Role Of HO-1/Coon Post-Shock Mesenteric LYMPH Drainage Alleviating Acute Lung Injury Following Hemorrhagic Shock

The preliminary study found that the ligation of intestinal lymphatic can mitigate lung injury in hemorrhagic shock and the two-hit rats, intestinal lymph drainage in resuscitation rat can mitigate lung injury caused by hemorrhagic shock; it shows that intestinal lymph reflux is an important factor in shock-mediated acute lung injury and its mechanism except intestinal lymph carries a variety of toxic substances back to the body, other mechanisms need to study.The process of acute lung injury caused by shock, a variety of antioxidant enzymes play an important role in lung protection. Heme oxygenase-1(HO-1) is a starting enzyme and rate-limiting enzyme which degradated heme for carbon monoxide (CO), iron and bilirubin, in recent years,it has anti-inflammatory, anti-apoptotic anti-oxidation function. And CO as a novel gaseous signal molecule, related with lung injury. But what is the function of HO-1/CO system in the pathogenesis process in intestinal lymph-mediated acute lung injury rats. Shock intestinal lymph as a target for prevention and treatment of shock has a positive meaning.Therefore, the study observe that the intestinal lymph drainage impact on HO-1/CO in lung tissue, Use Tool drugs which affect HO-1/CO System is zinc protoporphyrin (ZnPP) and hemin (HM), explore mechanisms that intestinal lymph drainage to reduce lung injury in rats, and clarify HO-1/CO mechanisms in intestinal lymph-mediated lung injury.30healthy male Wistar rats were randomly divided into:sham group, shock group, shock+drainage group, shock+drainage+ZNPP group, and shock+drainage+ZnPP+HM group. Hemorrhagic shock model was replicated by the conventional method of my laboratory, after maintain low blood pressure1h, fluid resuscitation (30min) through the femoral vein, and observed for3h:shock group only replicate the model, parallel fluid resuscitation;shock+drainage group after hypotension1h,intestinal lymph drainage and fluid resuscitation, other steps are the same as the shock group; shock+drainage+ZnPP group conduct intraperitoneal inject the experiment ZnPP (10mg/kg) before12h, other steps are the same as the shock+drainage group; shock+drainage+ZnPP+HM group, entered HM (10mg/kg) via the femoral vein at the same time with fluid resuscitation, other steps are the same as the shock+drainage+ZnPP group; sham group implement the same surgical procedures and no phlebotomy, no infusion. All animals of the experiment, the other side of the femoral artery connected to the bio-signal acquisition system to monitor the mean arterial blood pressure (MAP).3h (sham group at the corresponding time points) at the end of the shock and liquid resuscitation, all animals, blood in abdominal aorta, preparation of plasma to detect total protein; thoracotomy and take the lung tissue, lung left lobe conduct bronchial lavage, get specimens of bronchoalveolar lavage fluid (BALF), cells count, supernatant after BALF centrifugation to detect the protein content and calculation lung permeability index (LPI=total protein of BALF/plasma total protein): specimens from the right upper lobe, detect wet and dry ratio (D/W); specimens from the right middle lobe and vice leaves, frozen at-80℃, the preparation of tissue homogenates, detect HO-lactivity and CO content, the content of the tumor necrosis factor (TNF-a), specimens from the right lower lobe, the routine preparation of tissue sections to observe the histological changes.The results showed that:1. The changes of cell contents in BALF: shock group, shock+drainage group, shock+drainage+ZnPP group, shock+drainage+ZnPP+HM group, total cells numbers was significantly higher than the sham group; cells numbers in shock+drainage group was significantly lower than that in the shock group, shock +drainage+ZnPP group and shock+drainage+ZnPP+HM group was significantly higher than that in shock group,shock+drainage group, shock+drainage+ZnPP and shock+drainage+ZnPP+HM group, between the two groups,it is no statistically differences.2.The change of D/W of lung tissue:in shock group,shock+drainage+ZnPP group,shock+drainage+ZnPP+HM group,D/W of lung tissue was significantIy lower than that in the sham group；shock+drainage group was significantly higher than that in shock group,and no significant diffe:rence with the sham group；shock+drainage+ZnPP group,shock+drainage+ZnPP+HM group was significantly lower than that in the shock+drainage group; shock+drainage+ZnPP group,shock+drainage+ZnPP+HM group were no difierences.3.LPI change:shock group,shock+drainage+ZnPP group,shock+drainage+ZnPP+HM group were significantly higher that that in sham group；LPI in shock+drainage+ZnPP group,shock+drainage+ZnPP+HM group was significantly h igher in the shock group and shock+drainage group.4.Morphological changes:the structural integrity of the lung tissue in sham group,evenly spaced alveolar was no capillary congestion phenomena,alveolar spaces is clear,no cellulose exudation,no neutrophil exudation；shock group,we can see the intelwal of visible lung congestion,edema,rupture,alveolar space and the interval innammatory cell infiltration,nocculent fibrous protein materialin alveolar, focal atelectasis;in shock+drainage group,histological damage was slighter than that in shock group；in shock+drainage+ZnPP group,lung damage was more serious than that in shock+drainage group,we can see lung interval edema,part alveolar1oss normal structure；compared with the shock+drainage+ZnPP group,in shock+drainage+ZnPP+HM group,the lesion was mitigation.5.HO-1activity change in lung tissue:in shock group. shock+drainage group.hock+drainage+ZnPP+HM group,Ho.1activit),of lung tissue was signmcantly higher than that in sham group；in shock+drainage group,HO-1activity of lung tissue was significantly lower than that in shock group.6. CO content in lung tissue: shock group, shock+drainage group,shock+drainage+ZnPP+HM group, COcontent was significantly higher than that in sham group,;in shock+drainage+ZnPP group, CO content was significantly lower than that in shock group and shock+drainage group; CO content in shock+drainage+ZnPP+HM group was significantly lower than that in shock group.7. TNF-a content in lung tissue:in shock group、shock+drainage group、 shock+drainage+ZnPP group、shock+drainage+ZnPP+HM group, TNF-a content was significantly higher than that in sham group;in shock+drainage group, TNF-a content was significantly lower than that in shock group;in shock+drainage+ZnPP group, TNF-a content was significantly higher than that in shock+drainage group.Those results suggest that intestinal lymph drainage can mitigation lung injury in hemorrhagic shock rats, HO-1/CO plays a certain role in the pathogenesis process of acute lung injury in intestinal lymph-mediated shock rats, its mechanism is related with regular inflammation of lung tissue. The results provide an experimental basis for the prevention and treatment of acute lung injury after shock.