Expression Of MIF And ICAM-1 In Severe Acute Pancreatitis Associated Lung Injury In Rat

Objective To establish an severe acute pancreatitis animal model and study the role of the macrophage migration inhibitory factor (MIF) and intercellular adhesion molecule 1 (ICAM-1) at severe acute pancreatitis associated lung injury (SAPALI) in rat.Methods 60 specific pathogen free (SPF) wistar male rats were divided into five groups randomly: blank group (n=12), sham-operated group (n=12), six hours after SAP group (n=12), twelve hours after SAP group (n=12), twenty-four hours after SAP group (n=12). SAP was induced by injection of 5% Na-Tc under membrane of pancreas. The rats were killed at sixth hour after operated in Sham-operated group. The rats were killed at sixth, twelfth and twenty-fourth hour after Na-Tc injection in six hours after SAP group, twelve hours after SAP group and twenty-four hours after SAP group respectively. The content of amylase in serum was measured by holo-automatic biochemical analysator. Pancreatic and pulmonary tissues were observed by hematoxylin-eosin (HE) staining, and were counted for the pancreatic tissues and histological scores and pulmonary histopathologic scores. Appling Blood-gas Analyzer determination PO2 and PCO2.Detecting the concentration of soluble intercellular adhesion molecules-1 (sICAM-1) in serum with ELISA method. Detecting the expression of intercellular adhesion molecules-1 (ICAM-1) and macrophage migration inhibitory factor(MIF)in pancreatic tissue and pulmonary tissue by immuno- histochemical method. Detecting the pulmonary Myeloperoxidase (MPO) activety. All the data were analyzed by statistics software SPSS18.0. Normal distribution measurement data was shown as means±standard deviation ( x±s). One-way ANOVA method was applied to comparison among groups. And using S-N-K method for binary comparison. Pearson correlation analysis was applied to measure the relevant relations. The inspection standards was alpha = 0.05.Results We successfully established severe acute pancreatitis animal model. The rats of SAP group exhibited a high amylase, severe pancreatic pathological damage and pulmonary pathological damage after modeling. The index of MIF and ICAM-1 in Sham-operated group compared with Blank group was no significant difference (P>0.05). The index of MIF and ICAM-1 in six hours after SAP group, twelve hours after SAP group and twenty-four hours after SAP group compared with blank group and sham-operated group was significant difference(P<0.01), and six hours after SAP group, twelve hours after SAP group and twenty-four hours after SAP group compared with each other was significant difference(P<0.05). The content of MPO activity and sICAM-1 in sham-operated group compared with blank group was no significant difference (P>0.05). The content of MPO activity and sICAM-1 in six hours after SAP group, twelve hours after SAP group and twenty-four hours after SAP group compared with blank group and sham-operated group was significant difference (P<0.05), and six hours after pancreatitis group, twelve hours after pancreatitis group and twenty-four hours after pancreatitis group compared with each other was significant difference(P<0.05). Pancreatic histopathologic scores and pulmonary histopathologic scores were highly relevant existing (r>0.7).The content of sICAM-1, MIF,ICAM-1 and MPO horizontal were highly related (r>0.7) with the content of pulmonary histopathologic scores.Conclusions①In the severe acute pancreatitis associated lung injury, the lung injured degree is closely related to the degree of the pancreatic injury.②In the severe acute pancreatitis associated lung injury, the expression of MIF is positively correlated with the lung injured degree.③In the severe acute pancreatitis associated lung injury, the expression of ICAM-1 is positively correlated with the lung injured degree.