The Research on the Protective Effect of Intraperitoneal Injection of Perfluorocarbon for Lung Ischemia Reperfusion Injury in Rats
|School||Luzhou Medical College|
|Keywords||Ischemia-reperfusion injury(IRI) Perfluorocarbon(PFC) Tumornecrosisfactor(TNF) Aquaporin1(AQP1) Epithelial Na+channel(ENaC)|
Background and objectiveIn1966Clarkaccidentally found the mouse had fallen into theperfluorocarbon survived, which ushered in the application of perfluorocarbonin the medicine.PFC (Perfluorocarbon PFC) is a kind of hydrocarbon,colorless, tasteless and insoluble in water and blood.Due to its good ability ofcarrying O2、CO2and its high proportion of properties, PFC expandedcollapsed alveolar, regulates pulmonary ventilation/perfusion ratio, andimproved pulmonary gas exchange and anti-inflammation so that thepulmonary injury would be reduced.At present a large number of experiments in clinic and on animal showthat PFC gets a good effect on acute lung injury (ALI), acute respiratorydistress syndrome (ARDS) and so on, but there are few research reportsabout the protective effect of PFC on lung ischemia reperfusioninjury.Therefore, through establishing a improved model of a rat getting lungischemia-reperfusion injury (LIRI), this experiment carried out an initialresearch about the preventive effect of preventive intraperitoneal injection ofPFC（C8F18） on lung ischemia reperfusion injury.MethodA model of ratus pulmonary ischemia-reperfusion injury was established in some standard (SD) rats, weight from180g to250g, all ratswere randomly devided into3groups: blank group, contrast group, test group.blank group was treated with open and close chest without lung I/R treat;control group was treated with lung I/R followed0.9%NS (15ml/Kg)intraperitneal injection48h before; test growp was treated with lung I/Rfollowed C8F18(15ml/Kg) intraperitneal injection48h before the operation.On the day of the operation the rats underwent anesthesia by takingintraperitoneal injection of2%pentobarbital (40mg/kg), and then fixed,made a freedom of their right femoral artery, femoral vein and a creation ofvascular access. Endotracheal intubation was connected by animal ventilatorthrough tracheotomy, and0.5ml blood which came from I/R group via thefemoral vein catheter was used for the detection of C8F18concentration inwhole blood. Then,after left hilum’s being revealed by the3-5intercostalthoracotomy on the left side, left hilar45min was closed by the noninvasivevascular clipping, and the rats were sacrificed in2h,4h,6h after the recovery ofleft pulmonary circulation by the loosening of the noninvasive vascularclamp.Through reperfusion at2h,4h,6h the result can be taken by theexpression of the blood from the femoral artery and femoral vein,the lungtissue morphology of I/R group and NC group and NS group from thedetection of the left lung tissue, the wet to dry weight ratio of lung, pathology,the tumor necrosis factor (TNF alpha) in pulmonary tissue, Aquaporin1 (AQP1) and Epithelial Na+channel (ENaC), and the analysis on arterialblood.Results1. The morphological changes of lung tissue: the lung tissue of NC group at2h,4h,6h was ruddy and elastic, and had no petechiae and no swelling, sothere was no obvious difference between the three groups. The lung of groupNS at2h,4h,6h had a little petechiae and local tissue swelling and was lesselastic,which at2h was the most obvious. The lung tissue of I/R group at2h,4h,6h had a little petechiae,and its texture and elasticity decreased which at2h and4h was more obvious than that at6h.Therefore, compared with the NSgroup, I/R group at each time point were better.2. The wet/dry weight ratio (W/D)of lung: when a rat had pulmonaryischemia reperfusion injury (NS group), compared to control group (NC),itsW/D ratio of lung tissue increased (P <0.05).In addition,its W/D of the lungtissue of I/R group was clearly higher than that of NC group(P <0.01) whilethat of I/R group and NS group had no significant difference (P>0.05).3. Blood gas analysis: compared with group NC, the Pa02value of NS at2h,4h,6h had a big decrease (P <0.05),and compared with group I/R, NSgroup at each time point were significantly different (P <0.05) while NCgroup and I/R group at each time pointe had no significant differences (P>0.05). Compared with group NC, the PaCO2of NS at each time point had a bigincrease (P <0.05),and compared with group I/R, NS group at2h wassignificantly different (P <0.05) while it at4h,6h had no big differences (P>0.05). The PH at each time point of the three groups had few differences.4.Tumor necrosis factor TNF-α: TNF-a concentration in the serum of I/Rgroup and NS group was obviously higher than that in NC group (P <0.05).Compared with group NS, TNF-α concentration in I/R group at2h had a bigdecrease (P <0.05) while at4h and6h there was no significant difference (P>0.05).5.Pathological section (HE): The lung tissue structure of the rats of groupNC was clear and its alveolar is complete with no changes such ascongestion, edema, inflammatory exudation, and so son. in the lung tissue ofthe NS group at each time point the Infiltration of inflammatory cells, thecollapse or atelectasis of part of the alveolar and local red cell exudation wereseen, in which the2h was most obvious. Compared with NS group at eachtime point, the I/R group finds inflammatory cell infiltration, and alveolaratrophy and atelectasis in the lung tissue of rats. However, comparing the twogroups at each time point shows a significant decrease in pathologicalmorphological changes in I/R group(P <0.05).6.Immunohistochemical: The expression of AQP1protein was the mostobvious in group NC. AQP1staining of group NS significantly reduced ingroup2h, which decreased significantly (P <0.05) compared to NC group at each time point, when AQP1protein of I/R group increased significantly(P <0.05) compared to that of NS group. The expression of ENaC proteinwas the most obvious in group NC., ENaC staining in group NS significantlyreduced, which decreased significantly (P <0.05) compared to that in NCgroup at each time point, while ENaC protein in I/R group and NS group hadno big difference (P>0.05).Conclusion1Through establishing a improved model of a rat getting lung ischemia-reperfusion injury (LIRI)，to make the operation more convenient, lessconfounding factors;2Peritoneal injection of C8F18can reduce the liquid exudation in thealveoli, alveolar collapse, and decline the lung pathological damage of LIRI.3Peritoneal injection of C8F18can effectively improve Pa02decline causedby the lung ischemia reperfusion injury in rats, promote pulmonary gasexchange, decrease alveolar fluid exudation and reduce pulmonarypathological damage.4Peritoneal injection of C8F18inhibited to some extend in a rat lungischemia-reperfusion injury for the release of cytokine in lung tissue such asTNF-a.5Peritoneal injection of C8F18can effectively reduce the rats’ reaction topulmonary edema and inflammatory and increase AQP1, ENaC proteinexpression.