaction,inflammatory factor hs-CRP,TNF-a,IL-6 was released jointly participate in the inflammatory reaction,and the expression of TNF-a and content of hs-CRP were non chemotherapy group rats.2 After chemotherapy infusion,when the white blood cell count is less than 30%of normal,the risk of pressure sores will increase.3 The change of hs-CRP protein content in the plasma and the expression of TNF-a in the tissue fluid had predictive effect on the occurrence of pressure ulcers to a certain extent.The higher content or expression of two indicators,the higher risk of pressure ulcer.